Tesi: "Aroma" – Grafiati

1

Kant, Avinash. "Starch-aroma interactions." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403302.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

2

Гладченко, Оксана Робертівна, Оксана Робертовна Гладченко, Oksana Robertivna Hladchenko, and A. Shymarina. "Why aroma marketing?" Thesis, Вид-во СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/17143.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

3

Haines, David Sean. "Osmologies : towards aroma composition." Phd thesis, Sydney College of the Arts, 2012. http://hdl.handle.net/2123/14423.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

4

Bernath, Konrad. "Das Böckser-Aroma in Wein /." Zürich, 1997. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=12079.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

5

Persson, Gabriel, Henrik Haegermark, and Markus Kvarnvik. "Aroma Theory: Scenting the Attitude." Thesis, Linnéuniversitetet, Ekonomihögskolan, ELNU, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-10547.

Testo completo

Abstract (sommario):

The thesis examines the relationship between consumer attitudes and a scented shopping environment. A relationship and phenomena concerning scent marketing, which could be seen as one of the more provocative forms of marketing since the human sense of smell, is connected to the limbic system where motivation and attitudes are created. The use of scent marketing has, so far, been proven effective in sales increasing whereas it is one of the less explored forms of marketing. The purpose of the thesis is to answer the following question: Is it possible to find differences in consumer attitudes in a scented buying environment compared to a nonscented buying environment, and thereby create new basis for segmentation? The thesis is based on a quantitative study where data has been gathered in a scent manipulated buying environment through structured interviews with consumers. The thesis applies a deductive approach to the main theories in the area of interest. The findings suggest new theory discussing that it is difficult to use consumer attitudes, towards a scented store environment, as a foundation for market segmentation. Further the results of the executed scent experiment comply with the existing theories about the affect of scent marketing as a sales increasing marketing tool.

Gli stili APA, Harvard, Vancouver, ISO e altri

6

Lam, Siu-ping, and 林少萍. "Aroma profiles of soy sauces." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31221105.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

7

Lam, Siu-ping. "Aroma profiles of soy sauces /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21185591.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

8

Robinson, Anthony. "Environmental influences on grape aroma potential." Thesis, Robinson, Anthony (2011) Environmental influences on grape aroma potential. PhD thesis, Murdoch University, 2011. https://researchrepository.murdoch.edu.au/id/eprint/5832/.

Testo completo

Abstract (sommario):

Understanding the source of wine volatile compounds and the mechanisms that influence their formation through grape growing, winemaking and storage is essential for wine businesses when developing strategies to produce wines with specific sensory attributes that appeal to target markets. The objective of this research was to develop a greater understanding of the environmental influences that drive flavour formation in grapes and translate this information into awareness of the limitations of site and region in producing wines to specification. A novel analytical method was developed utilising headspace solid-phase microextraction (HS-SPME) for the analysis of wine volatiles by comprehensive two-dimensional gas chromatography (GC × GC) time-of-flight mass spectrometry (TOFMS). The analytical technique was able to resolve and identify a substantially larger number of volatile compounds than current single dimensional GC-MS methodologies. While developing this method it became clear that there was a need to develop a greater understanding of wine matrix effects on SPME-based analyses of volatile compounds found in grape juices and wines of which ethanol and glucose had the greatest effect. Furthermore, the impact of shipping conditions in relation to wine composition and sensory characteristics was investigated to ensure sample integrity across the experiments. The HS-SPME GC × GC-TOFMS methodology was applied in conjunction with descriptive sensory analysis to field studies exploring the effects of site, viticultural management, and winemaking on wine composition and sensory characteristics. This study identified that site was a major influence on Cabernet Sauvignon wine composition and sensory characteristics leading to an extensive study exploring the composition and sensory attributes of a number of commercially produced Cabernet Sauvignon wines from ten wine growing regions of Australia. The results of the studies have enabled the integration of sensory and chemical data Australian Cabernet Sauvignon wines which has revealed potential chemical markers of sensory attributes and compositional characters that are associated with Australian wine regions.

Gli stili APA, Harvard, Vancouver, ISO e altri

9

Spillman, Philip John. "Oak wood contribution to wine aroma /." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09AHP/09ahps756.pdf.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

10

Albano, Neide Munhoz. "A essência dos aromas e o aroma das essências : por um protótipo de glossário terminológico da aromaterapia." Universidade Estadual de Londrina. Centro de Letras e Ciências Humanas. Programa de Pós-Graduação em Estudos da Linguagem, 2010. http://www.bibliotecadigital.uel.br/document/?code=vtls000161004.

Testo completo

Abstract (sommario):

O suporte teórico deste trabalho tem como base a compreensão de novas possibilidades da Terminologia, a partir das perspectivas propostas por Cabré (1999), delineando-a como campo interdisciplinar em que os termos, até então assim denominados, nada mais seriam que itens lexicais ativados em contextos específicos pela língua posta em funcionamento, a Teoria Comunicativa da Terminologia, ou simplesmente a TCT. Desta forma, a possibilidade da variação terminológica, plenamente aceita pela TCT, distanciando-se dos estudos teóricos tradicionais que propunham a descrição e análise do léxico de uma dada ciência ou técnica, sistematizando-o a fim de extinguir qualquer possibilidade de ambigüidade nas linguagens técnicas, tornou possível a descrição e a análise dos usos dos termos variantes no contexto especializado da Aromaterapia. O objetivo principal desta pesquisa configura-se na compilação, descrição, análise e elaboração de um protótipo de glossário terminológico, o GLOTEAR (Glossário Terminológico da Aromaterapia). A pesquisa resultou no registro de 245 (duzentos e quarenta e cinco) termos relacionados ao campo conceptual da Aromaterapia: óleos essenciais, óleos vegetais carreadores e técnicas de extração. A análise dos termos variantes privilegiou os neologismos semânticos (tratados como casos de terminologização e metaterminologização), os neologismos alogenéticos (estrangeirismos e decalques), as variantes formais, informais e ortográficas. O trabalho demonstrou que a variação terminológica no âmbito abordado contribui substancialmente para o enriquecimento do léxico geral da língua portuguesa. The Communicative Theory of Terminology with its new possibilities proposed by Cabré since 1999, as an interdisciplinary field when terms starteded to be seen as lexical items activated in specific contents by a certain language, is the main foundation for this research. Therefore, the possibility of terminological variation, fully accepted by TCT, leaving behind the traditional theorists and their beliefs on the description and analysis of the lexicon of a given science or a technical field, as well as the systematisation of terms, in order to extinguish the possibilities of ambiguity within technical languages, brought the possibility of description and analysis of the variation in the Aromatherapy area. This way, the main objective of this research is to develop a word list, store them and create a glossary, the so called Aromatherapy Terminological Glossary. The research made possible to register 245 terms realted to the Aromatherapy field: essential oils, carrier vegetable oils and oil extraction techniques. Special attention was given to semantic neologisms (terminologisation and metaterminologisation), alogenetic neologisms (foreing words), formal and informal variation, and also orthographic variation. The research has shown that the variation in the Aromatherapy area has contributed to enrichen the Portuguese Language Lexicon.

Gli stili APA, Harvard, Vancouver, ISO e altri

11

Isci, Asli. "Recovery Of Strawberry Aroma Compounds By Pervaporation." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605084/index.pdf.

Testo completo

Abstract (sommario):

Pervaporation is a selective membrane technique in which a liquid feed mixture is separated by means of partial vaporization through a non-porous perm-selective membrane. This method can be used for the recovery of heat sensitive aroma compounds to avoid them from thermal damage in beverage industries. The main objective of this study was to determine the effects of feed temperature (30, 40, 50&deg C), composition (different model solutions, strawberry essence), concentration (50, 100, 150 ppm) and permeate pressure (4, 8 mbar) on the recovery of aroma compounds of strawberry by pervaporation in terms of mass flux and selectivity. In addition, it was aimed to optimize the extraction conditions (extraction time, temperature, agitation speed, strawberry matrix) of Solid-phase microextraction (SPME), which is used for the analysis of strawberry aroma compounds. Optimum results for SPME were obtained at 40&deg C, 700 rpm for 30 min and no matrix effect was observed. Pervaporation experiments were performed using a hydrophobic membrane, PERVAP 1070 (PDMS). As the feed temperature increased, the mass flux and selectivity increased and the total mass flux followed an Arrhenius type relation. Decreasing downstream pressure increased both total flux and selectivity, while increase in feed concentration led to higher organic fluxes but lower selectivities. In general, PERVAP 1070 showed a higher selectivity towards Methyl butyrate (MTB) than Ethyl butyrate (ETB) and MTB flux was affected negatively by the presence of ETB in the feed solution. Pervaporation experiments were also performed with a strawberry essence and strawberry model solution. The selectivities of MTB and ETB were negatively affected by the presence of other aroma compounds.

Gli stili APA, Harvard, Vancouver, ISO e altri

12

Ilc, Tina. "Role of cytochromes P450 in wine aroma." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAJ083/document.

Testo completo

Abstract (sommario):

L’annotation détaillée de la superfamille des cytochromes P450 dans le génome de la vigne nous a permis d’étudier sa structure génétique, sa phylogénie et son expression, mais aussi d’identifier des gènes dont l’expression est activée dans le grain à maturité, lors de la synthèse de nombreux composés aromatiques. La lactone du vin est la molécule dont le seuil de détection olfactive est le plus bas, ce qui en fait un composant essentiel de l’arôme du vin. Nous avons pu démontrer que cette lactone se forme au cours du vieillissement du vin par une réaction lente et non-enzymatique à partir du 8-carboxylinalool. L’accumulation de ce dernier dans la baie est concomitante à l’expression de plusieurs P450s, dont CYP76F14 est le plus fortement exprimé. Trois enzymes catalysent des étapes d’oxydation conduisant du linalool au (E)-8-carboxylinalool, mais seul CYP76F14 catalyse efficacement la formation de l’acide. Tant par son activité catalytique que son profil d’expression, CYP76F14 apparaît donc comme le responsable le plus probable de la formation du précurseur de la lactone du vin A thorough annotation of the P450 superfamily in grapevine, revealed its genomic organization, phylogeny and expression. Specifically, we identified genes showing an activated expression in the ripe grape berry, the stage during which the biosynthesis of many aroma compounds takes place. Among the known oxygenated monoterpenols in grapevine, wine lactone has the lowest odor detection threshold and therefore the largest potential impact on wine aroma. We demonstrated that wine lactone is formed during wine ageing via a slow non-enzymatic reaction from the precursor (E)-8-carboxylinalool. We showed that the accumulation of this precursor in grape berries parallels the expression of several cytochrome P450 genes, among which CYP76F14 has the highest expression. While three of them catalyzed some of the oxidative steps from linalool to (E)-8-carboxylinalool, only CYP76F14 efficiently catalyzed the whole pathway. Taken together, CYP76F14 catalytic activity and expression pattern indicate that it is a prime candidate for the formation of the wine lactone precursor in grape berries

Gli stili APA, Harvard, Vancouver, ISO e altri

13

Hollowood, Tracey Ann. "Taste-aroma-matrix interactions determine flavour perception." Thesis, University of Nottingham, 2002. http://eprints.nottingham.ac.uk/10262/.

Testo completo

Abstract (sommario):

A newly recruited sensory panel was trained in magnitude estimation and time intensity sensory techniques. Sensory analysis was combined with instrumental analysis using MS Nose to investigate the relationship between stimulus and perception using simple model food systems. Volatile release data was collected after swallowing aqueous solutions containing a cocktail of aroma compounds. The compounds varied in their persistence during subsequent exhalations dependent on the degree of association with the mucous lining of the throat. The rate of breathing had no effect on the shape or intensity of the release profile. The data was successfully modelled using the basic principles of interfacial mass transfer. The mechanistic model included some estimated parameters for un-measurable anatomical and physiological variables, kinetic properties of the flavour compound and terms to represent the oscillatory breathing and airflow rate. Aside from the 1st exhalation, the model fitted the data very well. The panel rated the intensity of minty flavor in a 6% gelatine gel, containing varying concentrations of carvone. The flavor was assessed using Magnitude Estimation and Time Intensity Methods. In addition, the quantity of carvone released from the gel and reaching the assessors nose was measured, breath by breath during eating, using the MS Nose. The results showed that the quantity of volatile delivered to the nose was directly proportional to the concentration in the sample, however, the absolute quantity varied greatly between individuals. Further differences were observed in the temporal dimension of their release profiles, which related to differences in their anatomy, physiology and eating habits. In some cases, these differences were mirrored by the sensory data. The relationship between perceived intensity and sample concentration was linear for both types of sensory data. Neither the speed of eating nor the concentration of volatile reached in-nose, affected an individuals ability to judge intensity. There was evidence to suggest, however, that the speed of eating affected the level of adaptation to the carvone stimulus. The affinity of the aroma compound for water (hydrophobicity) was an important factor in influencing the temporal characteristics of the instrumental and sensory data. When aroma release was rapid (< Tmax) the sensory response occurred slightly later whereas when the aroma release was much slower (>Tmax), with intensity increasing more gradually, the sensory response preceded the instrumental data. These phenomena were explained in terms of a lag phase for neural processing when the stimulus was presented quickly and adaptation to the stimulus when it was delivered over a longer period of time. A trained sensory panel assessed flavour and sweetness intensity in solutions containing varying concentrations of Hydroxy Propyl Methylcellulose (HPMC), sugar and flavour volatile. The flavour and sweetness of the viscous solutions were rated using magnitude estimation with a controlled modulus. In addition, the concentration of volatile released on the breath was measured using MS Nose. For low concentrations of HPMC (<0.5g/100g), perceived flavour intensity remained the same, however, a steady decrease was noted at higher concentrations (>0.6g/100g). The change in perceived intensity occurred at the point of random coil overlap (c*) for this hydrocolloid. The perceived sweetness of the solution showed a similar pattern with increasing HPMC concentration, although the inflection at c* was not so obvious. Despite the change in perceived flavour intensity, the actual concentration of volatile measured on the breath was not affected by the change in HPMC concentration. Low order polynomial models were produced to describe perceived flavour intensity and sweetness in viscous solutions containing HPMC and potential explanations for the changes in perception were discussed.

