Littérature scientifique sur le sujet « Fermentation – Productivité »
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Articles de revues sur le sujet "Fermentation – Productivité"
1
Villen, Rafael Almud, Walter Borzani et Antonio Sacco Netto. « Influence of the accumulation of phosphate and magnesium ions in the yeast cells on the ethanol productivity in batch ethanol fermentation ». Brazilian Archives of Biology and Technology 52, no 1 (février 2009) : 153–55. http://dx.doi.org/10.1590/s1516-89132009000100020.
Texte intégralRésumé :
The accumulation of phosphate and magnesium in the yeast cells is not necessary to assure the ethanol productivity of batch ethanol fermentations. To avoid the decrease of the ethanol productivity it was sufficient to use a fermentation medium containing calculated concentrations of phosphorus and magnesium sources in order to maintain practically constant the phosphorus and magnesium initial contents of the biomass during the fermentation.
2
Capilla, Miguel, Carlos Silvestre, Alejo Valles, Francisco Javier Álvarez-Hornos, Pau San-Valero et Carmen Gabaldón. « The Influence of Sugar Composition and pH Regulation in Batch and Continuous Acetone–Butanol–Ethanol Fermentation ». Fermentation 8, no 5 (15 mai 2022) : 226. http://dx.doi.org/10.3390/fermentation8050226.
Texte intégralRésumé :
Acetone–butanol–ethanol (ABE) fermentation is influenced by external conditions. This work aimed to study the influence of pH regulation on monosaccharide composition in batch and continuous fermentation processes to determine butanol production and productivity. Batch fermentations with ammonium acetate or calcium carbonate combined with minimum pH control (pH ≥ 4.8 or 5.1) were assessed with pure xylose and glucose/xylose mixtures (ratios of 1:1 and 3:1). Continuous two-stage fermentation was developed using plastic rings to retain the biomass. Although batch fermentations with pure xylose performed better without active minimum pH control with both buffers, minimum pH control was necessary to metabolize xylose in the presence of glucose. Xylose uptake was favored by the use of calcium carbonate and pH ≥ 5.1 at a ratio of 1:1, while ammonium acetate and a pH ≥ 4.8 was the best option for a 3:1 ratio. The best butanol production and productivity values with sugar mixtures in batch reactors were 8.8 g L−1 and 0.61 g L−1 h−1 with an ammonium acetate pH ≥ 4.8 (ratio 3:1). The glucose/xylose ratio combined with pH regulation thus modulated xylose metabolism and solvent production in batch modes. Immobilized cells combined with operating at D = 0.333 h−1 and pH regulation increased butanol productivity almost fourfold up to 2.4 ± 0.2 g L−1 h−1.
3
Harcum, Sarah W., et Thomas P. Caldwell. « High Gravity Fermentation of Sugarcane Bagasse Hydrolysate by Saccharomyces pastorianus to Produce Economically Distillable Ethanol Concentrations : Necessity of Medium Components Examined ». Fermentation 6, no 1 (8 janvier 2020) : 8. http://dx.doi.org/10.3390/fermentation6010008.
Texte intégralRésumé :
A major economic obstacle in lignocellulosic ethanol production is the low sugar concentrations in the hydrolysate and subsequent fermentation to economically distillable ethanol concentrations. We have previously demonstrated a two-stage fermentation process that recycles xylose with xylose isomerase to increase ethanol productivity, where the low sugar concentrations in the hydrolysate limit the final ethanol concentrations. In this study, three approaches are combined to increase ethanol concentrations. First, the medium-additive requirements were investigated to reduce ethanol dilution. Second, methods to increase the sugar concentrations in the sugarcane bagasse hydrolysate were undertaken. Third, the two-stage fermentation process was recharacterized with high gravity hydrolysate. It was determined that phosphate and magnesium sulfate are essential to the ethanol fermentation. Additionally, the Escherichia coli extract and xylose isomerase additions were shown to significantly increase ethanol productivity. Finally, the fermentation on hydrolysate had only slightly lower productivity than the reagent-grade sugar fermentation; however, both fermentations had similar final ethanol concentrations. The present work demonstrates the capability to produce ethanol from high gravity sugarcane bagasse hydrolysate using Saccharomyces pastorianus with low yeast inoculum in minimal medium. Moreover, ethanol productivities were on par with pilot-scale commercial starch-based facilities, even when the yeast biomass production stage was included.
4
Omoruyi, G. O., I. O. Busari et O. J. Babayemi. « In-vitro assessment of the nutritive value of vegetable wastes as feed supplement for ruminants ». Nigerian Journal of Animal Production 49, no 5 (26 mai 2023) : 138–46. http://dx.doi.org/10.51791/njap.v49i5.3772.
