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Artykuły w czasopismach na temat "Orange juice"
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Kowalska, Małgorzata, Justyna Konopska, Melánia Feszterová, Anna Zbikowska i Barbara Kowalska. "Quality Assessment of Natural Juices and Consumer Preferences in the Range of Citrus Fruit Juices". Applied Sciences 13, nr 2 (5.01.2023): 765. http://dx.doi.org/10.3390/app13020765.
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The purpose of the study was to analyse and update consumers’ changing preferences in the choice of citrus fruit juices and to evaluate the sensory and physicochemical characteristics of two kinds of juices: juice squeezed from raw fruit and a commercial juice indicated by respondents as best matching their preferences. The survey was conducted in the form of an online survey posted on app.ankieteo.pl. The survey was also sent via a link through social networks. A total of 862 people took part in the survey. Consumers are most likely to consume juices one to three times a week (28.3%). Orange juice was the most popular among respondents (52.4%). The main factors influencing decisions to purchase citrus fruit juices are the type of fruit from which the juice was made, the vitamin content and the product’s price. In choosing juices, respondents were also guided by favourable health qualities and the presence of minerals. From the physicochemical determinations of orange juices obtained from a juicer and squeezer and commercial juice “O”, it was found that the quality of commercial orange juice indicated by consumers in the survey is comparable to juices made with a squeezer or a juice.
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Barghouthy, Yazeed, i Bhaskar K. Somani. "Role of Citrus Fruit Juices in Prevention of Kidney Stone Disease (KSD): A Narrative Review". Nutrients 13, nr 11 (17.11.2021): 4117. http://dx.doi.org/10.3390/nu13114117.
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To explore the relationship between citrus fruit juices (oranges, grapefruits, and lemonades) and kidney stone disease (KSD). Methods: A systematic review was performed using the Medline, EMBASE, and Scopus databases, in concordance with the PRISMA checklist for all English, French, and Spanish language studies regarding the consumption of citrus fruit juices and the relationship to urinary stone disease. The main outcome of interest was the association of citrus fruit juices with KSD. Results: Thirteen articles met the criteria for inclusion in the final review. Three large epidemiological studies found that grapefruit juice was a risk factor for stone formation, while orange juice did not increase the risk for KSD. Ten small prospective clinical studies found that orange, grapefruit, and lemon juices all increased urinary citrate levels. Only orange and grapefruit juices had an alkalinizing effect and while lemon juice has a protective effect by raising urinary citrate levels, it lacked a significant alkalinizing effect on urine pH. Orange juice and grapefruit juices significantly increased urinary oxalate levels, while orange juice also had a high carbohydrate content. Conclusion: While orange juice seems to play a protective role against stone formation, grapefruit was found to raise the risk of KSD in epidemiological studies but had a protective role in smaller clinical studies. Lemon juice had a smaller protective role than orange juice. Larger amounts of, as well as more accurate, data is needed before recommendations can be made and a high carbohydrate content in these juices needs to be taken into consideration.
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Purkiewicz, Aleksandra, Joanna Ciborska, Małgorzata Tańska, Agnieszka Narwojsz, Małgorzata Starowicz, Katarzyna E. Przybyłowicz i Tomasz Sawicki. "The Impact of the Method Extraction and Different Carrot Variety on the Carotenoid Profile, Total Phenolic Content and Antioxidant Properties of Juices". Plants 9, nr 12 (11.12.2020): 1759. http://dx.doi.org/10.3390/plants9121759.
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The study assesses the antioxidant activity (AA), carotenoid profile and total phenolic content (TPC) of carrot juices obtained from three different varieties (black, orange and yellow) and prepared using high- (HSJ) and low-speed juicer (LSJ). The AA assessment was carried out using four assays (DPPH, ABTS, PCL ACW and PCL ACL). The content of carotenoids was conducted by high performance liquid chromatography equipped with a diode array detector (HPLC-DAD) method, while the total phenolic content by the spectrophotometric method. It was shown that orange carrot juices contain more carotenoids than yellow and black carrot juices, approximately ten and three times more, respectively. The total carotenoid content in orange carrot juice made by the HSJ was higher (by over 11%) compared to juice prepared by the LSJ. The highest total phenolic content was noticed in black carrot juices, while the lowest in orange carrot juices. In black carrot juices, a higher range of TPC was found in juices made by HSJ, while in the case of the orange and yellow carrots, the highest content of TPC was detected in juices prepared by the LSJ. AA of the juices was highly dependent on the carrot variety, juice extraction method. The most assays confirmed the highest AA values in black carrot juices. Furthermore, it was shown that the HSJ method is more preferred to obtain orange and yellow carrot juices with higher antioxidant properties, while the LSJ method is more suitable for black carrot juice extraction.
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Colás-Medà, Pilar, Iolanda Nicolau-Lapeña, Inmaculada Viñas, Isma Neggazi i Isabel Alegre. "Bacterial Spore Inactivation in Orange Juice and Orange Peel by Ultraviolet-C Light". Foods 10, nr 4 (15.04.2021): 855. http://dx.doi.org/10.3390/foods10040855.
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Spore-forming bacteria are a great concern for fruit juice processors as they can resist the thermal pasteurization and the high hydrostatic pressure treatments that fruit juices receive during their processing, thus reducing their microbiological quality and safety. In this context, our objective was to evaluate the efficacy of Ultraviolet-C (UV-C) light at 254 nm on reducing bacterial spores of Alicyclobacillus acidoterrestris, Bacillus coagulans and Bacillus cereus at two stages of orange juice production. To simulate fruit disinfection before processing, the orange peel was artificially inoculated with each of the bacterial spores and submitted to UV-C light (97.8–100.1 W/m2) with treatment times between 3 s and 10 min. The obtained product, the orange juice, was also tested by exposing the artificially inoculated juice to UV-C light (100.9–107.9 W/m2) between 5 and 60 min. A three-minute treatment (18.0 kJ/m2) reduced spore numbers on orange peel around 2 log units, while more than 45 min (278.8 kJ/m2) were needed to achieve the same reduction in orange juice for all evaluated bacterial spores. As raw fruits are the main source of bacterial spores in fruit juices, reducing bacterial spores on fruit peels could help fruit juice processors to enhance the microbiological quality and safety of fruit juices.