Gli stili APA, Harvard, Vancouver, ISO e altri

14

Al-Kateb, Huda M. "Aroma characteristics of some lemon-flavoured herbs." Thesis, University of Reading, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421604.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

15

Marriott, Raymond. "The phytochemistry of blackcurrant flavour and aroma." Thesis, University of Bath, 1986. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760553.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

16

Costa, Argentina Sampaio. "Taxonomia polifasica de Neurospora produtoras de aroma." [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255730.

Testo completo

Abstract (sommario):

Orientador: Vanderlei Perez Canhos Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-07-26T05:43:40Z (GMT). No. of bitstreams: 1 Costa_ArgentinaSampaio_D.pdf: 3583472 bytes, checksum: 141d7e7d0a97209e763b1d63b2769a7b (MD5) Previous issue date: 1999 Resumo: Foi efetuado um estudo taxonômico de vinte e duas linhagens de Neurospora isoladas de beiju de mandioca e vegetação queimada nos Estados do Maranhão e São Paulo. As linhagens estudadas foram caracterizadas quanto à sua morfologia, perfil de proteínas totais, polimorfismos e fragmentos do rDNA 188,288, região espaçadora 188288 e do gene histona H3-1, e produção de aroma. Foram incluídas neste estudo 7 linhagens de referência de 4 espécies de Neurospora: N crassa NRRL 2223, CCT 2680 (=ATCC 24698); N. sitophila ATCC 46892 (produtora de aroma), NRRL 2884 (=ATCC 36935, =CCT 0045); N. intermedia NRRL 5506 (N. sitophila ATCC 56753) e N. tetrasperma NRRL 2164. Os resultados obtidos na análise das características morfológicas sugerem que os isolados pertencem a 7 espécies diferentes. As linhagens obtidas do Maranhão foram identificadas como N. sitophila, com exceção de AC9, identificada como N crassa, enquanto que os isolados do Estado de 8ão Paulo apresentaram uma maior diversidade de espécies: N. sitophila, N. crassa, N tetrasperma, N. dodgei, N. galapogensis, N. africana e N. lineolata. As análises dos perfis de proteínas totais corroboraram os resultados da análise morfológica. Os resultados da análise de proteínas totais, assim como os de digestão da região espaçadora 188-288 com a endonuclease Ava II, permitiram agrupar a linhagem N. sitophila ATCC 46892 produtora de aroma e isolados obtidos do mesmo susbstrato (beiju de mandioca) e local (Maranhão). Estas linhagens formaram um grupo distinto das linhagens de referência e dos demais isolados. A digestão do rDNA 18S com a enzima de restrição Hae III resultou em padrões diferentes para as três linhagens de referência em estudo. A linhagem produtora de aroma N sitophila A TCC 46892 apresentou o mesmo padrão de restrição que as linhagens de referência N crassa NRRL 2223 e CCT 2680, assim como a maioria dos demais isolados. As linhagens AC4 e AC15 apresentaram padrão de restrição igual ao de N tetrasperma NRRL 2164. Os perfis de restrição do gene da proteína histona, his-3 obtido com as enzimas Dde I e Hae III, permitiram a diferenciação das duas espécies N. sitophila NRRL 2884, CCT 0045 e N. crassa NRRL 2223, CCT 2680. A linhagem N sitophila ATCC 46892 produtora de aroma, as linhagens N crassa NRRL 2223, CCT 2680, e as linhagens de Neurospora isoladas do mesmo local (Maranhão) apresentaram perfis idênticos de restrição. Os fragmentos amplificados na região conservada 288 não apresentaram polimorfismo com nenhuma das enzimas em estudo. Os resultados da avaliação sensorial indicaram que as linhagens de Neurospora isoladas do beiju de mandioca, apresentam características aromáticas muito semelhantes à da linhagem produtora de aroma de frutas N sitophila ATCC 46892. Os métodos moleculares e a taxonomia polifásica forneceram informações referentes ao grupo de linhagens de Neurospora obtidas do mesmo substrato da linhagem produtora de aroma N. sitophila ATCC 46892, reforçando o uso desses métodos na caracterização de microrganismos associados à produção de aroma, podendo auxiliar na escolha de linhagens para futuros estudos envolvendo a produção e aplicação tecnológica Abstract: Polyphasic taxonomic studies were done with twenty-two Neurospora strains isolated from cassava beiju and burned vegetation in Maranhão and São Paulo states. Strains were characterized regarding morphology, protein profiles and polymorphisms of 18S, 28S and 18S-28S rDNA spacer fragment, histone H3-1 gene, and aroma production. References strains: N crassa NRRL 2223, CCT 2680 (=ATCC 24698); NRRL 2884 (=ATCC 36935), CCT 0045 (=NRRL 2884); N. intermedia (N. sitophila ATCC 36935) N. sitophila ATCC 46892 (aroma producer) and N. tetrasperma NRRL 2164, were also studied. Results obtained from morphological analyses suggested that the isolates comprised 7 different species. Strains from Maranhão were identified as N. sitophila but, except for strain AC9, identified as N. crassa, whereas isolates from São Paulo were assigned to N. africana, N. crassa, N. dodgei, N. galapogensis, N. lineolata, N. sitophila, and N. tetrasperma. The analyses of total protein profiles agreed with the results from morphological analysis. Analysis of total protein profiles as well as spacer region digestion with Ava II endonuclease allowed the grouping of N sitophila A TCC 46892 aroma producer strain with the isolates of Neurospora spp. originated of same substrate (cassava beiju) and local (Maranhão). These strains formed a group distinct from the reference strains and from the others isolates. Digestion of 18S rDNA with restriction enzyme Hae III resulted in different patterns for the three reference strains in study. N sitophila ATCC 46892 aroma producer strain, reference strains N. crassa NRRL 2223, CCT 2680 and most of the isolates presented the same restriction patterns. AC4 and AC15 strains and the N. tetrasperma NRRL 2164 reference strain presented identical restriction patterns. Restriction profiles of the histone protein gene, his-3 obtained with Dde I and Hae III enzymes allowed the differentiation of the two species N. sitophila NRRL 2884, CCT 0045 and N. crassa NRRL 2223, CCT 2680. N. sitophila ATCC 46892 aroma producer strain, N crassa NRRL 2223, CCT 2680 strains and Neurospora strains isolated from same local (Maranhão) presented identical restriction pattern. Amplified fragments from 28S rDNA conserved region with studied enzymes did not present polymorphism. Sensorial evaluation indicated that Neurospora strains isolated of cassava beiju show aromatic characteristics similar to that of N sitophila ATCC 46892, producer of fruit aroma strain. Molecular methods and the polyphasic taxonomy provided information for the Neurospora group originated from the same substrate of the N. sitophila ATCC 46892 aroma producer strains. These methods corroborate characterization of microorganisms associated to production of aroma, and could was be collaborate useful with selection of strains for future studies related with technological production and application Doutorado Doutor em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

17

Pinheiro, Denise Maria. "Biotransformação de terpenos em compostos de aroma." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256712.

Testo completo

Abstract (sommario):

Orientador: Glaucia Maria Pastore Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-03T20:52:48Z (GMT). No. of bitstreams: 1 Pinheiro_DeniseMaria_D.pdf: 8292543 bytes, checksum: f388836a2d16e3e97cec519efcedbbcb (MD5) Previous issue date: 2004 Doutorado

Gli stili APA, Harvard, Vancouver, ISO e altri

18

CHIARELLI, PERDOMO IGOR. "PRODUCTION OF NATURAL AROMA COMPOUNDS BY BIOCATALYSIS." Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/694810.

Testo completo

Abstract (sommario):

Gli esteri svolgono un ruolo rilevante nell'industria alimentare, sono tra i composti più importanti e versatili di aromi e fragranze naturali in alimenti, bevande e cosmetici. La loro preparazione da substrati naturali e l'utilizzo di bioprocessi (eg. fermentazione o reazioni enzimatiche) è attrattivo, perché il prodotto finale può essere etichettato e commercializzato in UE e USA come naturale. Pertanto, nuovi approcci biotecnologici per ottenere aromi sono desiderati, una volta che siano efficienti e sostenibili. Molti esteri con proprietà aromatiche possono essere ottenuti enzimaticamente usando lipasi che catalizzano reazioni di esterificazione, transesterificazione o interesterificazione. In questa tesi di dottorato abbiamo sviluppato due sistemi per la produzione di esteri con proprietà aromatiche: 1) Un metodo biocatalitico per la preparazione enzimatica di diversi esteri con proprietà aromatiche da alcoli primari (isoamilico, n-esilico, geranilico, cinnamilico, 2-feniletilico e benzilico) ed esteri etilici naturalmente disponibili (formiato, acetato, propionato e butirrato). Le biotrasformazioni sono catalizzate da un'aciltransferasi di Mycobacterium smegmatis (MsAcT) e precedute da eccellenti rese (80- 97%) e brevi tempi di reazione (30-120 minuti), anche quando sono state utilizzate concentrazioni di substrato elevate (fino a 0,5 M). Questa strategia enzimatica rappresenta un'alternativa efficace all'applicazione delle lipasi nei solventi organici e un miglioramento significativo rispetto ai metodi già noti in termini di uso ridotto di solventi organici, aprendo la strada a una preparazione sostenibile ed efficiente degli agenti aromatizzanti naturali. 2) Un metodo biocatalitico con la lipasi legata al micelio liofilizzato di Aspergillus oryzae che catalizza l'esterificazione diretta di alcoli e acido acetico in solvente organico. Ha mostrato un'elevata stabilità verso substrati e prodotti. L'acqua prodotta durante l'esterificazione non ha influenzato in modo significativo l'equilibrio della reazione, consentendo conversioni elevate. Queste caratteristiche sono state sfruttate per preparare esteri con proprietà aromatiche dell'acetato (isoamil e cinnamil acetato) in sistemi in batch e continui. È stato sviluppato un continuous stirred tank membrane reactor (CST-MR) ovvero un reattore continuo a membrana sotto agitazione per garantire una buona produttività e un'elevata stabilità del biocatalizzatore. Entrambi i sistemi di produzione sono promettenti, rappresentano due diverse alternative e possono essere ulteriormente ottimizzati e scalati per gli interessi del settore. Esters play a significant role in the food industry, they are among the most important and versatile components of natural flavours and fragrances in food, drinks and cosmetics Their preparation starting from natural substrates and using bioprocesses (e.g., fermentation or enzymatic reactions) is appealing, since the final product can be labelled and commercialized in EU and USA as natural. Therefore, new biotechnological approaches for obtaining flavours are highly demanded as long as they are efficient and sustainable. Many flavour/fragrance esters can be enzymatically obtained using lipases that catalyse esterification, transesterification or interesterification reactions. In this PhD thesis we studied two systems for production of flavours esters: 1) A straightforward biocatalytic method for the enzymatic preparation of different flavour esters starting from primary alcohols (e.g., isoamyl, n-hexyl, geranyl, cinnamyl, 2-phenethyl, and benzyl alcohols) and naturally available ethyl esters (e.g., formate, acetate, propionate, and butyrate) was developed. The biotransformations are catalysed by an acyltransferase from Mycobacterium smegmatis (MsAcT) and preceded with excellent yields (80-97%) and short reaction times (30-120 minutes), even when high substrate concentrations (up to 0.5 M) were used. This enzymatic strategy represents an efficient alternative to the application of lipases in organic solvents and a significant improvement compared to already known methods in terms of reduced use of organic solvents, paving the way to a sustainable and efficient preparation of natural flavouring agents. 2) Mycelium-bound lipase of dry mycelium of Aspergillus oryzae catalysed direct esterification of alcohols and acetic acid in organic solvent, showing high stability towards substrates and products. Water produced during the esterification did not significantly affect the equilibrium of the reaction, allowing for high conversions. These features were exploited for preparing flavour-active acetate esters (e.g., isoamyl and cinnamyl acetate) in batch and continuous systems. A continuous stirred tank membrane reactor (CST-MR) was developed securing good reactor productivity and high biocatalyst stability. Both production systems are promising, represent two different alternatives and can be further optimized and scaled up for the interests of the industry.