Texte intégralRésumé :
The need to optimize livestock production to meet the growing demand for animal products has necessitated the efficient use of available resources, including crop wastes to enhance livestock productivity. Fifteen vegetable waste samples were analyzed to determine their nutritive value as ruminant feed. The chemical composition was determined using standard methods, and a 24-hour in-vitro fermentation was done to determine the dry matter degradability (DMD), short chain fatty acid (SCFA), and enteric methane (CH4) emission of each sample. Talinum triangulare leaf had the highest (p<0.05) crude protein value (31.50%) and Cucumis sativa had the lowest value (11.51%). A significant difference (p<0.05) was observed among the values of the proximate composition of the samples. Cucumis sativa had the highest CH4 percentage (36.75%) while the lowest CH4 percentage (10.00%) was observed in Cochorus olitorius stem. There was no significant difference (p<0.05) observed among the DMD values of the samples. The value of SCFA was highest for Daucus carota (0.33) and lowest for Talinum triangulare stem (0.07). The results of the proximate composition, CH4 percentage, and dry matter degradability of the samples observed in this study revealed that they could be further investigated through in-vivo trials to establish their suitability as alternative feedstuffs in ruminant diets.
La nécessité d’optimiser la production animale pour répondre à la demande croissante de produits animaux a nécessité l’utilisation efficace des ressources disponibles, y compris les déchets de récolte pour améliorer la productivité de l’élevage. Quinze échantillons de déchets végétaux ont été analysés pour déterminer leur valeur nutritive en tant qu’aliments pour ruminants. La composition chimique a été déterminée à l’aide de méthodes standard et une fermentation in vitro de 24 heures a été effectuée pour déterminer la dégradabilité de la matière sèche (DMS), les émissions d’acides gras à chaîne courte (AGCC) et de méthane entérique (CH4) de chaque échantillon. La feuille de Talinum triangulare avait la valeur de protéines brutes la plus élevée (p < 0,05) (31,50 %) et Cucumis sativa avait la valeur la plus faible (11,51 %). Une différence significative (p<0,05) a été observée entre les valeurs de la composition approximative des échantillons. Cucumis sativa avait le pourcentage de CH4 le plus élevé (36,75%) tandis que le pourcentage de CH4 le plus bas (10,00%) a été observé dans la tige de Cochorus olitorius. Aucune différence significative (p < 0,05) n’a été observée entre les valeurs DMS des échantillons. La valeur de AGCC était la plus élevée pour Daucus carota (0,33) et la plus faible pour la tige de Talinum triangulare (0,07). Les résultats de la composition approximative, du pourcentage de CH4 et de la dégradabilité de la matière sèche des échantillons observés dans cette étude ont révélé qu’ils pourraient être étudiés plus avant par des essais in vivo pour établir leur pertinence comme aliments alternatifs dans l’alimentation des ruminants.
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Ojo, Abidemi Oluranti, et Olga de Smidt. « Lactic Acid : A Comprehensive Review of Production to Purification ». Processes 11, no 3 (24 février 2023) : 688. http://dx.doi.org/10.3390/pr11030688.
Texte intégralRésumé :
Lactic acid (LA) has broad applications in the food, chemical, pharmaceutical, and cosmetics industries. LA production demand rises due to the increasing demand for polylactic acid since LA is a precursor for polylactic acid production. Fermentative LA production using renewable resources, such as lignocellulosic materials, reduces greenhouse gas emissions and offers a cheaper alternative feedstock than refined sugars. Suitable pretreatment methods must be selected to minimize LA cost production, as the successful hydrolysis of lignocellulose results in sugar-rich feedstocks for fermentation. This review broadly focused on fermentative LA production from lignocellulose. Aspects discussed include (i). low-cost materials for fermentative LA production, (ii). pretreatment methods, (iii). enzymatic hydrolysis of cellulose and hemicellulose, (iv). lactic acid-producing microorganisms, including fungi, bacteria, genetically modified microorganisms, and their fermentative pathways, and (v). fermentation modes and methods. Industrial fermentative lactic acid production and purification, difficulties in using lignocellulose in fermentative LA production, and possible strategies to circumvent the challenges were discussed. A promising option for the industrial production and purification of LA that contains enzyme and cell recycling continuous simultaneous saccharification and fermentation coupled with membrane-based separation was proposed. This proposed system can eliminate substrate-, feedback-, and end-product inhibition, thereby increasing LA concentration, productivity, and yield.
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Barbuto Ferraiuolo, Simona, Odile Francesca Restaino, Ignacio Gutiérrez-del-Río, Riccardo Ventriglia, Marcella Cammarota, Claudio J. Villar, Felipe Lombó et Chiara Schiraldi. « Optimization of Pre-Inoculum, Fermentation Process Parameters and Precursor Supplementation Conditions to Enhance Apigenin Production by a Recombinant Streptomyces albus Strain ». Fermentation 7, no 3 (21 août 2021) : 161. http://dx.doi.org/10.3390/fermentation7030161.
Texte intégralRésumé :
Streptomyces albus J1074-pAPI (Streptomyces albus-pAPI) is a recombinant strain constructed to biotechnologically produce apigenin, a flavonoid with interesting bioactive features that up to now has been manufactured by extraction from plants with long and not environmentally friendly procedures. So far, in literature, only a maximum apigenin concentration of 80.0 µg·L−1 has been obtained in shake flasks. In this paper, three integrated fermentation strategies were exploited to enhance the apigenin production by Streptomyces albus J1074-pAPI, combining specific approaches for pre-inoculum conditions, optimization of fermentation process parameters and supplementation of precursors. Using a pre-inoculum of mycelium, the apigenin concentration increased of 1.8-fold in shake flask physiological studies. In 2L batch fermentation, the aeration and stirring conditions were optimized and integrated with the new inoculum approach and the apigenin production reached 184.8 ± 4.0 µg·L−1, with a productivity of 2.6 ± 0.1 μg·L−1·h−1. The supplementation of 1.5 mM L-tyrosine in batch fermentations allowed to obtain an apigenin production of 343.3 ± 3.0 µg·L−1 in only 48 h, with an increased productivity of 7.1 ± 0.1 μg·L−1·h−1. This work demonstrates that the optimization of fermentation process conditions is a crucial requirement to increase the apigenin concentration and productivity by up to 4.3- and 10.7-fold.