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Zvaigzne, Gaļina, Daina Kārkliņa, Joerg-Thomas Moersel, Sasha Kuehn, Inta Krasnova i Dalija Segliņa. "Ultra-High Temperature Effect on Bioactive Compounds and Sensory Attributes of Orange Juice Compared with Traditional Processing". Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 71, nr 6 (1.12.2017): 486–91. http://dx.doi.org/10.1515/prolas-2017-0084.
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Abstract Orange juices are an important source of bioactive compounds. Because of its unique combination of sensory attributes and nutritional value, orange juice is the world’s most popular fruit juice. Orange (Citrus sinensis) juice of Greek Navel variety was used in this study. The impact of Conventional Thermal Pasteurisation (94 °C/30') (CTP) and alternative Ultra-High Temperature (UHT) (130 °C/2') processing on bioactive compounds and antioxidant capacity changes of fresh Navel orange juice was investigated. Sensory attributes of processed juices were evaluated. Results showed that using technologies CTP and UHT orange juice Navel significantly changed vitamin C concentration in comparison with fresh orange juice. The highest concentration of antioxidants (vitamin C, total phenols, hesperidin and carotenoids) was observed in orange juice Navel produced by UHT technology. Sensory results indicated that characteristics of the orange juice obtained using UHT technology were more liked than the CTP heat treated juice. UHT technology emerges as an advantageous alternative process to preserve bioactive compounds in orange juice.
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HANKIN, LESTER, i HARRY M. PYLYPIW. "Pesticides in Orange Juice Sold in Connecticut". Journal of Food Protection 54, nr 4 (1.04.1991): 310–11. http://dx.doi.org/10.4315/0362-028x-54.4.310.
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There is concern that orange juice from foreign countries may contain residues of pesticides not allowed in the United States. Of 17 orange juices examined, 15 listed Brazil as the source of all or part of the juice used. Six samples contained residues. All pesticides found were allowed for use in the United States, and all residues were well below EPA allowable tolerances in oranges.
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Zacarías-Garcia, Jaime, Guiselle Carlos, José-Vicente Gil, José Luís Navarro, Lorenzo Zacarías i María-Jesús Rodrigo. "Juices and By-Products of Red-Fleshed Sweet Oranges: Assessment of Bioactive and Nutritional Compounds". Foods 12, nr 2 (14.01.2023): 400. http://dx.doi.org/10.3390/foods12020400.
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The content of nutrients and bioactive compounds, and antioxidant capacity were assessed in the juices from two red-fleshed oranges, Cara Cara and Kirkwood, and compared with that of a standard Navel orange. Two juice extraction procedures, hand-squeezing and industrial, and two treatments, pasteurization (85 °C/30 s) and high-pressure homogenization (HPH, 150 MPa/55 °C/1 min), were evaluated. For most of the nutrients and bioactive compounds, the hand and industrial juice squeezing rendered similar extraction efficiency. Individual composition of carotenoids in the juices were differentially affected by the extraction procedure and the treatments, but the red-fleshed orange juices contained between 3- to 6-times higher total carotenoids than the standard Navel juices, being phytoene and phytofluene the main carotenoids. The industrial and treated juices of both red-fleshed oranges contained 20–30% higher amounts of tocopherols but about 20% lower levels of vitamin C than Navel juices. Navel juices exhibited higher hydrophilic antioxidant capacity, while the red-fleshed orange juices showed an improved lipophilic antioxidant capacity. The main distinctive characteristic of the industrial juice by-product of the red-fleshed oranges was a higher content of carotenoids (×10) and singlet oxygen antioxidant capacity (×1.5–2) than the Navel by-product.
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Zhou, Qi, Guijie Li, Zhu Ou-Yang, Xin Yi, Linhua Huang i Hua Wang. "Volatile Organic Compounds Profiles to Determine Authenticity of Sweet Orange Juice Using Head Space Gas Chromatography Coupled with Multivariate Analysis". Foods 9, nr 4 (16.04.2020): 505. http://dx.doi.org/10.3390/foods9040505.
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An efficient and practical method for identifying mandarin juice over-blended into not from concentrate (NFC) orange juice was established. Juices were extracted from different cultivars of sweet orange and mandarin fruits. After being pasteurized, the volatile organic compounds (VOCs) in the juice samples were extracted using headspace solid-phase microextraction, and qualitatively and quantitatively analyzed using gas chromatography–mass spectrometry detection. Thirty-two VOCs contained in both the sweet orange juice and mandarin juice were used as variables, and the identification model for discriminating between the two varieties of juice was established by principal component analysis. Validation was applied by using common mandarin juices from Ponkan, Satsuma and Nanfengmiju cultivars blended at series of proportions into orange juices from Long-leaf, Olinda, and Hamlin cultivars. The model can visually identify a blending of mandarin juice at the volume fraction of 10% or above.
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Adekunle, Ezekiel, James Daramola, Olusiji Sowande, John Abiona i Monsuru Abioja. "Effects of apple and orange juices on quality of refrigerated goat semen". Journal of Agricultural Sciences, Belgrade 63, nr 1 (2018): 53–65. http://dx.doi.org/10.2298/jas1801053a.
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This study investigated the effects of apple and orange juices on quality of refrigerated spermatozoa of goat bucks. Semen samples from WAD goat bucks were diluted with Tris-egg yolk extenders each supplemented with apple and orange juices at 0, 2.5, 5, 7.5 and 10/100 ml of diluents. The diluted semen samples were assessed for sperm viability and malondialdehyde (MDA) concentration after in vitro storage for 240 hours at 5oC. The ability to maintain sperm motility was higher in the extenders with 7.5% orange juice followed by 10% apple juice compared to other treatments (P<0.05). The extenders supplemented with 2.5%, 5% and 7.5% apple juice, and 5% orange juice had higher intact acrosome compared to other treatments and the control (P<0.05). The 10% orange juice had higher percentage membrane integrity compared to other treatments. Consistent and reduced (P<0.05) MDA levels were observed in the extenders supplemented with fruit juices and lower MDA was observed in the extenders supplemented with 10% apple juice compared to other treatments and the control (P<0.05). The findings reveal that additions of the fruit juices to semen extenders to maintain the viability of refrigerated spermatozoa were best at concentrations of 10 ml/100 ml of apple juice and 7.5 ml/100 ml of orange juice.
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Milani, Thiago Elias, i Avacir Casanova Andrello. "Fresh and pasteurized orange juice analysis by TXRF". Semina: Ciências Exatas e Tecnológicas 42, nr 2 (2.12.2021): 221. http://dx.doi.org/10.5433/1679-0375.2021v42n2p221.