Gli stili APA, Harvard, Vancouver, ISO e altri

19

Itobe, Takafumi. "Studies on Factors Affecting the Flavor Release from Foods: Development of New Approaches to Estimate the Flavor Release Characteristics." Kyoto University, 2017. http://hdl.handle.net/2433/225319.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

20

Kirsch, Lara [Verfasser]. "Impact of hot water extraction methods on key aroma compounds in beverages from differently roasted coffees and studies on the influence of single aroma compounds on the overall coffee aroma / Lara Kirsch." München : Verlag Dr. Hut, 2019. http://d-nb.info/1192568257/34.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

21

Kirsch, Sarah Lara [Verfasser]. "Impact of hot water extraction methods on key aroma compounds in beverages from differently roasted coffees and studies on the influence of single aroma compounds on the overall coffee aroma / Lara Kirsch." München : Verlag Dr. Hut, 2019. http://nbn-resolving.de/urn:nbn:de:101:1-2019080923381229335275.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

22

Molina, Gustavo 1983. "Biotechnological production of aroma compounds by the biotransformation of terpenes = Produção biotecnológica de compostos de aroma por biotransformação de terpenos." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254207.

Testo completo

Abstract (sommario):

Orientador: Gláucia Maria Pastore Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-25T05:52:01Z (GMT). No. of bitstreams: 1 Molina_Gustavo_D.pdf: 62790925 bytes, checksum: aac4f7324e48e27f7a1b9fdc0102ecd7 (MD5) Previous issue date: 2014 Resumo: Este trabalho de doutorado teve como principal objetivo estudar a produção biotecnológica de compostos de aroma a partir da biotransformação de terpenos, analisando potenciais biocatalisadores, processos bioquímicos diferenciados e a otimização das condições de processo envolvidas na produção destes aromas naturais para possíveis aplicações industriais. Inicialmente, o trabalho prático foi direcionado para uma série de estudos com o fungo Fusarium oxysporum 152B, visando complementar os recentes avanços alcançados pelo grupo de pesquisa na caracterização e otimização da bioconversão de R-(+)-limoneno em ?-terpineol. Desta forma, os resultados foram promissores, demonstrando o grande potencial e versatilidade deste fungo para a área, sendo que este biocatalisador foi capaz de produzir diferentes metabólitos a partir dos substratos S-(?)-limoneno, ?-pineno, ?-terpineno e linalol. Na sequência, o trabalho visou avaliar a bioconversão de S-(?)-limoneno para limoneno-1,2-diol em maiores detalhes. A produção de limoneno-1,2-diol, em condições não otimizadas, chegou a 1,2 g.L-1, sendo que foi detectada a continuação desta via metabólica quando este produto foi posteriormente metabolizado a 1-hidroxi-2- oxolimoneno, sugerindo que o fungo Fusarium oxysporum 152B possui uma via de degradação de limoneno recentemente descoberta. O trabalho prático visou também a otimização da produção de limoneno-1,2-diol por meio de uma estratégia sequencial de experimentos. Com base nas análises estatísticas, a produção deste composto a partir da bioconversão de S-(?)-limoneno pelo fungo Fusarium oxysporum 152B chegou a 3,7 g.L-1, utilizando pH 6,5, 5 g.L-1 de substrato, a 28 oC e 250 rpm de agitação. Além disso, esta foi a primeira descrição da utilização do resíduo agroindustrial conhecido como manipueira, originada ao longo do processamento da mandioca, para a produção de biomassa deste fungo, bem como uma das maiores concentrações de limoneno-1,2-diol reportadas na literatura específica. Além disso, o trabalho conduzido visou realizar uma série de comparações práticas entre a biotransformação de R-(+)-limoneno a ?-terpineol e a bioconversão de S-(?)-limoneno a limoneno-1,2-diol, pela mesma linhagem. Adicionalmente, este foi o primeiro trabalho que analisou as diferenças ultraestruturais causadas no biocatalisador ao longo do processo de bioconversão destes substratos, por meio de microscopia eletrônica de varredura e transmissão. Finalmente, foi estudada a otimização da produção de ?-terpineol, a partir da biotransformação de limoneno, utilizando o biocatalisador reconhecido como Sphingobium sp. Após o trabalho prático e análise estatística dos dados, observou-se que as melhores condições para desenvolvimento deste processo foram pH 7,0, concentração de limoneno de 350 g.L-1, agitação de 200 rpm e 28 oC. Nestas condições, a produção deste álcool monoterpênico chegou a 500 g.L-1, que pode ser considerada como a maior concentração de ?-terpineol já relatada na bibliografia de processos biotecnológicos. Abstract: This work aimed to study the biotechnological production of aroma compounds from the biotransformation of terpenes, analyzing potential biocatalysts, biochemical processes and optimization of process conditions involved in the production of natural flavors for industrial applications. Initially, the practical work was directed to a series of studies with the fungal strain Fusarium oxysporum 152B, aiming to enhance the knowledge obtained in recent advances achieved by our research group in the characterization and optimization of the biotransformation of R-(+)-limonene into ?-terpineol. Thus, the results were promising, showing the great potential and versatility of this fungus to the specific area, and this biocatalyst was able to produce new metabolites from substrates S-(?)-limonene, ?-pinene, ?-terpinene and linalool. In the sequence, this study aimed at assessing the bioconversion of S-(?)-limonene into limonene-1,2-diol in greater detail. Thus, chapters 3, 4 and 5 were designed to a better characterization of this pathway. The production of this compound under non-optimized conditions, reached 1.2 gL-1, and the continuation of this pathway has been detected when this product was subsequently metabolized to 1-hydroxy-2-oxolimonene, suggesting that the fungus Fusarium oxysporum 152B might have a limonene degradation pathway only recently discovered. The practical work also conducted an extensive optimization of the production of limonene-1,2-diol by means of a sequential strategy. Based on statistical analyzes, the production of this compound from the bioconversion of S-(?)-limonene by the fungus Fusarium oxysporum 152B reached 3.7 gL-1, using pH 6.5, 5 gL-1 of substrate at 28 ° C and 250 rpm agitation. Moreover, this is the first description of the use of agroindustrial residue known as cassava wastewater, for the production of this fungal biomass, as well as one of the highest concentration of biotechnological limonene-1,2-diol reported in the specific literature. In addition, the research conducted aimed to perform a series of comparisons between practical conditions involved in the biotransformation of R-(+)-limonene into ?-terpineol, and the bioconversion of S-(?)-limonene into limonene-1,2-diol, for the same strain. Additionally, this is the first study that reported the ultrastructural differences along the bioconversion process of these substrates by means of scanning and transmission electron microscopy. Finally, this work evaluated the optimization of the production of ?-terpineol from the biotransformation of limonene using the biocatalyst recognized as Sphingobium sp. After the practical work and statistical analysis, it was observed that the best conditions for developing this process were pH 7.0, concentration of limonene 350 g L-1, agitation at 200 rpm and 28 oC. Accordingly, the production of the monoterpe alcohol reached 500 g.L-1, which can be considered as the highest concentration of ?-terpineol already reported in the literature for biotechnological processes. Doutorado Ciência de Alimentos Doutor em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

23

Pearson, Kris S. K. "The effect of dispersion mechanisms on aroma delivery." Thesis, University of Nottingham, 2005. http://eprints.nottingham.ac.uk/12881/.

Testo completo

Abstract (sommario):

Dispersion of aroma compounds in food matrices is a common process in the production of many food products. However, the degrees of dispersion on the distribution and subsequent release of these compounds during consumption may have considerable consequences for perception of these flavours. This thesis investigates the effects of a range of dispersion techniques on the delivery and release of aroma compounds from several solid and semi-solid matrices which commonly contain added flavourings. Dispersion was achieved on three main scales ranging from molecular, through micro regions to physical separation or layering. The effects of different levels of mixing were assessed by measuring aroma release in vitro and in vivo via APci-MS. Having defined the stages of mixing, systems were developed to measure the influences of different dispersion techniques on aroma delivery. Layering to physically separate homogenous aroma-rich layers showed no significant effects on aroma release or perception from gelatine sucrose gels. It seems that mastication is very effective in re-mixing these systems and, in vivo there is no difference in aroma release. Although the degree of mixing could be controlled using a static mixer system for yoghurts, no effects of the different levels of mixing were observed on aroma release. Stirred yoghurts showed that mixing could influence equilibrium headspace concentrations but overall release in vivo was inconclusive. Sample selection in these systems may be important for influencing perception. Visual and textural cues may be more important for perception, in these mixing examples, than aroma release. Using co-solvents as dispersion agents significantly increased the ease of dispersion of a range of aroma compounds. Static headspace analysis confirmed that all the carrier solvents influenced the partition of aroma compounds and in vivo release from model confectionery systems. Increasing solvent concentration increased the solubility of a range of aroma compounds in the liquid phase. Release from gels was also influenced by the presence of solvents with hydrophobic aroma compounds showing patterns of release similar to those of hydrophilic compounds when dispersed using solvents. Finally, this work studied release from phase separated systems where the aroma compound was present as a microdroplet. Release was very intense and rapid and was investigated in aqueous solutions and gelatine-sucrose gels. In this case the release mechanism was not the conventional air-liquid partition but was based on direct release from the air-liquid interface. Release was dependent on both hydrophobicity and vapour pressure.

Gli stili APA, Harvard, Vancouver, ISO e altri

24

Jublot, Lionel. "Aroma analysis using novel direct mass spectrometric systems." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433978.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

25

Rodríguez, Díaz María Alejandra. "Odotipo: El aroma que identifica a la marca." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2018. http://hdl.handle.net/10757/625508.

Testo completo

Abstract (sommario):

El dinamismo y la saturación en el mercado exigen que las marcas involucren nuevas alternativas para conquistar compradores y retener clientes cada vez más exigentes. Frente a ello, las marcas se han enfocado en la importancia de la relación de los sentidos y los consumidores. De allí nace la oportunidad de orientarse hacia los sentidos menos explotados, como el olfato. Este sentido se destaca por su gran nivel de recordación y los beneficios de asociación que brinda a la marca. De esta manera, puede formar parte de los elementos de identidad de marca, denominado como odotipo, el cual se define como la forma aromática que identifica a una marca. Con miras a identificar y analizar las condiciones para la implementación del odotipo como elemento de la identidad de marca, se realizó una investigación de tipo cualitativa, la cual se llevó a cabo a través de aplicación de entrevistas semiestructuradas a especialistas en áreas de branding y/o planeamiento. Como resultados, en el cuarto capítulo se presenta el análisis de la información recaudada, así como la explicación de cómo esta contribuye a cumplir con los objetivos de la investigación. Finalmente, se pudo llegar a las conclusiones y recomendaciones útiles para todo aquel que esté interesado en implementar el odotipo como elemento de identidad de marca. The market dynamism and saturation of it demands that brands incorporate new strategies to attract new buyers and retain more demanding costumers. For these reasons, brands have focused in the importance of how are related consumers and their senses. As a result, the opportunity to use one of the less exploited senses is born: the smell. This sense outstands because of its remembrance level and association with brand benefits. Therefore, the smell can be considerated as one of the elements of the brand identity, it’s called odotype and can be defined as the aromatic form that identify a brand. This study was realized In order to analyze the conditions for an odotype implementation as a brand element; a qualitative methodology was used by the application of semi-unstructured interviews to a branding and planning specialists. As a result, chapter four presents the analysis of the information collected and explains how it contributes to other investigation objectives. Finally conclusions and useful recommendations were exposed to every interested in odotype implementation as an element of brand identity. Tesis

Gli stili APA, Harvard, Vancouver, ISO e altri

26

Fairbairn, Samantha. "Stress, fermentation performance and aroma production by yeast." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20336.