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Hessa, Célestin Cokou, Yaya Idrissou, Alassan Seidou Assani, Hilaire Sorébou Sanni Worogo et Ibrahim Alkoiret Traoré. « Emissions de Gaz à Effet de Serre des Systèmes AgroSylvopastoraux et Sylvopastoraux de deux Zones Agroécologiques du Bénin ». European Scientific Journal, ESJ 20, no 12 (29 avril 2024) : 221. http://dx.doi.org/10.19044/esj.2024.v20n12p221.
Texte intégralRésumé :
Au Bénin, une typologie de quatre groupes d’éleveurs a été établie sur la base des deux pratiques agroforestières (agrosylvopastoralisme et sylvopastoralisme) en lien avec l'adaptation au changement climatique. Il s’agit : des petits agrosylvopasteurs (Groupe 1 : PAS), des petits sylvopasteurs (Groupe 2 : PSV), des grands sylvopasteurs (Groupe 3 : GSV), et enfin des grands agrosylvopasteurs (Groupe 4 : GAS). Les effets de ces pratiques sur la productivité du bétail ont été évalués et connus. Cependant, des informations sur les effets de ces pratiques sur l’émission de gaz à effet de serre (GES) font défaut. Ainsi, la présente étude permet de combler cette lacune. Pour l’atteinte de cet objectif, 180 éleveurs ont été enquêtés. Des données sur l'alimentation animale, la gestion du fumier et la composition des troupeaux ont été collectées, et l’outil GLEAM-i (Global Livestock Environmental Assessment Model interactive) de la FAO a été utilisé pour estimer les émissions de GES au sein de chaque type d’élevage. Les résultats ont révélé que les émissions de GES de tous les types d'élevage bovin étaient de 34,24 Gg CO2-eq/an dont les élevages GAS, GSV, PSV et PAS contribuaient respectivement pour 37,57 % ; 35,89% ; 13,87% et 12,67%. Dans tous les types d'élevage, le CH4 issu de la fermentation entérique était le principal contributeur aux émissions de GES. Les intensités d'émission du lait et de la viande étaient plus faibles dans les élevages GAS (60,21 kg CO2/kg de protéines du lait ; 178,68 kg CO2/kg de protéines de la viande) et PAS (61,61 kg de CO2/kg de protéines du lait ; 180,61 kg CO2/kg de protéines de la viande). Cette étude servira d'outil d'appui à l'élaboration de lignes directrices pour les systèmes de production animale à faibles émissions au Bénin et ailleurs en Afrique subsaharienne. In Benin, a typology of four groups of herders was established on the basis of two agroforestry practices (agrosilvopastoralism and silvopastoralism) related to adaptation to climate change. These are small agro-silvopastoral (Group 1: PAS), small silvopastoral (Group 2: PSV), large silvopastoral (Group 3: GSV), and finally large agro-silvopastors (Group 4: GAS). The effects of these practices on livestock productivity have been assessed and known. However, information on the effects of these practices on greenhouse gas (GHG) emissions is lacking. Thus, the present study fills this gap. To achieve this objective, 180 farmers were surveyed. Data on animal feed, manure management, and herd composition were collected, and the Global Livestock Environmental Assessment Model interactive (GLEAM-i) tool was used to estimate GHG emissions within each farming type. The results revealed that the GHG emissions of all cattle farming types were 34.24 Gg CO2-eq/year, of which GAS, GSV, PAS, and PSV breeding contributed respectively for 37.57 %; 35.89%; 13.87% and 12.67%. In all farming types, CH4 from enteric fermentation was the main contributor to GHG emissions. The emission intensities of milk and meat were lower in GAS (60,21 kg CO2/kg milk protein; 178.68 kg CO2/kg meat protein) and PAS (61.61 kg CO2/kg milk protein; 180.61 kg CO2/kg meat protein). This study will serve as a support tool for the development of guidelines for low-emission animal production systems in Benin and elsewhere in sub-Saharan Africa.
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Dolejš, Igor, Monika Líšková, Vladimír Krasňan, Kristína Markošová, Michal Rosenberg, Fabio Lorenzini, Andrew C. Marr et Martin Rebroš. « Production of 1,3-Propanediol from Pure and Crude Glycerol Using Immobilized Clostridium butyricum ». Catalysts 9, no 4 (31 mars 2019) : 317. http://dx.doi.org/10.3390/catal9040317.