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Orange is considered the main product of the Brazilian citrus agro-industrial complex. However, in the end of 2016, the ANVISA pointed out orange as a risky product due to contamination using pesticides in its cultivation. Therefore, in this context, an analysis of the chemical elements present in fresh and pasteurized orange juices becomes extremely relevant. Thus, this work aims to quantify the elements that are present in fresh and pasteurized orange juices, using the TXRF technique. Samples of fresh orange juice of Pêra variety were acquired in a store in the city of Londrina-PR, were analysed; three samples of oranges were purchased at a store in Itápolis, São Paulo and five more samples of Pêra orange were obtained in the rural area. Samples of pesticides used in orange cultivation were quantified, and three different trademarks of pasteurized juice were analysed. In some of the samples that were collected in Itápolis-SP market, lead (Pb) element was quantified, however its concentration was within the limit established by Brazilian legislation. The aluminium (Al) element was detected in all samples of pasteurized orange juice, showing the influence of the packaging on the elemental concentration of the juice. All pesticides quantified in this work showed a significant concentration of some micro-contaminants, but when the pesticide was diluted in deionized water, those micro-contaminants could not be quantified.
Rozprawy doktorskie na temat "Orange juice"
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Lagacé, Marylène. "The effect of different storage conditions on the quality of orange juice /". Thesis, McGill University, 1998. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20831.
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Unpasteurized (condition A) and pasteurized (condition B) orange juice samples were stored frozen for eight months. In addition, pasteurized samples were also aseptically packaged and stored at +1°C in polyethylene bags (condition C). Nine quality parameters were monitored during the eight months of storage: sedimentation of the pulp, cloud measurement, aroma volatiles, ascorbic acid concentration, viscosity, density, colour, sugar content (sucrose, glucose and fructose), organic acids (malic and citric), in addition to sensory analysis. The optimum storage condition for freshly processed orange juice was the unpasteurized frozen storage method (condition A). The juice retained most of its chemical and physical properties and was rated by a sensory panel to have the highest sensory score.
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Li, Zhuo 1958. "Studies on the storage of orange juice". Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63766.
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Garcia-Wass, Febe. "Orange juice authenticity using pyrolysis mass spectrometry". Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312084.
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Basak, Sarmistha. "Studies on high pressure processing of orange juice : enzyme inactivation, microbial destruction, and quality changes, process verification and storage". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36874.
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High pressure (HP) processing has been emerging rapidly as a novel technique for non-thermal preservation of foods. Application of HP processing for shelf life extension of orange juice was the principal objective of the current research. To accomplish this objective, and to establish a scientific basis for HP processing of orange juice, a systemic approach was used which included the evaluation of: (a) HP inactivation kinetics of pectin methyl esterase (PME, the key enzyme in orange juice implicated with respect to quality changes), (b) destruction of spoilage microorganisms and changes in product quality, (c) HP process verification and finally, (d) storage studies on HP treated orange juice.In preliminary studies, the effect of HP treatment on indigenous microorganisms, texture and color of selected fresh fruits and vegetables were evaluated. Results showed that HP had a significant effect on the destruction of microorganisms. Product texture and color were mildly affected, often resembling the appearance of mildly heat-treated products.
Pressure induced inactivation kinetics of pectin methyl esterase (PME) was investigated at pH 3.7 and 3.2 in freshly squeezed single strength (12.6°Brix) and concentrated (10--40° Brix) orange juice. Results showed a biphasic nature of pressure induced inactivation of PME in both juices. The first phase consisted of rapid change in inactivation of enzyme, designated as instantaneous pressure kill (IPK), due to pulse pressurization, followed by gradual inactivation of enzyme, characterized by a first order rate of inactivation during pressure hold-time.
Combination treatment involving pressure cycle, pressure level and pressure hold-time was then evaluated for inactivation of PME using a response surface methodology. Overall, pressure pulse had a lower effect on inactivation of PME compared to other factors.
Pressure destruction kinetics of Leuconostoc mesenteroides and Saccharomyces cerevisiae the spoilage organisms in orange juice, were then investigated. Pressure destruction kinetics followed the same dual effect behavior, as observed with PME inactivation. IPK effect increased with pressure cycles and was more pronounced with S. cerevisiae that Leu. mesenteroides.
Storage studies of HP treated single strength and concentrated orange juice were conducted at selected temperatures (4, 10 and 20°C). Results showed that treated juice was microbiologically stable from a few days to several weeks depending on type of juice, storage temperature and processing conditions. (Abstract shortened by UMI.)
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Almeida, Francisca Diva Lima. "Employment of emerging technologies on orange juice processing added of prebiotic fructo-oligosaccharide and orange juice produced via enzymatic synthesis". Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16471.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorConselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
The aim of this research was to use emerging technologies on the processing of the prebiotic orange juice added of fructo-oligosaccharides (FOS) and in prebiotic orange juice produced by enzymatic synthesis. The first stage of the study was evaluated the effect of atmospheric pressure cold plasma (ACP) and high pressure processing (HPP) on the prebiotic orange juice added 7% commercial FOS. The orange juice was directly and indirectly exposed to plasma discharge at 70 kV with processing times of 15, 30, 45 and 60 seconds. For high pressure processing, the juice containing the same concentration of FOS was treated at 450 bars for 5 minutes. After the treatments, the fructo-oligosaccharides were qualified and quantified by Thin Layer Chromatography (TLC), using densitometer. The organic acids, color analysis and pH values were also evaluated. Both processes did not degrade the FOS. The organic acids and the color of the treated samples were also preserved. On the second stage of the study, the effect of plasma and ozone treatments on prebiotic orange juice produced by enzymatic synthesis were evaluated. The orange juice was directly and indirectly exposed to plasma discharge at 70 kV with processing times of 15, 30, 45 and 60 seconds. For ozone processing, different loads (0.057, 0.128 and 0.230 mg/ O3.mL of juice) were evaluated. After the treatments, the oligosaccharides were quantified by HPLC. The juice pH, color, total phenolic content and total antioxidant activity were also determined. Both processes promoted a partial degradation of the oligosaccharides in the juice. However, the juice maintained an enough amount of oligosaccharides to be classified as a prebiotic food. The other parameters analyzed were preserved. Thus, atmospheric cold plasma and ozone are suitable non-thermal alternatives for prebiotic orange juice treatment.