Testo completo

Abstract (sommario):

Thesis (MSc)--Stellenbosch University, 2012. ENGLISH ABSTRACT: Yeast strains contend with numerous stresses during winemaking. An inability to perceive and initiate the physiological changes needed to adapt to stress, has been linked to slow or incomplete (residual sugar > 4 g/L) fermentations. Wine yeast strains differ in genotype; this is manifested as differences in their stress tolerance, and fermentation performance. The first goal of this study was to evaluate how the initial sugar (200 or 240 g/L) and nitrogen (50, 100, 250, or 400 mg/L) content, and the fermentation temperature (15°C or 20°C) affected the fermentation performance of 17 commercial wine yeast strains. Fermentation performance was evaluated based on the fermentation kinetics (lag phase, maximum fermentation rate and total weight loss by CO2 evolution), residual sugar content and yeast dry weight. The results demonstrate that the fermentation performances of commercial yeast cultures are significantly and differently affected by initial nitrogen and sugar levels, as well as the fermentation temperature. Additionally, excess nitrogen had a negative impact on the fermentation kinetics and sugar consumption. Nitrogen deficiency is a common cause of slow and incomplete fermentations, as it affects yeast growth and thus fermentation rates. Nitrogen supplements are routinely added at the onset of fermentation, reducing the risk of problematic fermentations. Therefore characterising the fermentative ability of a strain over a range of oenologically relevant conditions, could aid winemakers in selecting a yeast strain capable of fermenting a grape must (of known sugar and nitrogen levels) to completion at the desired fermentation temperature. Investigations on fermentation related stress generally focus on its influence on fermentation rate and sugar consumption. However, from a winemaking perspective, the strain’s ability to produce the desired volatile aroma compounds is equally important. Yet, literature provides little insight into the influence stress has on the volatile aroma profile; this is surprising as wine aroma is closely linked to wine quality and consumer liking. The final goal of this study was to evaluate changes to the volatile aroma profiles produced by five commercial yeast strains, in response to hyperosmotic and temperature stress. The concentrations of the aroma compounds were quantified using a gas chromatograph coupled to a flame ionization detector. The results show that hyperosmotic and temperature stress caused significant changes in the levels of a number of aroma compounds. Furthermore, the changes observed differed among the evaluated strains, as well as for the fermentation stress treatments studied. Future aims should be directed towards the potential application of yeast strain selection as a means to avoid problematic fermentations in grape must; in addition to the further characterisation of the relationship between stress and the resultant volatile aroma profile in wine. AFRIKAANSE OPSOMMING: Gisrasse moet verskeie stresfaktore afweer tydens die wynmaak proses. Die onvermoë van ‘n wyngis om stres waar te neem en die nodige fisiologiese veranderinge te inisieer om aan te pas by die strestoestande word met slepende of onvolledige fermentasies (met ‘n residuele suiker van meer as 4 g/L) geassosieer. Wyngisrasse verkil in genotipe; wat as groot verskille in die graad van strestoleransie, en dus ook fermentasie sukses geopenbaar word. Die eerste doelwit van hierdie studie was om te evalueer hoe die suiker (200 of 240 g/L) en stikstof (50, 100, 250, of 400 mg/L), asook die fermentasie temperatuur (15°C of 20°C) die fermentasie prestasie van 17 kommersiële wyngiskulture beïnvloed. Die sukses van fermentasie is geëvalueer op grond van fermentasie kinetika (sloerfase, maksimum fermentasiespoed en totale gewigsverlies as CO2 verlies), die residuele suiker inhoud en die gis droë massa. Die resultate demonstreer dat die fermentasie sukses van kommersiële giskulture beduidend en verskillend beïnvloed word deur die aanvangsstikstof en – suikerkonsentrasies, asook die fermentasie temperatuur. Daarbenewens, wanneer stikstof in oormaat teenwoordig is kan dit ‘n negatiewe impak op fermentasietempo en suiker metabolisme hê. Beperkende vlakke van stikstof ‘n algemene oorsaak van slepende of onvolledige fermentasies, aangesien stikstof die groei en gevolglik ook die fermentasiespoed van gis beïnvloed. Stikstofaanvullings word dikwels tot druiwemos toegevoeg aan die begin van gisting, wat die risiko van probleemfermentasies verlaag. Dus kan die karakterisering van die fermentasievermoë van ‘n gisras vir ‘n reeks wynkundig relevante kondisies die wynmaker help om ‘n gisras te selekteer wat in staat is om ‘n druiwemos (waarvan die suiker en stikstofvlakke bekend is) droog te gis by die gewenste temperatuur. Meeste studies wat fermentasieverwante stress ondersoek, fokus op die die invloed daarvan op fermentasietempo en suikerverbruik. Van ‘n wynmaakperspektief is die gis se vermoë om die gewensde vlugtige aroma komponente te produseer egter ewe belangrik as die vermoë om fermentasie te voltooi. Tog verskaf die literatuur min insig tot die invloed van stres op die vlugtige aromaprofiel; wat verbasend is aangesien die aromaprofiel ‘n belangrike faktor is van die waargenome wynkwaliteit en daarom ook verbruikersvoorkeur. Die finale doelwit van hierdie projek was om die veranderinge tot die vlugtige aromaprofiel geproduseer deur vyf kommersiële gisrasse in reaksie op hiperosmotiese stres en temperatuur stres te evalueer. Die konsentrasies van die aromakomponente is gekwantifiseer deur gas chromatografie gekoppel aan vlam‐ioniserende deteksie. Die resultate wys dat hiperosmotiese‐ en temperatuur stres beduidende veranderinge meebring in die vlakke van ‘n aantal aromakomponente. Verder is die waargenome veranderinge ook verskillend vir die geëvalueerde gisrasse, asook vir die verskille stresbehandelings wat ondersoek is. Toekomstige studies behoort gerig te wees op die toepassing van gis seleksie om potensiële probleemfermentasies in druiwemos te voorkom; asook die verdere karakterisering van die verhouding tussen omgewingstresfaktore en die gevolglike vlugtige aromaprofiel in wyn.

Gli stili APA, Harvard, Vancouver, ISO e altri

27

Santos, Sandra Isabel Fidalgo dos. "Desenvolvimento de um azeite com aroma a limão." Master's thesis, Universidade de Aveiro, 2010. http://hdl.handle.net/10773/3973.

Testo completo

Abstract (sommario):

Mestrado em Biotecnologia Foram preparadas amostras de azeite aromatizadas com casca de limão, uma com 10,5g/kg à qual foram retiradas as cascas após 7 dias e outra com 5g/kg onde a casca permaneceu ao longo do estudo, tendo a sua estabilidade sido acompanhada ao longo de 60 dias.Verificou-se que o índice de acidez de ambas as amostras se manteve estável ao longo de todo o estudo, no entanto o índice de peróxidos sofreu variação ao longo do tempo atingindo, no final do estudo, valores acima dos regulamentados para este parâmetro (20meq.O2/kg).A quantidade de limoneno extraída da casca de limão para o azeite, revela valores sem oscilações significativas, não havendo portanto perdas ao longo do tempo. A PCA (Análise de Componentes Principais) aplicada aos espectros de FTIR permitiu classificar o azeite aromatizado ao longo do tempo mostrando uma separação entre azeites com valores de índice de peróxido inferior e superior a 20meq.O2/kg). A utilização da Alta Pressão (AP) na extracção de limoneno, permitiu concluir que as amostras pressurizadas apresentam um teor de limoneno mais elevado do que as aromatizadas à pressão atmosférica. Os valores de extracção mais elevados (±30Ig/kg) foram obtidos a 100 MPa durante 15 minutos, tendo-se obtido, com estas condições experimentais, quase o dobro da quantidade de limoneno extraída à pressão atmosférica. Procedeu-se ainda à extracção do azeite recorrendo a AP reduzindo a quantidade de azeite envolvida (pressurização em saco). Os resultados obtidos com frasco, concluindo-se que existe similaridade no que diz respeito à quantidade de limoneno extraída. Nas mesmas condições, foi realizado um ensaio que permitiu avaliar a quantidade de casca de limão a partir da qual, mantendo-se a quantidade de azeite, se atinge o equilíbrio de extracção, o que em termos industriais permitirá a diminuição de custos inerentes à redução de matéria-prima. Verificou-se que os valores determinados para o índice de acidez e índice de peróxidos do azeite submetido a AP, encontram-se dentro dos valores regulamentados para esses parâmetros químicos, mesmo após os 30 dias. Sugere-se ainda, como alternativa industrial à aromatização de azeite com casca de limão, a preparação de uma amostra de azeite intensamente aromatizado com limoneno de casca de limão, podendo ser usada em diluições, ajustando-se a quantidade de limoneno desejada e sem que o azeite necessite de estar em contacto com as cascas de limão. Was performed flavoring of olive oil with citric peel, with 10,5g/kg, that we retired the peel after 7 days and another with 5g/kg, that stay with peel throughout the study, and the stability has been accompained for aproximatelly 60 days.It was investigated that both samples acidity was kept stable throughout the study, however peroxid level varies along the time, and in the end of the investigation it is above to the allowed (20meq.O2/kg).Limonene quantity extracted doesn´t show any significant variations, and obviously no losses over the time. PCA (Principal Component Analysis) applied to FTIR spectres allowed peel lemon with fragrance olive to be classified along the time, and clear results differentiation could be visualized between olive oils with values lower and above to 20meq.O2/kg. (HP) High Pressure use in limonene extraction allowed conclusions such as : pressurized samples present a higher limonene content comparing to samples flavored at atmospheric pressure. Extraction results higher (±30Ig/kg) were obtained to 100 MPa for 15 minutes, being almost double of atmosferic pressure extracted quantity taken. To complement the investigation, AP extraction was performed, reducing olive oil quantities involved (bag pressurization). Comparing results it is concluded that there is a similar, to the amount of limeneextracted.A trial was performed in the same conditions, where lemon peel could be analysed keeping. Keeping the same olive oil quantity extraction equilibrium is achieved, which allows to minimize raw material costs. Acidity índex results and peroxid índex submited to AP are under the legislation, even after 30 days. Lemon peel intense flavoring oil with limonene is suggested as alternative to industrialized lemon peel olive fragrance. It can be used in dilutions adjusting required limonene ammont, and through this method olive don´t need to be in contact with peels.

Gli stili APA, Harvard, Vancouver, ISO e altri

28

Gan, H. H. "Aroma-matrix interaction in food : an APCI approach." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/29071/.

Testo completo

Abstract (sommario):

An overview is presented of the principle, scope and major applications to date of the use of atmospheric pressure chemical ionisation mass spectrometry (APCI-MS) for monitoring the kinetics of release of flavour volatiles in real time. There are four major areas in this thesis that extend from the measurement of flavour molecular mobility in sugar solutions, to the investigation of APCI-MS as a diagnostic tool for classifying apple cultivars and predicting age of cheese. Headspace techniques are the most extensively employed techniques in food analysis to measure volatile compounds, which play a central role in the perceived quality of food. The use of APCI-MS to measure aroma headspace availability with the addition of solutes was evaluated for two sugars of differing chain lengths (fructose and fructooligosaccharide (FOS)). In vitro aroma release was investigated at equilibrium using APCI-MS. An increase in the concentration of fructose above 25 % (w /w) was shown to significantly (p < 0.05) increase the release of ethyl butyrate, ethyl acetate and benzaldehyde into the gas phase above the aqueous solutions. Proton nuclear magnetic resonance (1 H NMR) was used to investigate the nature of solvent-sugar-aroma interactions with a view to explain the differential availability of aroma volatiles in sweetened and biopolymer rich solutions. The T1 relaxation times, and diffusion coefficients, provided preliminary clues as to the interactions between water, aroma and biopolymer. In the case of in vivo measurement, aroma perception was dependent on two key factors – firstly the equilibrium gas phase concentration of the aroma compounds within the oral/ nasal cavity and secondly the dynamic interaction of the compound with food and saliva (persistence). The overall process was influenced by the properties of the flavour compounds (i.e. its hydrophobicity) and the physiological conditions of the mouth, nose and throat during consumption of the food. A comparison was made between the intensities of anisaldehyde, furaneol and guaiacol in the headspace above simple solutions of water, to demonstrate the impact of matrix on flavour release in a frozen dairy dessert. The oral and nasal persistence of aromas following swallowing samples of a model frozen dairy dessert was investigated by collecting expired air from nose and mouth over 60-seconds. The decay curves (which illustrates persistence) of volatiles in breath showed that furaneol was the most persistent aroma, due to its hydrophilic nature and low volatility, that is expressed by the vapour pressure values of the pure compound. It is presumed to interact with the nasal mucosa, thereby prolonging persistence and potentially offering a significantly different perceptual profile to the less persistent compounds (Hodgson, Parker, Linforth, & Taylor, 2004). Thus, real time APCI-MS headspace data could be used to validate mathematical modelling of flavour release (Harvey & Barra, 2003). The feasibility of APCI-MS volatile compound fingerprinting in conjunction with chemometrics as a new strategy for rapid and non-destructive food classification was demonstrated when 202 clarified monovarietal juices extracted from apples differing in their botanical and geographical origins were characterised. Partial Least Square-Linear Discriminant Analysis (PLS-LDA) gave 100 % correct classification for the categorization by cultivar. Another PLS regression model was built to interpret and predict the age of Cheddar using headspace data from GC-MS and APCI-MS. The RMSEP and R2 values for the prediction model were 3.94 and 0.85 respectively. This further established the applicability of multivariate statistical technique as a tool to monitor the quality of foodstuff. Throughout the thesis, recommendations regarding practical implications for APCI-MS analysis and applications are demonstrated and discussed.

Gli stili APA, Harvard, Vancouver, ISO e altri

29

Blackford, Christopher Lawrence. "Contribution of grape berry lipids to wine aroma." Thesis, Blackford, Christopher Lawrence (2020) Contribution of grape berry lipids to wine aroma. PhD thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/56052/.

Testo completo

Abstract (sommario):

Understanding how the composition of wine grapes influences the formation of wine volatiles is important for predicting and manipulating wine quality. The objective of this research was to develop an understanding of how non-varietal wine aroma compounds are affected by compounds sourced from grapes. Chemically defined grape juice musts were supplemented with material of interest and the volatile profile of the fermented wines analysed with head-space solid phase micro-extraction (HS-SPME) gas chromatography-mass spectrometry (GC-MS). Supplementing model must with different grape tissues was carried out to determine where volatile-influencing compounds are located in the berries, and variations in amino acid and lipid profiles identified as probable influences on wine aromas made by yeast. In order to isolate and identify grape compounds that increase fatty acid ethyl ester (FAEE) concentrations in wine, fractions of grape extract were separated by liquid chromatography and used to supplement model musts, resulting in the identification of the poly-unsaturated triglyceride TG 54:6 as a major component of fractions that induced high FAEE production during fermentation. The effect of supplementing model must with glycero-lipids on FAEE production was investigated and a positive impact of exogenous poly-unsaturated glycero-lipids on yeast-mediated FAEE production confirmed. A lipidomic profiling study of grape tissues, and of berry and seed development, was carried out by positive-mode liquid chromatography quadrupole time-of-flight MS (LC-QTOFMS). This study indicated: that there are few differences in lipid profile between mature Riesling and Cabernet Sauvignon grapes; that seeds and berry tissues have distinctive lipid profiles; and that lipid profiles change during berry development in both seeds and berry tissues. The results of these studies highlight the need for research into establishing optimal grape lipid profiles to produce wines with targeted wine aroma profiles.