Texte intégralRésumé :
The present study describes the production of the value-added chemical 1,3-propanediol (1,3-PD) from crude glycerol, a waste by-product formed during biodiesel production. The efficiency, robustness, and stability of the process were improved by immobilization of the anaerobic bacterium Clostridium butyricum into a polyvinyl alcohol (PVA) hydrogel. The highest average productivity, 6.8 ± 0.2 g/(L·h), was achieved in 10 consecutive, repeated batch fermentations, with an initial concentration of pure glycerol 45.5 ± 0.7 g/L, after 2.5 hours. The highest final concentration and yield of 1,3-PD, 28.3 ± 0.6 g/L, and 0.42 ± 0.01 g/g, respectively, were achieved in eleven repeated batch fermentations, after increasing the initial pure glycerol concentration to 70.4 ± 1.9 g/L. Two different types of crude glycerol, produced from used cooking oil (UCO) and rapeseed oil (RO), were tested in repeated batch fermentations, with an average productivity achieved of 2.3 ± 0.1 and 3.5 ± 0.3 g/(L·h), respectively. The highest final concentration and yield of 1,3-PD, 12.6 ± 0.9 g/L, and 0.35 ± 0.02 g/g, respectively, were observed in fifteen repeated batch fermentations with RO crude glycerol. An excellent stability of the immobilized anaerobic bacteria and increase of productivity in fermentation of crude glycerol was demonstrated.
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Iram, Attia, Ali Özcan, Ercan Yatmaz, İrfan Turhan et Ali Demirci. « Effect of Microparticles on Fungal Fermentation for Fermentation-Based Product Productions ». Processes 10, no 12 (13 décembre 2022) : 2681. http://dx.doi.org/10.3390/pr10122681.
Texte intégralRésumé :
Ranging from simple food ingredients to complex pharmaceuticals, value-added products via microbial fermentation have many advantages over their chemically synthesized alternatives. Some of such advantages are environment-friendly production pathways, more specificity in the case of enzymes as compared to the chemical catalysts and reduction of harmful chemicals, such as heavy metals or strong acids and bases. Fungal fermentation systems include yeast and filamentous fungal cells based on cell morphology and culture conditions. However, filamentous fungal fermentation has gained attention in the past few decades because of the diversity of microbial products and robust production of some of the most value-added commodities. This type of fungal fermentation is usually carried out by solid-state fermentation. However, solid-state fermentation poses problems during the scale-up for industrial production. Therefore, submerged fermentation for value-added products is usually preferred for scaling-up purposes. The main problem with submerged fungal fermentation is the formation of complex mycelial clumps or pellets. The formation of such pellets increases the viscosity of the media and hinders the efficient transfer of oxygen and nutrient resources in the liquid phase. The cells at the center of the clump or pellet start to die because of a shortage of resources and, thus, productivity decreases substantially. To overcome this problem, various morphological engineering techniques are being researched. One approach is the use of microparticles. Microparticles are inert particles with various size ranges that are used in fermentation. These microparticles are shown to have positive effects, such as high enzyme productivity or smaller pellets with fungal fermentation. Therefore, this review provides a background about the types of microparticles and summarizes some of the recent studies with special emphasis on the fungal morphology changes and microparticle types along with the applications of microparticles in filamentous fungal fermentations.
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Ogunbosoye, D. O., T. O. Abegunde, T. O. Binuomote et K. B. Salau. « Nutritional evaluation and growth response of West African dwarf (WAD) sheep fed varying levels of soybean cheese waste diets ». Nigerian Journal of Animal Production 49, no 4 (10 février 2023) : 166–75. http://dx.doi.org/10.51791/njap.v49i4.3713.
Texte intégralRésumé :
Feed shortage and high cost of conventional feed ingredients in the tropics and the keen competition between man and other farm animals necessitated the need to search for alternative feed resources that are cheap, available at all times but not toxic for ruminants to enhance their productivity. Hence, this study examined the fermentation characteristics and performance of West African dwarf (WAD) sheep fed graded levels of soybean cheese waste (SBCW). Three diets were formulated at 0%, 10% and 20% levels of SBCW respectively as D1, D2 and D3. Eighteen WAD sheep averaging 14 kg were randomly allocated to the dietary treatments for 102 days. The crude protein (CP) content of the diets varied significantly (p < 0.05) with CP of D1 being lowest (12.18 %) and highest in D3 (17.75 %). The gas volume produced at the end of 24 hrs incubation for D3 was lower than in D1 and D2. The methane volume produced was least in D3 and highest in D1. The calculated organic matter digestibility (OMD), metabolizable energy (ME) and short chain fatty acids (SCFA) values were similar except for D3 which had higher OMD than D1 and D2. Daily dry matter intake (DDMI) of WAD sheep fed D3 was highest compared to other diets. A similar trend was observed in average daily weight gain (ADWG). D3 had the least cost per kg of diet among the others. From the results obtained, it was observed that diet D3 appeared to be the best and economically viable for sheep production.