O objetivo desta pesquisa foi empregar tecnologias emergentes no processamento de suco prebiÃtico de laranja adicionado de fruto-oligossacarÃdeos (FOS) e em suco prebiÃtico de laranja produzido via sÃntese enzimÃtica. A primeira etapa da pesquisa consistiu em avaliar o efeito da aplicaÃÃo das tecnologias de plasma e de alta pressÃo, como mÃtodos de conservaÃÃo, em suco de laranja adicionado de 7% de FOS comercial. O suco foi exposto direta e indiretamente ao processamento por plasma em diferentes tempos: 15 30, 45 e 60 s. Para o processamento com alta pressÃo, o suco foi tratado a uma pressÃo de 450 bars por 5 minutos. ApÃs os tratamentos, a concentraÃÃo de fruto-oligossacarÃdeos foi quantificada pela tÃcnica de cromatografia em camada delgada (CCD), utilizando o equipamento densitÃmetro. DeterminaÃÃes de cor, pH e concentraÃÃo de Ãcidos orgÃnicos foram tambÃm realizadas. Ambos os processos nÃo degradaram os FOS presentes no suco. Ãcidos orgÃnicos e a cor das amostras tratadas tambÃm foram preservados. Na segunda etapa da pesquisa, foi avaliado o efeito da aplicaÃÃo dos tratamentos de plasma e ozÃnio em suco prebiÃtico de laranja produzido via sÃntese enzimÃtica. O suco foi exposto direta e indiretamente ao processamento por plasma, a 70 kV, em diferentes tempos: 15 30, 45 e 60 s. Para o processamento com ozÃnio, diferentes cargas (0,057, 0,128 e 0,230 mg/ O3.mL de suco) foram avaliadas. ApÃs os tratamentos, a concentraÃÃo de oligossacarÃdeos foi determinada pela tÃcnica de HPLC. Os valores de pH, cor, conteÃdo de fenÃlicos totais e atividade antioxidante total tambÃm foram determinados. Ambos os processos promoveram uma degradaÃÃo parcial dos oligossacarÃdeos no suco. Contudo, o suco manteve uma quantidade suficiente de oligossacarÃdeos para ser classificado como um alimento prebiÃtico. Os demais parÃmetros analisados foram preservados. Diante disso, sugere-se que os tratamentos de plasma, alta pressÃo e ozÃnio sÃo alternativas nÃo tÃrmicas adequadas para o tratamento de suco de laranja prebiÃtico.
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Boff, Jeffrey Michael. "Study of volatile compound formation in oxidized lipids and volatile compound retention in processed orange juice". Columbus, OH : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1054660479.
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Thesis (Ph. D.)--Ohio State University, 2003.Title from first page of PDF file. Document formatted into pages; contains xxi., 190 p.: ill. Includes abstract and vita. Advisor: David B. Min, Dept. of Food Science and Nutrition. Includes bibliographical references (p. 179-190).
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Ayhan, Zehra. "Packaging requirements for pulsed electric field processed orange juice /". The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488196781734345.
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Donato, Roberta M. "Globalization and trade relations the US and Brazilian orange juice dispute /". Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1141950268.
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Rintelmann, Anke. "DNA based methods for food authentication". Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272357.
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Vieira, Fabiana Neves. "Effect of pasteurisation and high pressure on orange juice properties". Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10100.
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Mestrado em Bioquímica - Bioquímica AlimentarAs frutas e os produtos derivados de fruta recebem cada vez mais atenção, não só pela sua elevada estabilidade após o processamento através de técnicas tradicionais, mas também devido ao seu elevado conteúdo em compostos bioativos. As características únicas de sabor, aroma e textura são as principais razões da grande aceitação do sumo de laranja, por parte dos consumidores. A utilização de novas técnicas de processamento não térmico para os alimentos tem vindo a aumentar ao longo dos últimos anos. Além disso, a maior procura por produtos microbiologicamente seguros que mantenham as suas características e qualidades originais é a razão mais evidente para o desenvolvimento do processamento por alta pressão como alternativa não térmica. Assim, o principal objetivo deste trabalho foi estudar possíveis benefícios da utilização desta técnica aplicada aos sumos de laranja, comparando esta tecnologia inovadora com o método comumente utilizado no processamento de sumos de laranja, a pasteurização térmica. Foi assim avaliado o efeito da aplicação de tratamento térmico (70°C, 30 seg) e de alta pressão (550 MPa, 70 seg, 18°C) no processamento de sumo de laranja ao longo de 36 dias de armazenamento sobre alguns compostos bioativos, como antocianinas, flavonoides, carotenoides e compostos fenólicos, na atividade antioxidante, cor e sólidos solúveis totais. Observouse que, comparativamente ao tratamento térmico, a alta pressão promove a retenção dos compostos fenólicos como antocianinas e flavonoides, aumentando atividade antioxidante do sumo de laranja. Relativamente à cor verificaram-se alterações bastante importantes podendo estar associadas às grandes perdas no conteúdo total de carotenoides. No que respeita a identificação e quantificação dos compostos fenólicos, foram verificados um ácido orgânico (ácido quínico) e 4 compostos fenólicos (ácido elágico, narirutina, vicenina II, e hesperidina). Observou-se que, à excepção do ácido quínico não ocorrem diferenças significativas ao longo do tempo de armazenamento e entre ambas as técnicas de processamento. No entanto, a sua concentração é alterada verificando-se em alguns casos, diminuição significativas no sumo processado por alta pressão, quando comparado com o sumo tratado termicamente. Dessa forma, este trabalho permitiu verificar que a alta pressão promove efeitos benéficos no sumo de laranja podendo, assim, ser utilizada como alternativa às técnicas de processamento térmicas.
Fruits and fruit products receive more and more attention, not only because its low stability when processed by traditional technologies, as pasteurisation; but also due to its high content of bioactive compounds. The favourable ratio of sugar to acid along with the unique orange flavour, gives orange juice its universal high consumer acceptance. The use of novel nonthermal processing food technologies has emerged during the past few years. Moreover, the increasing demand of safer products that maintain their original qualities is the major driver of high pressure processing (HPP) technique development as an alternative to thermal treatment. So, the principal objective of this work was to study the possible benefits on the utilisation of this technique applied on orange juices, when compared to the most commonly used method, thermal pasteurisation. Thus, it has been verified thermal (70°C, 30 sec) and high pressure (550 MPa, 70 sec, 18°C) processing effects during 36 days of storage regarding some bioactive compounds, such as anthocyanins, flavonoids, carotenoids and phenolics, on antioxidant activity, total soluble solids and colour. Here was observed that, comparing with thermal treatment, HP promotes the retention of phenolic compounds such as anthocyanins and flavonoids, increasing the orange juice antioxidant activity. Regarding the colour of the samples were verified some important changes which might be associated mainly to total content of carotenoids losses. Also the characterization and quantification of phenolics present on orange juice samples allowed the identification of one organic acid (quinic acid) and four phenolic acids (ellagic acid, narirutin, vicenin II and hesperidin). Was observed that with the exception of quinic acid, there are no significant changes within the storage time and type of process. However their concentration it’s changed and in some cases it was observed significant decreases on HPP orange juice when compared with TP samples. Thus, with this work was verified that HPP promotes some beneficial effects on orange juice being a great alternative to thermal processing methods used before for this type of products.