Gli stili APA, Harvard, Vancouver, ISO e altri

30

Dionísio, Ana Paula. "Produção e estudo biológico de compostos de aromas obtidos a partir da biotransformação de carotenóides." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256730.

Testo completo

Abstract (sommario):

Orientador: Gláucia Maria Pastore Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-16T13:42:05Z (GMT). No. of bitstreams: 1 Dionisio_AnaPaula_D.pdf: 1301675 bytes, checksum: 2a24cee538b10a80523c9d76b57eb295 (MD5) Previous issue date: 2010 Resumo: A biotransformação de carotenóides é um campo de crescente interesse para a indústria de aromas, uma vez que podem ser obtidos compostos considerados como ¿naturais¿, de grande aplicabilidade industrial e que podem apresentar, em muitos casos, propriedades biológicas interessantes. Desta forma, o objetivo do presente trabalho foi efetuar um estudo de biotransformação de carotenóides seguida de uma otimização do processo, avaliar o uso de sub-produtos industriais para barateamento do processo, realizar a biotransformação de outros substratos terpênicos para formação de compostos voláteis e por fim, estudar as propriedades biológicas dos produtos voláteis derivados de carotenóides. O capítulo 1 apresenta uma revisão bilbiográfica sobre bio-oxidação de terpenos, focando especialmente no uso monoterpenos e b-caroteno como substrato. O capítulo 2 trata do isolamento de micro-organismos a partir de fontes naturais ricas em b-caroteno. Das mais de 400 linhagens avaliadas, cerca de 60 apresentaram um potencial para biotransformação de carotenóides, evidenciado por um halo de degradação característico formado ao redor da colônia inoculada em uma placa contendo b-caroteno. Em seguida, a técnica de microextração em fase sólida (SPME) foi usada para extração e concentração dos compostos voláteis formados na biotransformação pelas linhagens selecionadas, e os compostos foram identificados por CG-DIC e CG-EM. O estudo das variáveis envolvidas no processo de biotransformação de b-caroteno pela linhagem LB398APD é reportada no Capítulo 3. Para isso, um Placket-Burman (PB16) foi realizado inicialmente para seleção de variáveis, e seguindo o processo de planejamento experimental, um fatorial 22 com os parâmetros significativos do PB foi realizado. Em posse dos resultados da otimização, o Capítulo 4 retrata o uso de meios alternativos para o desenvolvimento de biomassa pela linhagem LB398APD. O micro-organismo possuiu um desenvolvimento em meio manipueira superior ao meio convencional, com condições ótimas do sistema alcançadas usando 60 % de manipueira, 30 °C e 300 rpm (produção de biomassa em 24h = 4,6g.L-1). Entretanto, quando glicerol foi usado como fonte de carbono, o desenvolvimento de biomassa não foi obtido com sucesso. Além dos ensaios usando b-caroteno como substrato, outros terpenos também foram avaliados com algumas linhagens fúngicas isoladas, e essa biotransformação é reportada no Capítulo 5. Carvona e carveol foram obtidos quando o limoneno foi usado como única fonte de carbono, e o uso de Paecilomyces sp. parece ser a primeira vez onde esse micro-organismo é reportado na literatura para ensaios e biotransformação. Por fim, o Capítulo 6 trata de alguns estudos ¿in vitro¿ com compostos de aromas derivados de carotenóides. Os resultados alcançados geram a possibilidade para esses compostos seres utilizados industrialmente como ¿aromas funcionais¿, pois apresentaram resultados extremamente interessantes quando esses terpenos foram usados em 12 células tumorais, representando resultados muitas vezes superiores ao controle positivo (doxorrubicina) Abstract: The biotransformation of carotenoids is a field of growing interest to the flavor industry, once the compounds obtained can be labeled as "natural", with high industrial applicability and that may present, in many cases, interesting biological properties. Chapter 1 reviews a variety of techniques developed till the present days for the oxidation of terpenes, especially monoterpenes and ß-carotene, to volatile compounds. In sequence, Chapter 2 deals with the screening of microorganisms from natural sources rich in ß-carotene. Among more than 400 strains evaluated, 60 exhibited a potential for biotransformation of carotenoids, as evidenced by a characteristic degradation halo formed around the colonies inoculated on a plate containing ß-carotene. Afterwards, the solid phase microextraction technique (SPME) was used to extrain and concontrate the aroma compounds produced by the selected strains, and the analysis were conduced by GC-FID and GC-MS. The study of the variables involved in the biotransformation of ß- carotene by the LB398APD strain is reported in Chapter 3. For this, a Placket-Burman (PB16) was initially performed for the screening of the variables, and following the experimental design process, a 22 factor with the significant parameters selected in the PB was performed. In sequence, Chapter 4 shows the use of alternative culture media for the biomass development by the LB398APD strain. The microorganism demonstrated a development in the cassava wastewater media higher than in the conventional media, and the optimum system conditions were achieved by using 60 % of cassava wastewater, 30 °C and 300 rpm (biomass production in 24 hours = 4.6 gL-1). In addition to the tests using ß-carotene as substrate, other terpenes were also tested with some fungal strains, and this biotransformation is reported in Chapter 5. Carvone and carveol were obtained when limonene was used as the sole carbon source. The use of Paecilomyces sp. seems to be the first report in literature for biotransformation assays. Finally, Chapter 6 deals with some in vitro studies with carotenoids derived aroma compounds. The promising results create the possibility for such compounds to be used as "functional flavors" Doutorado Doutor em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

31

Sartor, Sabrina de Bona 1982. "Compostos voláteis em vinhos Chardonnay (Vitis vinifera L.) produzidos em diferentes regiões brasileiras." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254322.

Testo completo

Abstract (sommario):

Orientadores: Helena Teixeira Godoy, Rodrigo Ramos Catharino Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-24T08:04:00Z (GMT). No. of bitstreams: 1 Sartor_SabrinadeBona_D.pdf: 1858041 bytes, checksum: 4e7eb6a81d989128b6d6cccb656a5a9d (MD5) Previous issue date: 2014 Resumo: O aroma final de um vinho é formando por um grande número de compostos químicos voláteis, presentes em concentrações variáveis e detectáveis pelo sistema olfativo humano. O estudo da fração volátil de vinhos tem sido o objetivo de muitas iniciativas de estudo, sendo que as metodologias de pesquisa de compostos voláteis em vinhos compreendem etapas fundamentais, tais como: a extração dos compostos, a separação das diferentes moléculas por cromatografia gasosa acoplada à um sistema de detecção e posteriormente, a identificação e quantificação dos compostos voláteis. O objetivo deste trabalho foi extrair, identificar e quantificar os compostos voláteis de vinhos Chardonnay produzidos em diferentes regiões brasileiras utilizando microextração em fase sólida no modo de headspace (HS-SPME) e cromatografia gasosa acoplada à espectrometria de massas tandem (GC-MSMS). As amostras foram produzidas nas principais regiões vitícolas brasileiras: Serra Gaúcha e Campanha (Rio Grande do Sul), Serra Catarinense e Região de Altitude (Santa Catarina) e Sul de Minas (Minas Gerais). O método de extração de compostos de aroma foi desenvolvido usando a técnica de HS-SPME e GC-MS/MS e análise multivariada com delineamento composto central rotacional (CCRD) e metodologia de superfície de resposta para obtenção de um ponto ótimo de extração. As condições otimizadas foram temperatura (°C) e tempo (minutos) de extração. A otimização multivariada das condições de extração por HS-SPME permitiu avaliar os efeitos de tempo e temperatura de extração nesta metodologia, permitindo a obtenção de um ponto ótimo de extração, 30°C e 45 minutos, dos representantes das classes dos principais compostos voláteis presentes em vinhos Chardonnay. A análise qualitativa e quantitativa da fração volátil dos vinhos foi realizada usando a técnica de GC-MS/MS. O método foi validado e aplicado para a análise de 31 compostos voláteis nas amostras de vinhos Chardonnay. Destes compostos analisados, 30 foram utilizados para a realização de PCA e HCA visando a diferenciação regional dos vinhos. A Análise de Componentes Principais (PCA) e Análise de Agrupamento Hierárquico (HCA) foram realizadas com os dados obtidos. Os resultados obtidos demonstraram que as amostras produzidas em Minas Gerais e na Serra Gaúcha possuem marcadores olfativos herbáceos e vegetais, enquanto as amostras produzidas na região da Campanha/RS, Serra Catarinense e Região de Altitude/SC possuem marcadores florais e frutados, reforçando o papel da origem geográfica na formação e diferenciação do aroma dos vinhos analisados Abstract: Wine aroma wine is formed by a large number of volatile chemical compounds, present in variable concentrations and detectable by the human olfactory system.The study of the volatile fraction of wines has been the aim of many research studies and those analytical methods including basic steps, such as: isolation and extraction of matrix, separation and detect by gas chromatography coupled to a detection system and finally, the identification and quantification of the individual components. The aim of this study was to extract, identify and quantify the volatile compounds of brazilian Chardonnay wines, produced in different regions, using solid phase microextraction in headspace mode (HS-SPME) and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). Samples were produced in the main wine producing regions in Brazil: Serra Gaúcha and Campanha (Rio Grande do Sul state), Santa Catarinense and Região de Altitude (Santa Catarina state) and Sul de Minas (Minas Gerais state). A extraction method of aroma compounds was developed and optimized using HS-SPME and GC-MS/MS and multivariate central composite rotational design (CCRD) with response surface methodology to obtain an optimum extraction condition. The optimized conditions were temperature (°C) and time (minutes) of extraction. Multivariate optimization of extraction conditions for HS- SPME allowed to evaluate the effects of time and temperature of extraction allowing the achievement of the optimum extraction point of compounds representatives of the main classes of volatile compounds in Chardonnay wines. The optimum point observed is at temperature in 30 ° C and time in 45 minutes. A method for qualitative and quantitative analysis of the volatile fraction of wines was carried out using the technique of GC-MS/MS. The method was validated and used for the analysis of 31 volatile compounds in samples of Chardonnay wines. From compounds analyzed, 30 compounds were used to perform PCA and HCA targeting regional differentiation of wines. The Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were performed with the data obtained. The results showed that samples produced in Minas Gerais and Serra Gaúcha shows high concentration of compounds with vegetal and herbaceous notes. Meanwhile, samples of Campanha, Serra Catarinense and Região de Altitude shoes high concentration of compounds with floral and fruity notes. These results reinforce the role of geographical origin in the formation and differentiation of aroma in wines Doutorado Ciência de Alimentos Doutora em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

32

Paulino, Bruno Nicolau 1989. "Otimização de processos biotecnológicos para a produção de compostos de aroma a partir de substratos monoterpênicos = Optimization of biotechnological processes for the production of aroma compounds from monoterpenic substrates." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254209.

Testo completo

Abstract (sommario):