La pénurie d'aliments et le coût élevé des ingrédients alimentaires conventionnels dans les tropiques et la vive concurrence entre l'homme et les autres animaux d'élevage ont nécessité la recherche de ressources alimentaires alternatives bon marché, disponibles à tout moment mais non toxiques pour les ruminants afin d'améliorer leur productivité. Par conséquent, cette étude a examiné les caractéristiques de fermentation et les performances des West African Dwarf (WAD) sheep nourris avec des niveaux gradués de déchets de fromage de soja (DFS). Trois régimes ont été formulés à des niveaux de 0 %, 10 % et 20 % de DFS respectivement en tant que D1, D2 et D3. Dix-huit moutons WAD pesant en moyenne 14 kg ont été répartis au hasard entre les traitements diététiques pendant 102 jours. La teneur en protéines brutes (PB) des régimes variait significativement (p < 0,05), la PB de D1 étant laplus faible (12,18 %) et la plus élevée de D3 (17,75 %). Le volume de gaz produit au bout de 24 heures d'incubation pour J3 était inférieur à celui de D1 et D2. Le volume de méthane produit était le plus faible en D3 et le plus élevé en D1. Les valeurs calculées de digestibilité de la matière organique (DMO), d'énergie métabolisable (EM) et d'acides gras à chaîne courte (AGCC) étaient similaires, sauf pour D3 qui avait une DMO plus élevée que D1 et D2. L'apport quotidien en matière sèche (AQMS) des moutons WAD nourris au D3 était le plus élevé par rapport aux autres régimes. Une tendance similaire a été observée dans le gain de poids quotidien moyen (GPQM). D3 avait le moindre coût par kg de régime parmi les autres. D'après les résultats obtenus, il a été observé que le régime D3 apparaissait comme le meilleur et économiquement viable pour la production ovine.
Thèses sur le sujet "Fermentation – Productivité"
1
Ozcelik, Hayriye. « Productivity Analyses In Fermentations With Three Different Biolarvacides ». Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/3/12604988/index.pdf.
Texte intégralRésumé :
The development of insecticides resistance among many insect species and the ecological damage occasionally caused by the lack of specificity in the toxic effects of insecticides have provided the impetus to seek alternative methods of insect control. This observation led to the development of bioinsecticides based on the insecticidal action Bacillus sphaericus (Bs), Bacillus turingiensis (Bt).
The discovery of biolarvicidal actions of Bacillus thuringiensis and Bacillus sphaericus opened a new perspective for insect control.
In the first part of the study was initiated to determine a suitable fermentation medium formulation and optimal fermentation conditions for large scale, low cost production of Bs. Bs 2362 was tested in whey and soy flour based media. These media was reformulized form of NYSM (Nutrient Broth Yeast Extract Sporulation Medium). Soy flour based medium, SYSM, gave the promising results in terms of cell yield, sporulation frequency and toxin production.
In the second part of the study, fermentation productivity anlaysis of a local isolate Bacillus thuringiensis subsp. kurstaki 81 was evaluated. In order to compare different C:N ratios (1:1, 2:1, 4:1, 8:1, 10:1 20:1 and 30:1) of YSM medium. Btk 81 were run for 72 h and cell growth, sporulation and toxin protein profile of Btk 81 were determined for each. When all the quantitative toxin data for both glucose and sucrose varying C:N ratios were compared, it was determined that the crystal protein concentrations had the highest value in sucrose based medium when C:N ratio was 10:1.
Regulation by C:N ratio of crystal protein biosynthesis was investigated for improving the production of this protein by our third candidate strain Bacillus thuringiensis subsp. israelensis ONR60. The experiments were performed by using TBL medium, at three different C:N ratios, 2:1, 4:1 and 8:1 respectively. In view of the cell growth characteristics and bioassy results, TBL medium designed with 2:1 C:N ratio was chosen as the best for further steps. In addition, running time of the culture determined as 60 hours as was also determined in the previous experiment.
As the last step of this study, the pre-determined optimal conditions were applied to a 30L batch type fermentor for toxin production by using Bacillus thuringiensis subsp. israelensis ONR60. Unfortunately, the toxicity was not satisfactory, being much below the level of that expected as based on the results of the laboratory scale studies.
2
Lacerda, Filho Armando Marsden. « Fermentation systems for enhancement of ethanol productivity in Saccharomyces cerevisiae at elevated temperatures ». Thesis, University of St Andrews, 1996. http://hdl.handle.net/10023/14371.
Texte intégralRésumé :
Three Brazilian yeast strains, Saccharomyces cerevisiae 42 - F, Saccharomyces cereviaiae PLA 851 and Saccharomyces boulardli IZ 1904, all currently employed in the sugar fermentation industry, were evaluated with respect to their thermal tolerance and alcohol production kinetics. Best performance was found in Saccharomyces cerevisiae PLA 851 at temperatures up to 40 degrees (a common fermentation temperature in the Brazilian industry). This strain was further evaluated in chemostatic growth under sucrose limitation with biomass feedback on a 1 Litre scale in a specially constructed apparatus. At 30 degrees and 35 degrees under a dilution (growth) rate of 0.1 /h ethanol productivity increased by a factor of 2 with feedback and at 40 degrees by a factor of 3. The feedback factor (Beta) was 0.9. PLA 851 cells, heat - shocked at 45 degrees, resulted in a greater biomass productivity subsequently at 40 degrees coupled with a change in cell morphology. Highest ethanol productivity was found with 10% initial sucrose concentration at a dilution rate of 0.25 /h with feedback. Saccharomyces cerevisiae PLA 851 appears to be well adapted to the harsh physiological conditions in alcohol fermentations as currently practiced in Brazil.
3
Laouali, Mahaman Sani. « Mise au point d'une filière complète de traitement des eaux usées urbaines de régions tropicales : digesteur à biomasse fixée, lagunages à Microphytes et à Macrophytes, production piscicole ». Montpellier 2, 1990. http://www.theses.fr/1990MON20141.