Książki na temat "Orange juice"
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1968-, Chanko Pamela, red. Orange juice. New York: Scholastic, 1998.
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Snyder, Inez. Oranges to orange juice. New York: Children's Press, 2003.
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Dan, McGeehan, red. Orange juice before the store. Mankato, MN: The Child's World, 2012.
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Turning oranges into juice. New York: Cavendish Square Publishing, 2014.
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DeMarin, Layne. Oranges: From fruit to juice. Mankato, Minn: Capstone Press, 2012.
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ill, Lexa-Senning Susan, red. What was it before it was orange juice? Chicago, IL: Child's World, 1985.
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Trumbauer, Lisa. The story of orange juice. Bloomington, Minn: Red Brick Learning, 2005.
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Shi mian: Insomnia, manual and orange juice. Taibei Shi: Jian duan chu ban gu fen you xian gong si, 2002.
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Squeezed: What you don't know about orange juice. New Haven: Yale University Press, 2009.
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Sued, Ronaldo. O desenvolvimento da agroindústria da laranja no Brasil: O impacto das geadas na Flórida e da política econômica governamental. Rio de Janeiro, RJ: Editora da Fundação Getúlio Vargas, 1993.
Znajdź pełny tekst źródłaCzęści książek na temat "Orange juice"
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Johnston, Carol S. "Orange Juice". W Beverages in Nutrition and Health, 79–91. Totowa, NJ: Humana Press, 2004. http://dx.doi.org/10.1007/978-1-59259-415-3_6.
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Neves, Marcos Fava, Vinícius Gustavo Trombin, Frederico Fonseca Lopes, Rafael Kalaki i Patrícia Milan. "Orange flavor". W The orange juice business, 120–28. Wageningen: Wageningen Academic Publishers, 2011. http://dx.doi.org/10.3920/978-90-8686-739-4_33.
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Hartel, Richard W., i AnnaKate Hartel. "Fresh Orange Juice". W Food Bites, 153–54. New York, NY: Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-75845-9_49.
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Neves, Marcos Fava, Vinícius Gustavo Trombin, Frederico Fonseca Lopes, Rafael Kalaki i Patrícia Milan. "Orange juice production". W The orange juice business, 52. Wageningen: Wageningen Academic Publishers, 2011. http://dx.doi.org/10.3920/978-90-8686-739-4_12.
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Reay, Dave. "Climate-Smart Orange Juice". W Climate-Smart Food, 9–19. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-18206-9_2.
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Fry, J., G. G. Martin i M. Lees. "Authentication of orange juice". W Production and Packaging of Non-Carbonated Fruit Juices and Fruit Beverages, 1–52. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-0949-3_1.
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Fry, J., G. G. Martin i M. Lees. "Authentication of orange juice". W Production and Packaging of Non-Carbonated Fruit Juices and Fruit Beverages, 1–52. Boston, MA: Springer US, 1999. http://dx.doi.org/10.1007/978-1-4757-6296-9_1.
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Neves, Marcos Fava, Vinícius Gustavo Trombin, Frederico Fonseca Lopes, Rafael Kalaki i Patrícia Milan. "Cost of orange production". W The orange juice business, 69–76. Wageningen: Wageningen Academic Publishers, 2011. http://dx.doi.org/10.3920/978-90-8686-739-4_19.
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Neves, Marcos Fava, Vinícius Gustavo Trombin, Frederico Fonseca Lopes, Rafael Kalaki i Patrícia Milan. "Orange flavor in Europe". W The orange juice business, 129–30. Wageningen: Wageningen Academic Publishers, 2011. http://dx.doi.org/10.3920/978-90-8686-739-4_34.
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Neves, Marcos Fava, Vinícius Gustavo Trombin, Frederico Fonseca Lopes, Rafael Kalaki i Patrícia Milan. "Evolution of Brazilian orange production". W The orange juice business, 46. Wageningen: Wageningen Academic Publishers, 2011. http://dx.doi.org/10.3920/978-90-8686-739-4_10.
Pełny tekst źródłaStreszczenia konferencji na temat "Orange juice"
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Balaban, Murat, Giovanna Ferrentino, Milena Ramirez, Maria L. Plaza i Thelma Calix. "Review of Dense Phase Carbon Dioxide Application to Citrus Juices". W ASME 2008 Citrus Engineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/cec2008-5407.
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The United States is the second largest citrus producer in the world. Florida and California are the two major producing states. While oranges from California are mainly used for fresh fruit consumption, more than 90% of oranges produced in Florida are processed to juice (FAO 2008). Consumers demand high quality and convenient products with natural flavor and taste, and appreciate the “fresh” perception of minimally processed juices. They also look for safe, natural, and healthy products without additives and preservatives. New processing technologies promise to meet all these demands without compromising food safety. Commercial orange juice is thermally processed to inactivate pectinesterase (PE) and spoilage organisms. Active PE causes clarification of orange juice by cloud loss, which is considered a quality defect (Boff et al. 2003). Thermal processing can be detrimental to the organoleptic and nutritional qualities of the juice (Sloan 1995), so the development of non-thermal technologies (Barbosa-Canovas et al. 1998) is desirable in the citrus juice industry. Dense phase carbon dioxide (DPCD) is a non-thermal technology that can inactivate certain micro-organisms and enzymes at temperatures low enough to avoid the thermal effects of traditional pasteurization. This technology relies on the chemical effect of CO2 on micro-organisms and enzymes. DPCD pasteurization technology is commercially available. Most of the commercialization efforts so far have been from Praxair Inc. (Burr Ridge, IL). Based on technology licensed from the University of Florida (Balaban et al. 1988, 1998), Praxair developed a continuous system which uses the DPCD process as a non-thermal alternative to thermal pasteurization (Connery et al. 2005). This system has been commercialized under the Trade Mark “Better Than Fresh (BTF).” To date, Praxair has constructed four mobile BTF units for processing about 1.5 liters per minute for demonstration purposes. In addition, a commercial scale unit of 150 liters per minute was also constructed (Connery et al. 2005) and tested at an orange juice processing plant in Florida. There are other commercialization efforts. The excellent taste of the juice processed with this new technology was demonstrated in three independent sensory panels that compared juice treated with this system to that of fresh squeezed juice. In all the tests, no difference could be detected. It is important that CO2 is completely saturated in the juice if DPCD is to be successful. Saturation (equilibrium solubility) depends on the pressure, temperature, and composition of the juice. Until recently, the exact amount of CO2 to be used in DPCD processing was unknown since solubility data was unavailable at different pressures, temperatures, and juice compositions, and an excess amount was used. To optimize the use of CO2 in this non-thermal process, new equipment has been developed to measure the solubility of CO2 in liquid systems and juices. The objective of this paper is to present a general review of the applications of DPCD to citrus juices and to introduce the use of new equipment developed at the University of Florida to determine the solubility of CO2 in citrus juices. Paper published with permission.