Orientador: Gláucia Maria Pastore Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-26T00:10:11Z (GMT). No. of bitstreams: 1 Paulino_BrunoNicolau_M.pdf: 3431534 bytes, checksum: 95854820504f050fe2c1dd2bb892df9f (MD5) Previous issue date: 2014 Resumo: A crescente demanda por processos que tenham impacto ambiental reduzido, rendimentos consideráveis e ainda custos minimizados recorrem à biotecnologia como uma ciência que pode tornar essa necessidade uma realidade. Processos biotecnológicos para a produção de compostos de interesse industrial como biocorantes, açúcares funcionais, biosurfactantes e biodiesel são uma tendência no meio científico e ganham destaque pela inovação, resultados e aplicações obtidos. O apelo comercial dos produtos biotecnológicos é outro fator que influencia as pesquisas haja vista que esses produtos são considerados naturais e tem-se comprovado que muitos deles apresentam atividades biológicas relevantes. O aroma é um importante atributo dos alimentos e pode ser produzido via biotecnológica a partir de substratos de baixo custo. A utilização de resíduos agro-industriais com alto teor nesses substratos, como por exemplo, resíduos ricos em monoterpenos são de grande interesse na biotecnologia de produção de aromas. Além disso, a utilização de micro-organismos isolados de diferentes fontes como biocatalisadores na produção desses compostos é outra perspectiva, muito explorada e ainda desafiadora. A biotransformação de monoterpenos para a produção de compostos de aroma é vantajosa quando comparada com a síntese química clássica. Contudo, alguns problemas ainda devem ser minimizados, como sensibilidade dos biocatalisadores à toxicidade dos substratos ou condições operacionais e baixos rendimentos. Assim, a seleção de novos biocatalisadores, como micro-organismos endofíticos, o uso de ferramentas de engenharia genética e a utilização de métodos estatísticos de otimização de processos são promissores e caracterizam-se como a nova vertente na área de bioaromas, contornando as desvantagens até então limitantes dos processos de biotransformação. Eles permitem em alguns casos, o aumento de escala e dessa forma a real aplicação da bioconversão microbiana na indústria. Assim, trabalhos que visem selecionar novos biocatalisadores é ainda uma necessidade e quando aliados a otimização de processos podem fornecer caminhos para que os rendimentos da bioconversão de monoterpenos sejam aumentados. Nesse contexto, o presente trabalho visou selecionar micro-organismos com potencial para a bioconversão de monoterpenos de baixo custo e presentes em grandes quantidades em resíduos agro-industriais, como 'alfa'-pineno e R-(+)-limoneno, para a produção de compostos de aroma valorizados comercialmente, S-(-)-verbenona e 'alfa'-terpineol. O capítulo 1 traz uma revisão sobre os compostos monoterpênicos, abordando suas características químico-estruturais, biossíntese e recentes aplicações terapêuticas, além do seu uso como substratos na biotecnologia de produção de compostos de aroma. O capítulo 2 é dividido em duas partes: a parte I mostra os resultados de um screening realizado com 81 linhagens de fungos isolados de diferentes fontes, entre eles, fungos endofíticos, utilizados no estudo do potencial de biotransformação de R-(+)-limoneno e 'alfa'-pineno. A parte II descreve a otimização do processo de produção de S-(-)-verbenona biotecnológica a partir de ?-pineno por uma linhagem de fungo endofítico, ainda não identificado, isolado da romã (Punica granatum). O uso de um Delineamento Composto Central Rotacional (DCCR) de 4 variáveis proporcionou o estabelecimento de condições mais favoráveis ao processo, elevando a concentração de verbenona que era de 66 mg.L-1 para aproximadamente 108 mg.L-1 em um dos ensaios do DCCR e em torno de 98 mg.L-1 no ensaio de validação. O capítulo 3 aborda a otimização do processo biotecnológico de produção de ?-terpineol a partir de R-(+)-limoneno pela linhagem Bacillus tequilensis isolada de resíduos de processamento de frutas cítricas. Após a otimização e validação do processo nas condições consideradas ótimas através da análise de superfícies de resposta, a concentração de ?-terpineol passou de 25 mg.L-1 para 85 mg.L-1. Portanto, os resultados obtidos no trabalho mostraram um ganho de rendimento nos processos de bioconversão de substratos monoterpênicos e que a otimização de processos é uma importante ferramenta para a melhoria das condições experimentais possibilitando trabalhos futuros que envolvam aumento de escala Abstract: The growing demand for processes that reduce environmental impacts, have high yields and costs minimized uses biotechnology as a science that can make this need into a reality. Biotechnological processes for the production of industrial interesting compounds, such as biocolorant, functional sugars, biosurfactants and biodiesel, are a trend in the scientific field and are highlighted by innovation, application and results obtained. The commercial appeal of biotechnological products is another factor that stimulates researches since these products are considered natural and has been proven that many of them presents significant biological activities. The flavor is an important attribute of food and can be produced through biotechnological processes from low-cost-substrates. The use of agro-industrial wastes with high content of these substrates, such as residues rich in monoterpenes, is of great interest in biotechnology. Furthermore, the use of micro-organisms isolated from several sources as biocatalysts in the production of flavor compounds is another well-explored and challenging perspective. The biotransformation of terpenes for aroma compounds production is advantageous when compared with chemical synthesis. However, there are still some problems that must be minimized like biocatalysts sensitivity, toxicity of substrates and low yields. Thus, the selection of new biocatalysts, such as endophytic micro-organisms, use of genetic engineering and statistical methods for optimization of processes are promising and characterize a new perspective in bioaromas field. Thereby, works that search for new biocatalysts are necessary and associated with optimization processes can improve the monoterpenes bioconvertion. In this context, the objective of this work was the screening and selection of micro-organisms that are able to realize the biotransformation of low cost monoterpenes, 'alfa'-pinene and limonene, into high-value aroma compounds, such as verbenone and 'alfa-terpineol. The chapter 1 presents a current review on monoterpenes, showing their chemical characteristics, biosynthesis and recent therapeutic applications, besides their potential use as substrates for bioflavor production. The chapter 2 is divides in two parts: the first one shows the results of the screening of 81 strains of fungi isolated from several sources, including endophytic strains, for biotransformation of limonene and ?-pinene. The second part describes the optimization process for biotechnological verbenone production from "alfa'-pinene by a non-indentified fungal strain, isolated from pomegranate (Punica granatum). The use of a central composite rotatable design (CCRD) of 4 variables provided the optimal conditions for this process, increasing the verbenone concentration from 66 mg.L-1 to 108 mg.L-1 in one of the CCRD assays and 98 mg.L-1 after validation. The chapter 3 also shows an optimization study, in this case using limonene as substrate and the product obtained was ?-terpineol. The biocatalyst used was a bacterial strain, identified as Bacillus tequilensis, isolated from citrus fruit processing waste. After the optimization and validation in the best conditions obtained through the surface response analysis, the concentration of ?-terpineol reached was 85 mg.L-1. Therefore, the results obtained in this work show an improve of the yields in the biotransformation of both monoterpenic substrates and that optimization of processes is an important tool for the progress of future works involving scale-up studies Mestrado Ciência de Alimentos Mestra em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

33

Teixeira, Roberta Miranda. "Otimização das condições de cultura para produção de acetoína por Hanseniaspora guilliermondii /." Florianópolis, SC, 1999. http://repositorio.ufsc.br/xmlui/handle/123456789/81061.

Testo completo

Abstract (sommario):

Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Made available in DSpace on 2012-10-18T22:27:13Z (GMT). No. of bitstreams: 0Bitstream added on 2016-01-09T04:16:00Z : No. of bitstreams: 1 151973.pdf: 10782459 bytes, checksum: f403101da283921cf7a942cb5ba38b0d (MD5) A síntese de acetoína por Hanseniaspora guilliermondii a partir de glicose como fonte de carbono sob condições aeróbias é estudada. Um planejamento experimental e análise de superfície de resposta são desenvolvidos para avaliar a influência da concentração inicial de glicose, temperatura e pH na produção de acetoína. Os ensaios foram desenvolvidos em frascos agitados contendo meio YM à temperatura controlada. Um monitoramento do consumo de glicose, produção de biomassa e metabólitos (acetoína, acetato de etila e etanol) foi realizado. Os efeitos da concentração inicial de glicose e da temperatura apresentaram-se significativos para a resposta concentração máxima em acetoína. Já para a resposta produtividade, a concentração inicial de glicose e a interação entre temperatura e pH foram os efeitos que apresentaram significância estatística. Modelos empíricos para a produtividade e concentração máxima de acetoína foram determinados, os quais demonstraram-se não só significativos, como também preditivos. A otimização do processo foi realizada determinando-se os pontos de máximo nas equações representativas dos modelos acima citados. As condições ótimas encontradas são concentração inicial de glicose de 63 g/l e temperatura de 28 oC para a obtenção de uma concentração máxima em acetoína, sendo esta em torno de 365 mg/l. O ponto máximo considerando a produtividade e a concentração de acetoína é encontrado nas condições de concentração inicial de glicose igual a 64 g/l, temperatura de 30 oC e pH de 4,5.

Gli stili APA, Harvard, Vancouver, ISO e altri

34

Solina, Marica, University of Western Sydney, of Science Technology and Environment College, and Centre for Advanced Food Research. "Investigations on aroma development in wheat and soy extrudates." THESIS_CSTE_CAFR_Solina_M.xml, 2001. http://handle.uws.edu.au:8081/1959.7/525.

Testo completo

Abstract (sommario):

The factors determining the generation of aroma in starch extrudates containing added ingredients with aroma precursors were elucidated. Analyses were performed using headspace analysis of raw materials and extrudates and subsequent analysis by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O. Study I described the volatile, amino acid and fatty acid profiles of Hydrolised vegetable protein (HVP)and Soy protein isolate (SPI). Studies II, III and IV descibed the volatiles developed from extrusion of different feedstocks under mild and extreme processing conditions. Wheat starch was chosen as the carrier.A comparison of the influence of the three different ingredients HVP, SPI and glucose, added to the starch feed, showed the formation of Strecker aldehydes and Maillard-type compounds were significantly affected by the addition of these ingredients. The work in this thesis demonstrated that the addition of ingredients such as HVP, SPI, glucose, cysteine, cysteine-HCI, modifies the aroma of wheat starch extrudates. Furthermore, it showed the changes in conditions of extrusion and pH will greatly influence the aroma profile of the products. Doctor of Philosophy (PhD)

Gli stili APA, Harvard, Vancouver, ISO e altri

35

Zhang, Chi. "Investigating aroma-taste-texture interactions in model food systems." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.523221.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

36

Pfeiffer, Johann C. "Crossmodal flavour perception : the impact of taste on aroma." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417965.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

37

Hodgson, Mike. "Aroma release and delivery : physiological and physico-chemical considerations." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417106.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

38

Cronje, Joan Christel. "Chemical characterisation of the aroma of honeybush (Cyclopia) species." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5157.

Testo completo

Abstract (sommario):

Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2010. ENGLISH ABSTRACT: Honeybush tea, also known as “South Africa’s sweetest tea”, is a herbal tea made from the leaves and twigs of Cyclopia spp., indigenous to the fynbos biome in the Western and Eastern Cape provinces of South Africa. The pleasant sweet aroma and taste of fermented honeybush, its low tannin content and the absence of caffeine have led to widespread interest in the commercial cultivation and processing of honeybush tea since the mid-1990s. Although more than 20 species of honeybush grow in the wild, only a few species are commercially exploited for the manufacture of tea. Currently the more prominent species are C. intermedia, C. subternata, C. genistoides, and C. sessiliflora. The present research contributes to a comprehensive honeybush research programme being conducted at the Agricultural Research Council (ARC) Infruitec-Nietvoorbij in South Africa. The first phase of the present study, using C. genistoides as representative species, was aimed at developing the necessary methodology for the analysis of extremely low concentrations of honeybush volatiles. A high-capacity headspace sample enrichment probe was applied successfully in conjunction with gas chromatography-mass spectrometry (GC-MS) to analyse the volatile organic compounds present in dry or infused unfermented and fermented honeybush. A total number of 255 volatile compounds were identified in unfermented and fermented honeybush, the majority of which are terpenoids (138; 54%) comprising mostly terpenes, terpene ketones, terpene alcohols and terpene ethers. Of the other compound classes, the aldehydes are the largest group, followed by esters, hydrocarbons and ketones. The stereochemistry of the identified compounds was determined whenever possible. This is the most comprehensive chemical characterisation of the volatile compounds in a South African herbal plant reported to date. A comparative study of green and fermented honeybush showed that the same compounds are, to a large extent, present in both, albeit in different relative concentrations. Not all of the identified honeybush volatiles are necessarily odour-active compounds contributing to the overall typical honeybush aroma. An important aspect of this research was thus the identification of the 46 odour-active compounds in fermented honeybush by means of gas chromatography-olfactometry (GC-O), using detection frequency and aroma extract dilution analysis methods. Fifteen of these compounds, mainly terpenoids, were singled out as the most intense individual contributors to the honeybush aroma based on consideration of all the relevant GC-O data. The odours of certain compounds, i.e. (6E,8Z)-megastigma-4,6,8-trien-3-one, (6E,8E)-megastigma- 4,6,8-trien-3-one, (7E)-megastigma-5,7,9-trien-4-one, 10-epi- -eudesmol, epi- -muurolol and epi- - cadinol, were perceived by GC-O assessors as typically honeybush-like. The quantitative GC-MS data of seven different Cyclopia samples (including four different species and variants thereof) were compared with respect to all the volatile components and particularly with respect to the odour-active compounds. Interesting variations were found in the concentrations of certain odour-active compounds in the various samples. The quantitative data obtained for the odour-active honeybush volatiles and data obtained from the sensory analysis of eight Cyclopia samples (including four different species and variants thereof) were subjected to statistical analysis and interesting associations between compounds with certain sensory aroma attributes were established. The present study has made a major contribution to the scientific knowledge regarding one of South Africa’s most popular indigenous herbal teas. AFRIKAANSE OPSOMMING: Heuningbostee, wat ook bekend staan as “Suid-Afrika se soetste tee”, word gemaak van die blare en takkies van Cyclopia spp. wat inheems is en voorkom in die fynbosbioom van die Wes- en Oos-Kaapprovinsies van Suid-Afrika. Die aangename soet smaak en aroma van gefermenteerde heuningbos, die lae tannnien-inhoud en die feit dat die tee kafeïenvry is, het gelei tot belangstelling in die kommersiële verbouing en prosessering van heuningbostee gedurende die 1990s. Meer as 20 heuningbosspesies kom in die natuur voor, maar slegs ‘n paar spesies word kommersieel verbou vir die vervaardiging van heuningbostee waarvan C. intermedia, C. subternata, C. genistoides en C. sessiliflora tans die belangrikste spesies is. Die navorsing maak deel uit van ‘n omvattende heuningbos navorsingsprogram wat onder leiding staan van die Landbounavorsingsraad Infruitec- Nietvoorbij in Suid-Afrika. In die eerste fase van die huidige studie is die nodige analitiese metodologie ontwikkel vir die monsterneming en analise van die vlugtige organiese verbindings wat in uiters lae konsentrasies in heuningbos voorkom, deur van ‘n verteenwoordigende spesie, C. genistoides, gebruik te maak. ‘n Sogenaamde “sample enrichment probe” (SEP) is ontwikkel en suksesvol in kombinasie met gaschromatografie-massaspektrometrie (GC-MS) aangewend vir die analise van die vlugtige verbindings aanwesig in die bodamp van sowel droë plantmateriaal as infusies van ongefermenteerde en gefermenteerde heuningbos. ‘n Totaal van 255 vlugtige verbindings is geïdentifiseer, waarvan die meeste hoofsaaklik terpenoïede is (138, 54%) en terpene, terpeenketone, terpeenalkohole en terpeeneters insluit. Die ander verbindingsgroepe, waarvan die aldehiede die grootste groep is, sluit in esters, koolwaterstowwe en ketone. Indien haalbaar, is die stereochemie van die geïdentifiseerde verbindings ook bepaal. Hierdie studie is die mees omvattende chemiese karakterisering van die vlugtige verbindings in ‘n Suid-Afrikaanse kruieplant wat tot dusver onderneem is. ‘n Vergelykende studie het getoon dat ongefermenteerde en gefermenteerde heuningbos tot ‘n groot mate dieselfde verbindings, hoewel in verskillende relatiewe konsentrasies, bevat. Nie al die geïdentifiseerde vlugtige verbindings in heuningbos is noodwendig aroma-aktiewe verbindings wat ‘n bydrae tot die algehele tipiese heuningbosaroma lewer nie en daarom was die identifisering van die 46 aroma-aktiewe verbindings in geferementeerde heuningbos deur gebruik te maak van gaschromatografie-olfaktometrie (GC-O) deur middel van deteksiefrekwensie en aroma ekstrak verdunningsanalise, ‘n belangrike aspek van die navorsing. Na oorweging van al die tersaaklike GC-O data is 15 van hierdie verbindings, hoofsaaklik terpenoïede, uitgesonder as die verbindings wat die belangrikste bydrae tot die heuningbosaroma lewer. Die reuke van sekere van die verbindings, nl. (6E,8Z)-megastigma-4,6,8-triën-3-oon, (6E,8E)-megastigma-4,6,8-triën-3-oon, (7E)-megastigma-5,7,9-triën-4-oon, 10-epi- -eudesmol, epi- -muurolol, en epi- -cadinol, is deur sommige van die GC-O paneellede as tipies heuningbosagtig beskryf. Die kwantitatiewe GC-MS data van sewe verskillende Cyclopia monsters (insluitende vier verskillende spesies en variante daarvan) is vergelyk met betrekking tot al die vlugtige verbindings, asook veral met betrekking tot die aroma-aktiewe verbindings. Interessante variasies in die konsentrasies van sekere aroma-aktiewe verbindings is in die verskillende monsters waargeneem. Die kwantitatiewe data van die aroma-aktiewe heuningbosverbindings en data verkry uit die sensoriese analise van agt Cyclopia monsters (insluitende vier verskillende spesies en variante daarvan), is onderwerp aan statistiese analises waaruit interessante assosiasies tussen verbindings met sekere sensoriese aroma-eienskappe waargeneem is. Hierdie studie lewer ‘n groot bydrae tot die wetenskaplike kennis aangaande een van Suid- Afrika se mees populêre inheemse kruietees.