Texte intégralRésumé :
Les experimentations ont porte sur deux filieres distinctes de traitement des eaux usees urbaines: 1) fermentation anaerobie+lagunage a microphytes+pisciculture; 2) fermentation anaerobie+lagunage a macrophytes ou sont cultivees des jacinthes d'eau+pisciculture. Le traitement primaire a ete optimise par des essais a differents temps de sejour hydraulique en reacteur anaerobie a 25c dans un reacteur de 5 m#3 equipe de support de biomasse a base de fibres synthetiques regroupees en pompons. Des abattements significatifs en dco ont ete observes. Des taux de croissance de 0,6 a 0,8 g/jour ont ete obtenus sur un elevage de tilapias dans les eaux epurees
4
Gomes, Elenice Mendes Silva. « Influência das concentrações de açúcares nos mostos sobre o desempenho da fermentação etanólica conduzida em batelada alimentada com vazão variável de alimentação ». Universidade Federal de Alagoas, 2011. http://www.repositorio.ufal.br/handle/riufal/1202.
Texte intégralRésumé :
This study aimed to evaluate the influence of concentrations of sugars in the must, on the performance of ethanol fermentation conducted in fed batch with variable flow of power to define the best concentrations of ART in the must (juice, molasses and mixed) that lead to improved efficiencies and productivity in ethanol fermentation.In the preparation of mash mix were used the following proportions (20% molasses + 80% broth, 40% molasses + 60% broth, 50% molasses + 50% broth, 60% molasses + 40% broth, 80% molasses + 20% broth ). The profile power was declining, varying the flow rate from 0.75 to 0.25 Lh-1, with time filling the fermenter 3 hours for all tests, ranging from 30 to 30 minutes to feed flow wort in fermenter 4L workload (3 liters of wine and 1 liter of inoculum), evaluating diferente concentrations of ART in three types of wine studied. We evaluated performance parameters such as fermentation and process efficiencies and productivity in ethanol. Musts were quantified in pH, sulfuric acid, Brix and ART.In the middle fermented (wine), pH, acidity, residual sugar and ethanol content and quantity of cells. The kinetic profile was defined by quantifying the concentrations of cells, substrate and ethanol (in 1 hour). The figures in this study as a starting point for industrial use are 16 to 18 Brix (ART 114.25 to 125.86 g / L), 16 to 18 ° Brix (ART 127.70 to 141.24 g / L) and around 16 ° Brix (ART 113.68 g / L to 123.30), respectively, for juice of molasses, juice and mix (juice + molasses).The fermentation efficiencies were 77.17 to 90.30% for grape juice, from 74.4 to 86.51% for wine and mixed wine from 61.84 to 84.06 for molasses. Yields were obtained from 6.85 to 8.21 g / Lh for wine broth, 5.90 to 7.77 g / Lh for wine mixed and 4.04 to 6.72 g / Lh for grape molasses. These tracks serve to subsidize recommended as a starting point, the conduct of industrial ethanol fermentation conducted in fed batch with variable flow supply, since the conditions for conducting the tests, as well as the raw materials used in the preparation of musts were similar to those used industrially.Fundação de Amparo a Pesquisa do Estado de Alagoas
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Este estudo objetivou avaliar a influência das concentrações de açúcares nos mostos, sobre o desempenho da fermentação etanólica conduzida em batelada alimentada com vazão variável de alimentação, para a definição das melhores concentrações de ART nos mostos (de caldo, de melaço e misto) que conduzam a melhores eficiências de fermentação e produtividade em etanol. Na preparação do mosto misto foram utilizadas as seguintes proporções (20% melaço + 80% caldo, 40% melaço + 60% caldo, 50% melaço + 50% caldo, 60% melaço + 40% caldo, 80% melaço + 20% caldo). O perfil de alimentação foi decrescente, variando-se a vazão de 0,75 a 0,25 L.h-1, com tempo de enchimento do fermentador de 3 horas para todos os ensaios, variando-se de 30 em 30 minutos a vazão de alimentação de mosto, em fermentador de 4L de volume de trabalho (3 litros de mosto e 1 litro de inoculo), avaliando-se diferentes concentrações de ART nos 3 tipos de mosto estudados. Foram avaliados parâmetros de desempenho, como eficiências fermentativa e de processo e produtividade em etanol. Nos mostos foram quantificados pH, acidez sulfúrica, Brix e ART. No meio fermentado (vinho), pH, acidez, Açúcares Residuais e teor de etanol e quantidade de células. O perfil cinético foi definido, quantificando-se as concentrações de células, substrato e etanol (em intervalos de 1 hora). Os valores indicados neste estudo, como ponto de partida para utilização industrial, são Brix de 16 a 18 (ART 114,25 a 125,86 g/L), de 14 a 18 °Brix (ART de 112,90 a 141,24 g/L) e próximo de 16 °Brix (ART de 113,68 g/L a 123,30), respectivamente para mostos de melaço, caldo e misto (caldo + melaço). As eficiências de fermentação foram: 77,17 a 90,30%, para mosto de caldo, 74,4 a 86,51% para mosto misto e 61,84 a 84,06 para mosto de melaço. As produtividades obtidas foram 6,85 a 8,21g/L.h, para mosto de caldo, 5,90 a 7,77g/L.h para mosto misto e 4,04 a 6,72g/L.h para mosto d melaço. Estas faixas recomendadas servem para subsidiar, como ponto de partida, a condução da fermentação etanólica industrial conduzida em batelada alimentada com vazão variável de alimentação, visto que as condições de condução dos ensaios, assim como as matérias-primas utilizadas na preparação dos mostos, foram semelhantes às utilizadas industrialmente.