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Puglia, Joseph A., i Douglas P. Harper. "Deoiling Single-Strength Orange Juice". W ASME 1996 Citrus Engineering Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/cec1996-4203.
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Deoiling single-strength orange juice extracted from FMC extractors utilizing a centrifugal separator has traditionally been a difficult task. New technology utilizing hermetic separators has proven very successful for this application. Processors are able to use maximum yield recovery settings in the extractors and hold the separator accountable for reducing the oil content and defects in the juice to acceptable levels. With the demand for Not-From-Concentrate premium orange juice rapidly increasing in the United States, the processor must be able to recover as much juice from the fruit as they can. During certain periods of the production season, the oil in the juice exceeds the USDA grade standards of 0.035%. In order to maintain this high quality juice throughout the processing season, the demand for new technology in oil reduction was required. New technology, utilizing hermetic separators for deoiling, has lead to significant gains in juice yields. Paper published with permission.
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Cross, Stephen. "Membrane Concentration of Orange Juice". W ASME 1989 Citrus Engineering Conference. American Society of Mechanical Engineers, 1989. http://dx.doi.org/10.1115/cec1989-3504.
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A process to concentrate orange juice to levels above 42° Brix with quality close to fresh juice is discussed. Using ultrafiltration and reverse osmosis in a patented process, concentrate of superior quality can be produced. An overview of how membrane characteristics influence the design, selection and operation of the process is presented along with operating economics. Paper published with permission.
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SOETAREDJO, FELYCIA EDI, NANI INDRASWATI, ARTIK ELISA ANGKAWIJAYA i OSSY MARUSYA SJOUFRON. "ORANGE JUICE PASTEURIZATION USING OZONE". W Proceedings of the International Conference on CBEE 2009. WORLD SCIENTIFIC, 2009. http://dx.doi.org/10.1142/9789814295048_0101.
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Brocker, Paul P. "Aseptic Ingredient Addition: Meeting the Demand for Better-Tasting Orange Juice". W ASME 2006 Citrus Engineering Conference. American Society of Mechanical Engineers, 2006. http://dx.doi.org/10.1115/cec2006-5206.
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Since the late 1970’s, Aseptic Not-From-Concentrate Orange Juice (NFCOJ) has been successfully stored in large refrigerated aseptic storage tanks. Aseptic tanks have evolved from 280,000 gallons in volume to now in excess of 1.8 million gallons each. The total bulk storage capacity in Florida has grown to approximately 280 millions of gallons and continues to grow with new installations occurring each year at some facilities. Worldwide, the market is expanding into Brazil, Spain, and markets that are beginning to receive juice shipped in bulk on snips. The aseptic storage methods have been accepted in Brazil and Europe, and aseptic transfer of the juice is occurring via specially outfitted aseptic tanker vessels from Brazil to the US and Europe. The consumer’s demand for NFCOJ has grown steadily throughout these years, and the suppliers of consumer packaged orange juice have developed special processes and methods to maximize the quality and flavor of the juices sent to the market. Fresh juice, light pasteurization, and flavor enhanced products are just some of these methods resulting in very high quality juice availability. Also, cost and price are always under assault, and the juice suppliers are always looking for an edge. Recently, the flavor enhancement method has come under scrutiny by the FDA, and the industry is being reminded that all added flavors must be made from naturally occurring orange derivatives or must be labeled appropriately: such as “with natural (other fruit) flavors” or “with artificial flavors,” both of which may have an undesirable impact on the market perception of the juice quality. At this same time, as the bulk storage technology of NFCOJ has matured in the past 25 years, some processors who package their own juice are investing in special aseptic transfer methods from the aseptic bulk storage tanks without the need to re-pasteurize the juice prior to packaging. Their goal is to provide the highest quality juice to the consumer, and to minimize or eliminate the need to add expensive and special flavor packs to the juice. This is being done commercially in Florida and Spain. This paper explores these methods of aseptic juice transfer direct to packaging and the aseptic addition of natural or otherwise desired and labeled ingredients, and their potential impact on the quality of the juice. Paper published with permission.
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Redd, James B. "The Volatile Flavors of Orange Juice". W ASME 1988 Citrus Engineering Conference. American Society of Mechanical Engineers, 1988. http://dx.doi.org/10.1115/cec1988-3406.
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I want to thank the Florida Section of the American Society of Mechanical Engineers for the opportunity of talking with you about my favorite subject: “Orange Juice”. I’m a bit like the fellow from Texas who was visiting in Oklahoma. The town’s “ner-do-well” had passed away and at the local church, the minister was trying to say something nice about the departed. He soon ran out of words so he asked if someone in the audience cared to say a few words about the deceased. After a few moments of silence, the Texan got up and said that if nobody wanted to talk about the deceased, then he would like to take a few minutes to talk about Texas. That is how I feel about orange juice. Paper published with permission.
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Braddock, R. J., M. E. Parish i J. K. Goodner. "High Pressure Pasteurization of Citrus Juices". W ASME 1998 Citrus Engineering Conference. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/cec1998-4401.