Gli stili APA, Harvard, Vancouver, ISO e altri

39

Mehle, Hannah Mabel. "Impact of Storage Conditions on Pea Protein Isolate Aroma." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu157781271335699.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

40

Witte, Jens Christian. "Einfluss von glykosidischen Aromavorstufen auf das Aroma in Sekt." Göttingen Cuvillier, 2008. http://d-nb.info/992302234/04.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

41

Solina, Marica. "Investigations on aroma development in wheat and soy extrudates." Thesis, View thesis, 2001. http://handle.uws.edu.au:8081/1959.7/525.

Testo completo

Abstract (sommario):

The factors determining the generation of aroma in starch extrudates containing added ingredients with aroma precursors were elucidated. Analyses were performed using headspace analysis of raw materials and extrudates and subsequent analysis by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O. Study I described the volatile, amino acid and fatty acid profiles of Hydrolised vegetable protein (HVP)and Soy protein isolate (SPI). Studies II, III and IV descibed the volatiles developed from extrusion of different feedstocks under mild and extreme processing conditions. Wheat starch was chosen as the carrier.A comparison of the influence of the three different ingredients HVP, SPI and glucose, added to the starch feed, showed the formation of Strecker aldehydes and Maillard-type compounds were significantly affected by the addition of these ingredients. The work in this thesis demonstrated that the addition of ingredients such as HVP, SPI, glucose, cysteine, cysteine-HCI, modifies the aroma of wheat starch extrudates. Furthermore, it showed the changes in conditions of extrusion and pH will greatly influence the aroma profile of the products.

Gli stili APA, Harvard, Vancouver, ISO e altri

42

Solina, Marica. "Investigations on aroma development in wheat and soy extrudates /." View thesis, 2001. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20050810.131130/index.html.

Testo completo

Abstract (sommario):

Thesis (Ph.D.) -- University of Western Sydney, 2001. "A thesis submitted for the degree of Doctor of Philosophy" "Supervisory panel, Food Science Australia: Robert L. Johnson, Frank B. Whitfield, University of Western Sydney: Paul A. Baumgartner, Grant Wyllie" Bibliography : leaves 179-192.

Gli stili APA, Harvard, Vancouver, ISO e altri

43

Pimentel, Mariana Recco 1984. "Produção de compostos de aroma a partir da biotransformação de monoterpenos por pseudomonas = Production of aroma compounds through biotransformation of monoterpenes by pseudomonas." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256734.

Testo completo

Abstract (sommario):

Orientador: Gláucia Maria Pastore Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-21T12:20:16Z (GMT). No. of bitstreams: 1 Pimentel_MarianaRecco_M.pdf: 2621314 bytes, checksum: d6872d6164557c38b2fa7e53bccaddf0 (MD5) Previous issue date: 2012 Resumo: O aroma é responsável por grande parte do sabor de um alimento, e considerado um dos atributos mais importantes na aceitação do produto pelo consumidor. A preferência dos consumidores por produtos naturais tem incentivado o desenvolvimento de novos processos biotecnológicos para a produção de compostos de aroma naturais. A biotransformação de terpenos é uma alternativa promissora para a produção de aromas, visto que pode contornar alguns problemas associados a síntese química como a baixa geração de resíduos tóxicos e alta regio- e estéreo-seletividade das reações. Ademais, segundo a legislação brasileira, produtos obtidos por métodos microbiológicos podem ser rotulados como 'naturais' (ANVISA, Resolução nº 104, de 14 de maio de 1999). Os processos de biotransformação de monoterpenos frequentemente utilizam bactérias do gênero Pseudomonas como biocatalisadores por se adaptarem facilmente a diferentes substratos e condições extremas devido a sua elevada versatilidade metabólica e sistema enzimático complexo. Assim, o presente trabalho visou a utilização de monoterpenos (limoneno, a-pineno e citronelol) como substratos em processos de biotransformação por micro-organismos do gênero Pseudomonas. O Capítulo 1 apresenta um artigo de revisão atualizado sobre o potencial biotecnológico de micro-organismos do gênero Pseudomonas como biocatalisadores em processos de biotransformação. O Capítulo 2 refere-se aos resultados obtidos pelos experimentos que contemplam o isolamento de bactérias em meio seletivo e diferencial para Pseudomonas, e sua aplicação em processos de biotransformação de monoterpenos (R-(+)-limoneno, a-pineno, citronelol). Das 34 linhagens selecionadas, 9 bactérias foram capazes de biotransformar pelo menos um dos substratos em compostos de aroma de maior valor agregado. R-(+)-limoneno foi convertido a cis- e trans-carveol e carvona por 7 linhagens, atingindo concentrações de até 412 mg/L, 275 mg/L e 209 mg/L, respectivamente. a-Pineno, por sua vez, foi usado como fonte de carbono e energia por 7 linhagens e foi convertido principalmente em cis-verbenol e verbenona a baixas concentrações por 5 linhagens. Outros compostos como limoneno, mirtenol e ß-pineno, também foram identificados como produtos principais da conversão do a-pineno por 2 linhagens. Por outro lado, apenas 3 linhagens foram capazes de metabolizar citronelol em outros compostos derivados, como óxidos de rosa e isopulegol. O efeito da variação do pH do meio de biotransformação e da indução das linhagens, através da pré-exposição do micro-organismo ao substrato, no crescimento celular e formação de produtos de bioconversão foram avaliados com o intuito de otimizar o processo de biotransformação. A produção de óxido de rosa a partir de citronelol foi estudada e detalhada no capítulo final, que configurou um artigo publicado na revista Chemical Engineering Transactions. Em testes de citotoxicidade, a linhagem mostrou alta resistência a maiores concentrações de terpeno, revelando grande potencial para posterior otimização do processo. Os compostos derivados mais notáveis foram destacados no presente trabalho pela alta qualidade sensorial e alto valor agregado. Além das notas sensoriais altamente relevantes industrialmente, a carvona e o carveol são ainda reconhecidos por apresentar algumas funções biológicas. A verbenona e verbenol se destacam pelo alto custo e vasta aplicação nas áreas alimentícia, da agricultura, e da medicina. O óxido de rosa é um dos componentes mais importantes na criação de composições florais em perfumaria, além de possuir um baixo threshold. Sendo assim, a biotransformação de precursores de baixo custo em compostos de alto valor agregado pode ser considerado uma estratégia vantajosa e econômica Abstract: Aroma compounds influence greatly the flavor of food products and govern their acceptance by consumers and market success. The increasing consumer preference for natural products has encouraged remarkable efforts towards the development of biotechnological processes for the production of natural flavor compounds. Biotransformation of terpenes represents a very promising alternative for production of aromas, since overcome the problems associated with chemical synthesis such as the low generation of toxic waste and high regio-and stereo-selectivity reactions. In addition, products obtained by microbiological methods can be labeled 'natural' under Brazilian law (ANVISA Resolution No. 104 dated May 14, 1999). Studies on monoterpene bioconversion frequently use bacteria from the genus Pseudomonas as biocatalysts since they adapt easily to different substracts and extreme conditions thanks to their high metabolic versatility and complex enzyme system. Therefore, the present work aims to use monoterpenes, such as limonene, a-pinene and citronellol, as substrate for the biotransformation processes by microorganisms from the genus Pseudomonas. The Chapter 1 presents a current review on the biotechnological potencial of microorganisms from the genus Pseudomonas. Chapter 2 refers to the results obtained from laboratory experiments which include the isolation of bacteria in selective and differential medium for Pseudomonas and their application in monoterpene biotransformation processes ((R-(+)-limonene, a-pinene, citronellol). Among 32 selected strains for investigation of biotransformation capability, 9 bacteria were able to biotransform one of the substrates on value-added flavor compounds. R-(+)-limonene was converted to cis- and trans-carveol and carvone by 7 strains, at concentrations of 412 mg/L, 275 mg/L e 209 mg/L, respectively. a-Pinene, in turn, was used as sole carbon and energy source for 7 strains, and yielded especially cis-verbenol and verbenone at low concentrations by 5 strains. Other compounds such as limonene, myrtenol and ß-pinene have also been identified as major products from the conversion of a-pinene by 2 strains. On the other hand, only 3 strains were able to metabolize citronelol on other derivative compounds, such as rose oxides and isopulegol. The effects of different pHof biotransformation medium and induction phase on cell growth and product concentration were evaluated in order to optimize the biotransformation process. The production of rose oxides by strain L1B2P was studied and detailed separately in the third chapter, set as a published article at Chemical Engineering Transactions. In citotoxicity tests, the strain showed impressive terpene resistance, revealing great potential for further process optimization. Most notable compound derivatives were highlighted in the present work due to their high sensory quality and added value. Besides highly industrially relevant sensory notes, carvone and carveol are also recognized by pursuing some biological functions. The verbenone and verbenol stand by the high cost and wide application in food, agriculture, and medicine fields. Rose oxide, in turn, is one of the most important components in creating floral compositions in perfumery, besides its low threshold. Thus, biotransformation of inexpensive precursors into high value added compounds can be considered an economical and advantageous strategy Mestrado Ciência de Alimentos Mestra em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

44

Abrahão, Meissa Rocha Essenfelder 1984. "Desenvolvimento de processo biotecnológico para produção de compostos de aroma por fungos endofíticos : Biotechnological process development for the production of aroma compounds through endophytic fungi." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254210.