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Lee, Jungeun. « Sustainable Production of Microbial Lipids from Renewable Biomass : Evaluation of Oleaginous Yeast Cultures for High Yield and Productivity ». Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35300.
Texte intégralRésumé :
Doctor of PhilosophyDepartment of Grain Science and Industry
Praveen V. Vadlani
Microbial lipids derived from oleaginous yeasts are a promising alternative source of edible oils due to the following advantages: no requirement of broad lands; availability of year-round production; and no food versus fuels controversy. Oleaginous yeast has an inherent ability to accumulate lipids inside cells and their lipids are preferable as starting materials in oleo-chemical industries because of their distinct fatty acid composition. Lignocellulosic biomass is a promising substrate to supply carbon sources for oleaginous yeast to produce lipids due to the high content of polysaccharides and their abundancy. Lignocellulosic-based sugar streams, which can be generated via pretreatment and enzymatic hydrolysis, contained diverse monosaccharides and inhibitors. The major objectives of this study were: 1) to develop a novel purification method to generate clean sugar stream using sorghum stalks after acid pretreatment; 2) to optimize fermentation conditions for Trichosporon oleaginosus to achieve high yields and productivity of microbial lipids using lignocellulosic hydrolysates; 3) to investigate the potentials of sorghum stalks and switchgrass as feedstocks for microbial lipid production using oleaginous yeast strains, such as T. oleaginosus, Lipomyces starkeyi, and Cryptococcus albidus; 4) to develop an integrated process of corn bran based-microbial lipids production using T. oleaginosus; and 5) to develop bioconversion process for high yields of lipids from switchgrass using engineered Escherichia coli. In our investigation, major inhibitory compounds of lignocellulosic hydrolysates induced by pretreatment were acetic acid, formic acid, hydroxymethyl furfural (HMF) and furfural. The activated charcoal was effective in removing hydrophobic compounds from sorghum stalk hydrolysates. Resin mixtures containing cationic exchangers and anionic exchangers in 7:3 ratio at pH 2.7 completely removed HMF, acetic acid, and formic acid from sorghum stalk hydrolysates. T. oleaginosus was a robust yeast strain for lipid production. In the nitrogen-limited synthetic media, total 22 g/L of lipid titers were achieved by T. oleaginosus with a lipid content of 76% (w/w). In addition, T. oleaginosus efficiently produced microbial lipids from lignocellulosic biomass hydrolysates. The highest lipid titers of 13 g/L lipids were achieved by T. oleaginosus using sorghum stalk hydrolysates with a lipid content of 60% (w/w). L. starkeyi and C. albidus also successfully produced microbial lipids using lignocellulosic hydrolysate with a lipid content of 40% (w/w). Furthermore, corn bran was a promising feedstock for microbial lipid production. The highest sugar yields of 0.53 g/g were achieved from corn bran at the pretreatment condition of 1% acid and 5% solid loading. Microbial lipids were successfully produced from corn bran hydrolysates by T. oleaginosus with lipid yields of 216 mg/g. Engineered E. coli also effectively produced lipids using switchgrass as feedstocks. E. coli ML103 pXZ18Z produced a total of 3.3 g/L free fatty acids with a yield of 0.23 g/g. The overall yield of free fatty acids was 0.12 g/g of raw switchgrass and it was 51 % of the maximum theoretical yield. This study provided useful strategies for the development of sustainable bioconversion processes for microbial lipids from renewable biomass and demonstrated the economic viability of a lignocellulosic based-biorefinery.
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Claret, Carole. « Métabolismes oxydatif et fermentaire du glycérol chez les bactéries : étude physiologique et cinétique de sa conversion en dihydroxyacétone et en 1,3-propanediol ». Toulouse, INSA, 1992. http://www.theses.fr/1992ISAT0034.
Texte intégralRésumé :
L'etude cinetique et physiologique de la conversion du glycerol en dihydroxyacetone par gluconobacter oxydans montre que cette fermentation est soumise a une double inhibition. L'effet inhibiteur du substrat se manifeste par une diminution des cinetiques de croissance et de production avec l'augmentation de la teneur en glycerol, modelisee par des lois de type exponentiel. Cet effet est essentiellement lie a l'abaissement de l'activite de l'eau par les concentrations elevees en substrat. L'inhibition par la dha se manifeste tout d'abord par une diminution des cinetiques de croissance et d'oxydation du substrat (faibles concentrations) puis par un blocage du developpement cellulaire et de la synthese de dha (concentrations elevees). Ces phenomenes, modelises par des lois de levenspiel, ont ete attribues a la forte reactivite de la dha avec les enzymes cytoplasmiques et impliques dans le transport du glycerol et avec la glycerol deshydrogenase membranaire, responsable de la formation de dha. Un procede bi-phasique mono-etage, integrant ces contraintes biologiques, a alors ete mis au point, permettant d'ameliorer les performances fermentaires de cette transformation. Le metabolisme fermentaire du glycerol a ete aborde sous un angle microbiologique. Deux micro-organismes responsables de la degradation du glycerol au sein d'une flore microbienne anaerobie ont ete isoles et caracterises: clostridium butyricum cncm 1. 1211, qui transforme le glycerol en 1,3-propanediol et butyrate avec des rendements de conversion respectifs de 0,66 et 0,13; enterobacter agglomerans cncm 1. 1210, espece nouvellement decrite pour ses capacites d'assimilation du glycerol et de conversion de ce substrat en acetate et 1,3-propanediol (rendements respectifs de 0,25 et 0,7). La preponderance du role joue par le systeme accepteur final d'equivalents reducteurs sur la regulation du metabolisme fermentaire quelle que soit l'espece microbienne etudiee a egalement ete definie
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邱毓明. « Hydrogen-Productivity Comprison of Four types of Anaerobic Fermentation Reactors ». Thesis, 2002. http://ndltd.ncl.edu.tw/handle/35235154753452033928.