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High hydrostatic pressures affect chemical reactions and phase changes of matter, denaturing proteins, solidifying lipids and disrupting biological membranes. The consequences of this in food systems has importance in killing spoilage microbes without the need for heat. Some applications of high pressure treatment to the processing of citrus juices are included herein. Effective pressures for pasteurization of yeasts and yeast ascospores in citrus juice fall in the range of 43,000–72,000 psi. The corresponding Dp (time for 1 log cycle reduction) values for inactivation of ascospores were 10 min at 43,000 psi or 8 sec at 72,000 psi. Pressure treatments of orange and grapefruit juices to by-pass thermal processing for pectinesterase (PE) inactivation were in the range of 72,000–130,000 psi. Dp values for orange PE inactivation at 72,000 and 87,000 psi were 83.3 minutes and 2.4 minutes, respectively. Pressures ≥87,000 psi caused instantaneous inactivation of the heat labile form, but did not inactivate the heat stable form of PE. Heat labile grapefruit PE was also more sensitive than orange to pressure. Orange juice pressurized at 100,000 psi for 1 minute had no cloud loss for >50 days. Paper published with permission.
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Gunter, Dan L. "Orange Juice Demand: An Industry in Transition". W ASME 1985 Citrus Engineering Conference. American Society of Mechanical Engineers, 1985. http://dx.doi.org/10.1115/cec1985-3104.
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Florida’s orange industry is facing an increasingly challenging production/marketing situation. Factors largely responsible for the current situation include demand growth and shifts in product demand, Florida freezes, and increased competition from Brazil. These factors will largely determine the position of the Florida industry in the orange juice market in the years ahead. Paper published with permission.
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Grant, Philip. "Homogenizing Concentrate in a Juice Evaporator". W ASME 1990 Citrus Engineering Conference. American Society of Mechanical Engineers, 1990. http://dx.doi.org/10.1115/cec1990-3604.
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A process used to concentrate orange juice and other citrus juices by using an APV Gaulin homogenizer within the T.A.S.T.E. Evaporator. The purpose of this process is to reduce viscosity, eliminate defects, reduce bottom pulp, increase yields, and provide for a smoother operation of the evaporator, subsequent to homogenization. This process, equipment and benefits are the basis of U.S. Patent #4,886,574 issued September 5, 1989, and application #339,171, pending. Paper published with permission.
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Norman, Seth I., i Dan A. Kimball. "A Commercial Citrus Debittering System". W ASME 1990 Citrus Engineering Conference. American Society of Mechanical Engineers, 1990. http://dx.doi.org/10.1115/cec1990-3601.
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Excessive bitterness in citrus juices has been extensively studied in the past due to a reduction in juice quality. In the late 1970’s, Australia began to commercially debitter citrus juices using cellulose acetate beads. However, due to operational problems, this plant was shutdown. Continued research has led to the first commercial debittering installation in the United States. Using a proprietary styrene/divinylbenzene hydrophylic adsorbent, a citrus debittering system was started in 1988 to debitter navel orange juice. The automatic citrus debittering system was designed for continuous operation at an operator’s selectable flow rate from between 20 to 55 gallons per minute. The determination of the economics, compositional analysis and taste of the treated products was the focus of this study. Paper published with permission.
Raporty organizacyjne na temat "Orange juice"
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Rouseff, Russell L., i Michael Naim. Characterization of Unidentified Potent Flavor Changes during Processing and Storage of Orange and Grapefruit Juices. United States Department of Agriculture, wrzesień 2002. http://dx.doi.org/10.32747/2002.7585191.bard.
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Citrus juice flavor quality traditionally diminishes after thermal processing and continuously during storage. Our prior studies found that four of the five most potent off-aromas formed during orange juice storage had not been identified. The primary emphasis of this project was to characterize and identify those potent flavor degrading aroma volatiles so that methods to control them could be developed and final flavor quality improved. Our original objectives included: 1 Isolate and characterize the most important unidentified aroma impact compounds formed or lost during pasteurization and storage. 2. Determination of thiamine and carotenoid thermal decomposition and Strecker degradation pathways in model solutions as possible precursors for the unidentified off-flavors. 3. Evaluate the effectiveness of an "electronic nose" to differentiate the headspace aromas of from untreated and heat pasteurized orange and grapefruit juices. 4. Use model systems of citrus juices to investigate the three possible precursor pathways (from 2) for flavor impact compounds formed or lost during pasteurization or storage. RESULTS - The components responsible for citrus storage off flavors and their putative precursors have now been identified. Certain carotenoids (b-carotene) can thermally degrade to produce b-ionone and b-damascenone which are floral and tobacco smelling respectively. Our GC-O and sensory experiments indicated that b-damascenone is a potential storage off-flavor in orange juice. Thiamine (Vitamin B1) degradation produces 2-methyl-3-furan thiol, MFT, and its dimer bis(2- methyl-3-furyl) disulfide which both produce meaty, savory aromas. GC-O and sensory studies indicated that MFT is another storage off-flavor. Methional (potato aroma) is another off flavor produced primarily from the reaction of the native amino acid, methionine, and oxidized ascorbic acid (vitamin C). This is a newly discovered pathway for the production of methional and is more dominant in juices than the classic Maillard reaction. These newly identified off flavors diminish the flavor quality of citrus juices as they distort the flavor balance and introduce non-typical aromas to the juice flavor profile. In addition, we have demonstrated that some of the poor flavor quality citrus juice found in the market place is not only from the production of these and other off flavors but also due to the absence of desirable flavor components including several potent aldehydes and a few esters. The absence of these compounds appears to be due to incomplete flavor volatile restoration after the making of juice concentrates. We are the first to demonstrate that not all flavor volatiles are removed along with water in the production of juice concentrate. In the case of grapefruit juice we have documented which flavor volatiles are completely removed, which are partially removed and which actually increase because of the thermal process. Since more that half of all citrus juices is made into concentrate, this information will allow producers to more accurately restore the original flavor components and produce a juice with a more natural flavor. IMPLICATIONS - We have shown that the aroma of citrus juices is controlled by only 1-2% of the total volatiles. The vast majority of other volatiles have little to no direct aroma activity. The critical volatiles have now been identified. The ability to produce high quality citrus juices requires that manufacturers know which chemical components control aroma and flavor. In addition to identifying the critical flavor components (both positive and negative), we have also identified several precursors. The behavior of these key aroma compounds and their precursors during common manufacturing and storage conditions has been documented so manufacturers in Israel and the US can alter production practices to minimize the negative ones and maximize the positive ones.