Testo completo

Abstract (sommario):

Orientador: Gláucia Maria Pastore Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-08-24T20:06:37Z (GMT). No. of bitstreams: 1 Abrahao_MeissaRochaEssenfelder_M.pdf: 2164946 bytes, checksum: 5d4f141c4a784953c0b6ee598b74b6e3 (MD5) Previous issue date: 2014 Resumo: A biotecnologia é uma área interdisciplinar que tem possibilitado inúmeros avanços no desenvolvimento de processos sustentáveis e na obtenção de novos produtos de interesse industrial. Entre estes exemplos estão os aromas naturais que, atualmente, são preferidos por muitos consumidores e já dominam o mercado em certas regiões como a Europa. Uma das opções biotecnológicas para a obtenção destes compostos ocorre pela biotransformação de terpenos, que são derivados de isoprenos, e substratos amplamente distribuídos na natureza. Estes compostos são classe relevante dentre os compostos de aroma e alguns podem ser obtidos a custos relativamente baixos. Limoneno e ?-pineno, por exemplo, estão disponíveis como subprodutos de indústrias de frutas cítricas e de papel, respectivamente. Estes monoterpenos são considerados substratos ideais para obtenção de derivados oxigenados, os terpenóides, muitos dos quais de grande interesse comercial. Nessa perspectiva, 51 fungos endofíticos das frutas caju (Anacardium occidentale L.), jenipapo (Genipa americana L.), sapoti (Manilkara zapota L.) e camu-camu (Myrciaria dubia), foram isolados durante este trabalho. As linhagens foram também avaliadas quanto ao potencial para biotransformação de limoneno ou ?-pineno como fontes únicas de carbono. A partir deste segundo substrato, destacaram-se dois fungos produtores de verbenona, um dos compostos chave do aroma de alecrim (Rosmarinus officinalis). A produção de verbenona por via biotecnológica mostrou um grande potencial para a continuidade dos estudos, tendo em vista que a concentração obtida foi de, aproximadamente, 200 mg/L após 288 horas de contato com o subtrato ?-pineno. Além disso, outro fungo apresentou produção de álcool perílico a partir da biotransformação de limoneno. Este produto é um terpenóide, cujos mecanismos de proteção contra o câncer já tem sido investigados e reconhecidos, aumentando o interesse na sua pesquisa e produção biotecnológica. No encerramento do trabalho, os três fungos com resultados positivos pra biotransformação de terpenos foram analisados em microscopia óptica para observação de suas morfologias e auxílio na identificação Abstract: As an interdisciplinary field, biotechnology has allowed several advances for the development of sustainable processes and many achievements concerning production of new compounds with industrial interest. Natural aroma compounds have been frequently prioritized by costumers and dominate a considerable market share in some regions such as Europe, and one of biotechnological routes for obtaining these compounds occurs through the biotransformation of terpenes. These substrates are naturally available compounds derived from isoprene units, and represent a relevant class of aroma compounds, which can be often obtained at relatively low costs. Limonene and ?-pinene, for instance, are available as by-products in citrus and pine industries, respectively. These monoterpenes represent ideal precursors for biotechnological production, leading to their oxygenated derivatives denominated terpenoids, some of which commercially valuable. In this perspective, fifty one endophytic fungi from Brazilian fruits, such as cashew (Anacardium occidentale L.), genipap (Genipa americana L.), sapodilla (Manilkara zapota L.) and camu-camu (Myrciaria dubia) were screened during this work. Furthermore, these fungal strains were tested in the biotransformation of limonene or ?-pinene as sole carbon source. Amongst all fungi, two strains showed noteworthy capability to biotransform ?-pinene into verbenone, key compound of rosemary (Rosmarinus officinalis) aroma. The biotechnological production of verbenone proved to be an interesting strategy with a great future potential, considering that that the concentration of this product reached approximately 200 mg/L after 288 hours of contact with the substrate ?-pinene. Moreover, from the biotransformation of limonene, one fungi produced perillyl alcohol. This important terpenoid presents protection mechanisms against cancer already investigated and recognized. The practical steps achieved in this project also involved the observation of these strains with positive results through optical microscopy, in order to verify their morphology and general characteristics Mestrado Ciência de Alimentos Mestra em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

45

Carey, Michelle. "Interaction of aromas with starch/emulsion systems." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268505.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

46

Cook, David J. "The effects of viscosity on flavour perception." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289066.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

47

Costa, Argentina Sampaio. "Contribuição para o estudo da linhagem Neurospora sp isolada de beiju de mandioca." [s.n.], 1995. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255848.

Testo completo

Abstract (sommario):

Orientador: Yong Kun Park Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Made available in DSpace on 2018-07-20T18:48:13Z (GMT). No. of bitstreams: 1 Costa_ArgentinaSampaio_M.pdf: 3093349 bytes, checksum: 64f6124b9112499d133b16095d667efc (MD5) Previous issue date: 1995 Resumo: Foram isoladas diversas linhagens de Neurospora sp de amostras de beijus provenientes de vários locais do Estado do Maranhão produtores de tiquira, bebida alcoólica típica da região. Em todas as linhagens, inclusive N. sitophila ATCC 46892 obtida do beiju por Park et alii em 1982 foi verificada a capacidade de produzir o composto identificado como etil hexanoato, responsável pelo forte aroma de frutas. Neste trabalho foram realizados estudos comparativos das características bioquímicas e microbiológicas entre Neurospora de beiju e outras linhagens de Neurospora, tais como N. sitophila NRRL 2884, N. tetrasperma NRRL 2164, N. intermedia NRRL 5506 e N. crassa NRRL 2223. Verificou-se que apenas as linhagens de Neurospora isoladas de beiju produziram o aroma de frutas. Estas linhagens apresentaram maior capacidade fermentativa em amido 5% e maior atividade amiloglicosidásica que as linhagens de N. tetrasperma 2164, N. intermedia 5506 e N. crassa 2223 da coleção de cultura NRRL, porém menor que a linhagem N. sitophila NRRL 2884. Quanto à atividade das enzimas xilanase, pectinase, CMCase e lipase as linhagens de Neurospora apresentaram resultados negativos. Através de análises quimiotaxonômicas foi identificada a Coenzima Q-I0 em todas as linhagens. Observou-se diferenças no tamanho e coloração de conídias de Neurospora isoladas de beiju e Neurospora da coleção NRRL. Verificou-se o cruzamento pelo aparecimento de peritécios resultante da fertilização apenas entre N. sitophila NRRL 2884 e Neurospora isoladas de beiju. Concluiu-se que as linhagens de Neurospora isoladas de beiju e N. sitophila NRRL 2884 são da mesma espécie, porém apresentam características bioquímicas e microbiológicas diferentes Abstract: Several strains of Neurospora sp were isolated from beiju which is used for production of tiquira in various regions of the state of Maranhão. All isolated strains, including Nelfrospora sitophila ATCC 46892 wich was also isolated from beiju by Park et alii in 1982 have produced fruity aroma that was identified as ethy hexanoate. In this research was studied biochemical and morfological characteristics of all strains of Neurospora sp such as Neurospora sitophila NRRL 2884, N. tetrasperma NRRL 2164, N. intermedia NRRL 5506 and N. crassa NRRL 2223. It was found that these strains of Neurospora sp from beiju have produced the fruity aroma where as other strains of Neurospora sp did not. All strains of Neurospora from beiju pro.duced less amyloglucosidase and alcohol by fermentation than Neurospora sitophila NRRL 2884, but produced more than other strains of Neurospora sp. It was also found that all strains of Neurospora did not produced xylanase, pectinase, carboxymethylcellulase and lipase. It was found that all strains of Neurospora have ubiquinone Q-I0. Strains of Neurospora sp from beiju showed conidiation and pigmentation differents of strains of Neurospora NRRL. It was examined crossing only between strains of Neurospora from beiju and N. sitophila NRRL 2884. It was concluded that the strains of Neurospora sp isolated from beiju and N. sitophila NRRL 2884 are kind level, however have different biochemical and morfological characteristics Mestrado Mestre em Ciência de Alimentos

Gli stili APA, Harvard, Vancouver, ISO e altri

48

Tisma, Eddie, and Johan Nilsson. "Development of Web portal for health centre Aroma in Vetlanda." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Data- och elektroteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-16318.

Testo completo

Abstract (sommario):

This exam paper has been made with the health care center Aroma in Vetlanda. The work was to deliver a complete web portal with an integrated booking system. The objectives were to provide a complete informative website for Aromas users with the option to make an appointment for a vaccination or health certificate, order prescriptions and get update information directly published by Aromas staff. And to give the staff of Aroma a graphical Web interface to manage the content and the booking system.The report goes through the basic language used and why. Further it takes up it how works and how the final product looks and behaves. Detta examensarbete har gjorts med Vårdcentralen Aroma i Vetlanda. Arbetet gick ut på att leverera en komplett webbportal med integrerat bokningssystem. Målen var att kunna leverera en informativ webbplats för Aromas användare med möjlighet att boka tid vaccinationer och intyg, beställa recept och ta del av nyheter direkt publicerade av deras personal. Samt att ge personalen ett grafiskt webbgränssnitt för att hantera allt innehåll och bokningssystemet. Rapporten går grundläggande igenom vilka språk som använts och varför. Vidare redogörs hur arbetet har utförts och hur den slutliga produkten ser ut och fungerar.

Gli stili APA, Harvard, Vancouver, ISO e altri

49

Harsch, Michael Johannes. "Identification of yeast genes involved in sauvignon blanc aroma development." Thesis, University of Auckland, 2009. http://hdl.handle.net/2292/5293.

Testo completo

Abstract (sommario):

The grape variety Sauvignon Blanc (SB) is the flagship of New Zealand’s wine industry and accounted for over 75 % of the value of total wine exports in 2008. Two volatile thiols, 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl-acetate (3MHA), reminiscent of grapefruit and passion fruit respectively, are critical for the main varietal characters in New Zealand SB. These aromatic thiols are not present in the grape juice, but are synthesized and released by the yeast during alcoholic fermentation from non-aromatic precursors. The aim of this work was to elucidate the underlying genetics of volatile thiol synthesis in yeast (Saccharomyces cerevisiae) during alcoholic fermentation of grape juice. A gene-deletion strategy was chosen for the investigation of putative genes influencing 3MH and 3MHA release. The first part of this thesis optimized fermentation conditions in grape-juice-based media, which enabled auxotrophic laboratory strains, derived from S288C, to ferment grape juice to completion with high efficiency. Key steps to achieving this goal were the supplementation of the grape juice with higher than recommended amounts of amino acids, which increased the fermentation rate of auxotrophic yeast strains. Lysine auxotrophic strains especially benefited from this measure. In combination with the dilution of SB grape juice by 25 % with synthetic grape juice without sugars, the auxotrophic laboratory yeast BY4743 was able to metabolize all sugars in the grape juice-based media in a time frame similar to that of a commercial wine yeast. The key properties of the resulting wine were comparable to wine made with a commercial wine yeast under the same conditions. In the second part, these newly developed fermentation conditions were employed to screen 69 single-gene deletion strains in the laboratory yeast background BY4743. The list of the 69 candidate genes was compiled by combining existing knowledge about thiol production in yeast with the mining of several biological databases. Screening of the single-gene deletions revealed 17 genes which caused biologically relevant increases or decreases in volatile thiol production, but none abolished it. The majority of the 17 genes were related to the sulfur and nitrogen metabolism in yeast. A subset of these thiol-influencing genes were also deleted in a wine yeast, and were overexpressed in both wine yeast and laboratory yeast, to gain more insight in their regulatory effects. The findings confirmed that sulfur and nitrogen metabolism in yeast were important in regulating 3MH and 3MHA synthesis. Different sulfur and nitrogen sources were added to the grape must prior to fermentation and their effect on thiol release was studied. It was found that nitrogen sources urea and DAP, as well as, the sulfur compound S-ethyl-L-cysteine (SEC) increased 3MH and 3MHA concentrations in the resulting wines. The addition of cysteine to grape juice fermented with wine yeast deleted in genes CYS3 and CYS4 more than doubled total thiol production. Mapping approaches to investigate thiol production in yeast were employed in the final part of this thesis. Genetically mapped F2 progeny of a cross between a low thiol-producing yeast strain and a high-thiol producer were screened for their thiol phenotype. The 3MH and 3MHA phenotypes across 48 screened F2 progeny resembled normal distributions, indicating a quantitative trait. Subsequent mapping identified a locus on chromosome 14 with a small effect on the 3MHA phenotype, but no obvious candidate genes were evident in the region. Another approach to investigate the evolution of volatile thiols in yeast included the use of SEC, a thiol compound resembling the cysteinylated precursor of 3MH, as a sole nitrogen source in a yeast growth assay. It was found that most wine yeast, European yeast isolates and laboratory yeasts could utilize SEC as a nitrogen source, whereas various other S. cerevisiae isolates could not. Crosses between three pairs of Sec- and Sec+ yeast strains strongly indicated that this trait was monogenically inherited. However, no direct correlation between the SEC phenotype and volatile release could be observed. Genetic mapping experiments in one SEC-segregating yeast population linked this SEC phenotype to the leu2-D0 deletion in a cross between a Leu+ and Leu- yeast strain. It was shown that leucine auxotrophy most likely caused the Sec- phenotype. In a second F2 population of a cross between prototrophic Sec+ and Sec- strains, strong linkage was established to a region on chromosome 6 containing two candidate genes, DUG1 and IRC7. DUG1 was proved not to be the cause of the SEC phenotype, whereas IRC7 remains a strong candidate gene.

Gli stili APA, Harvard, Vancouver, ISO e altri

50

Deng, Zhiping. "Acoustic wave sensors for aroma components using conducting polymer films." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0017/NQ27632.pdf.

Testo completo

Gli stili APA, Harvard, Vancouver, ISO e altri

Tesi sul tema "Aroma"

Cita una fonte nei formati APA, MLA, Chicago, Harvard e in molti altri stili