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Li, Lu, Nini Jin, Yueyue He, Kexin Ji, He Li, Chongde Sun i Xinqi Liu. Effects of chronic consumption of orange juice on cardiovascular risk factors in overweight and obese adults: a protocol for a systematic review and meta-analysis of randomized controlled trials. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, grudzień 2021. http://dx.doi.org/10.37766/inplasy2021.12.0082.
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Blumwald, Eduardo, i Avi Sadka. Citric acid metabolism and mobilization in citrus fruit. United States Department of Agriculture, październik 2007. http://dx.doi.org/10.32747/2007.7587732.bard.
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Accumulation of citric acid is a major determinant of maturity and fruit quality in citrus. Many citrus varieties accumulate citric acid in concentrations that exceed market desires, reducing grower income and consumer satisfaction. Citrate is accumulated in the vacuole of the juice sac cell, a process that requires both metabolic changes and transport across cellular membranes, in particular, the mitochondrial and the vacuolar (tonoplast) membranes. Although the accumulation of citrate in the vacuoles of juice cells has been clearly demonstrated, the mechanisms for vacuolar citrate homeostasis and the components controlling citrate metabolism and transport are still unknown. Previous results in the PIs’ laboratories have indicated that the expression of a large number of a large number of proteins is enhanced during fruit development, and that the regulation of sugar and acid content in fruits is correlated with the differential expression of a large number of proteins that could play significant roles in fruit acid accumulation and/or regulation of acid content. The objectives of this proposal are: i) the characterization of transporters that mediate the transport of citrate and determine their role in uptake/retrieval in juice sac cells; ii) the study of citric acid metabolism, in particular the effect of arsenical compounds affecting citric acid levels and mobilization; and iii) the development of a citrus fruit proteomics platform to identify and characterize key processes associated with fruit development in general and sugar and acid accumulation in particular. The understanding of the cellular processes that determine the citrate content in citrus fruits will contribute to the development of tools aimed at the enhancement of citrus fruit quality. Our efforts resulted in the identification, cloning and characterization of CsCit1 (Citrus sinensis citrate transporter 1) from Navel oranges (Citrus sinesins cv Washington). Higher levels of CsCit1 transcripts were detected at later stages of fruit development that coincided with the decrease in the juice cell citrate concentrations (Shimada et al., 2006). Our functional analysis revealed that CsCit1 mediates the vacuolar efflux of citrate and that the CsCit1 operates as an electroneutral 1CitrateH2-/2H+ symporter. Our results supported the notion that it is the low permeable citrateH2 - the anion that establishes the buffer capacity of the fruit and determines its overall acidity. On the other hand, it is the more permeable form, CitrateH2-, which is being exported into the cytosol during maturation and controls the citrate catabolism in the juice cells. Our Mass-Spectrometry-based proteomics efforts (using MALDI-TOF-TOF and LC2- MS-MS) identified a large number of fruit juice sac cell proteins and established comparisons of protein synthesis patterns during fruit development. So far, we have identified over 1,500 fruit specific proteins that play roles in sugar metabolism, citric acid cycle, signaling, transport, processing, etc., and organized these proteins into 84 known biosynthetic pathways (Katz et al. 2007). This data is now being integrated in a public database and will serve as a valuable tool for the scientific community in general and fruit scientists in particular. Using molecular, biochemical and physiological approaches we have identified factors affecting the activity of aconitase, which catalyze the first step of citrate catabolism (Shlizerman et al., 2007). Iron limitation specifically reduced the activity of the cytosolic, but not the mitochondrial, aconitase, increasing the acid level in the fruit. Citramalate (a natural compound in the juice) also inhibits the activity of aconitase, and it plays a major role in acid accumulation during the first half of fruit development. On the other hand, arsenite induced increased levels of aconitase, decreasing fruit acidity. We have initiated studies aimed at the identification of the citramalate biosynthetic pathway and the role(s) of isopropylmalate synthase in this pathway. These studies, especially those involved aconitase inhibition by citramalate, are aimed at the development of tools to control fruit acidity, particularly in those cases where acid level declines below the desired threshold. Our work has significant implications both scientifically and practically and is directly aimed at the improvement of fruit quality through the improvement of existing pre- and post-harvest fruit treatments.
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Porat, Ron, Doron Holland i Linda Walling. Identification of Citrus Fruit-Specific and Pathogen-Induced Promoters and Their Use in Molecular Engineering. United States Department of Agriculture, styczeń 2001. http://dx.doi.org/10.32747/2001.7585202.bard.
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This one year BARD project was funded to develop methods to monitor promoter activity a gene expression patterns in citrus fruit. To fulfill this goal, we divided the research tasks between both labs so that the Israeli side evaluated the use of microprojectile bombardment ; a tool to evaluate transient gene expression in various citrus fruit tissues, and the US side optimized technical parameters required for Agrobacterium-mediated transformation of various citrus cultivars. Microprojectile bombardment appeared to be a very efficient method for transient gene expression analysis in citrus leaf tissues but was somewhat less applicable in fruit tissues. Nevertheless, we did succeeded to achieve significant levels of 35S-GUS gene expression in young green flavedo tissue. However, only single random spots of 35S-GUS gene expression were detected mature flavedo and in juice sacs and albedo tissue. Overall, we assume that following some more technical improvements particle bombardment could provide a useful technique to rapidly analyze promoter activity at least in the flavedo tissue. For Agrobacterium-mediated transformation, we found that shoot cultures of 'Washington' navel oranges,'Fairchild' mandarins,'Eureca' lemons,'Troyer' citrange and various grapefruits provided a more reliable and consistent source of tissue for transformation than germinated seedlings. Moreover, various growth media's (McCown, Quoirin & Lepoivre, DCR) further improved shoot and root growth relative to MS mineral media, which is commonly used. Also pure white light (using bulbs which do not emit UV or blue light) improved shoot growth in various citrus varieties, and paromomycin appeared to be a more efficient antibiotic for the selection of transgenic plants than Kanamycin. Overall, these optimizations improve transformation efficacy and shoot growth and rooting capacity. In addition to the development of transformation methods, both Israeli and US labs achieved progress in the identification of citrus fruit-specific promoters. In Israel, we isolated a 3.6 kb promoter fragment of the thiamine biosynthesis c-thi gene, which is highly expressed in fruit peel tissue, whereas in the US we isolated a 1.5 kb promoter fragment of the citrus seed-specific cDNA CssH. The identification of more fruit-specific cDNAs and their corresponding promoter regions is currently in progress.