Texte intégralRésumé :
碩士臺中師範學院
環境教育研究所
90
The conventional anaerobic wastewater treatments are able to deal with various types of organic wastewater and able to recovery biogas, which is mainly methane. Based on the regulation of the Framework Convention On Climate Change, methane is the next item to be put under control due to its greenhouse effect. Hydrogen produced by anaerobic fermentation can be used as an energy source with no greenhouse effect and therefore, become a highly potential technique with a great commercial market. After considering the physiological characteristics and growth condition of anaerobic hydrogenic bacteria, this study has designed 4 typical reactors suitable for anaerobic hydrogenesis , including Sludge recycling reactor, Continuous flow stirred tank reactor (CSTR), Non-mixing conventional reactor, and Plug flow reactor. The hydrogen productivity and wastewater treatment efficiencies of these 4 reactors were compared to evaluate which is the best for anaerobic production of hydrogen. The best operation condition of each reactor was also determined. As the results shown, within the influent COD concentration being 2,000-15,000 mg/L and HRT being 6-24 hrs, the hydrogen productivity is the best with an organic loading of 60 kg-COD/m3×d. Among these 4 reactors, continuous flow stirred tank reactor is the most appropriate for anaerobic fermentation hydrogenesis with a hydrogen productivity of 150 ml/g-CODre and a hydrogen productivity of per unit reactor of 774 L-H2/m3×d（1atm,25℃）, followed by non-mixing conventional reactor with a hydrogen productivity of 129 ml/g-CODre and a hydrogen productivity of per unit reactor of 646 L-H2/m3×d（1atm,25℃）. Only at a higher organic loading, sludge recycling reactor has a higher efficiency of hydrogen production due to the higher total production with a hydrogen productivity of 74.9 ml/g-CODre（1atm,25℃） and a hydrogen productivity of per unit reactor of 1100 L-H2/m3×d（1atm,25℃）. The hydrogen productivity of each reactor was increased with the increase of organic loading and the decrease in HRT, furthermore, the effect of HRT was more significant. At an organic loading of 2 kg-COD/m3×d, all reactors have the best COD removal, ranging from 54.0 to 60.1%, due to the highly methanation at the low organic loading. At an organic loading of 60 kg-COD/m3×d, all reactors have the worst COD removal, ranging from 9.0 to 19.0%. The COD removal of each reactor was decreased with the increase in organic loading and the decrease in HRT. From the observation under the fluorescent microscope and electron microscope, it was found that yellow-orange fluorescence was emitted by a large amount of Clostridium bacteria in biomass while the anaerobic fermentation hydrogenesis was good. However, blue fluorescence, which indicated a highly methanation, was emitted while the anaerobic fermentation hydrogenesis was poor. These results may be helpful in determining the efficiency of anaerobic fermentation hydrogensis .
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ChenChang, Chia, et 張嘉真. « Productivity simulation of combined sugar and ethanol production with selective fermentation technology ». Thesis, 2015. http://ndltd.ncl.edu.tw/handle/10409251462345150493.
Texte intégralRésumé :
碩士國立成功大學
環境工程學系
103
Selective fermentation realized by invertase-defective yeasts that convert only the reducing sugars in a mixed saccharide (e.g. sugarcane juice) into ethanol is an emerging process technology in sugarcane industry. This technology opens possibilities in stabilization and enhancement of total productivity of sugar and ethanol, as productive and stronger cultivars that have higher content of reducing sugar becomes a potential raw material in sugar mills. To trigger the system-wide innovation of this technology, the changes in stability and enhancement of productivity must be described by changes in cultivars and cropping schedules. Here, a descriptive model developed in this study highlights consequences of introduction of selective fermentation technology considering a given scenario on choice of cultivars and cropping schedules. Moreover, utilizing a prototype database, design of scenarios based on optimization techniques are demonstrated. The results from demonstrative scenario design indicate the potential advantages of selective fermentation technology in combination with a cane cultivar with high yield, high biomass and reducing sugar content on Tanegashima Island of Japan. The study also indicates the new requirement on data from sugarcane cultivation, such as a wider range of growth profiles (stalk weight, composition), growth and harvest observations of perennial ratoon and rate of physical damage by typhoon by varied rationing months. Future directions of study including directions in enhancement of the model and database are discussed.
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ZENG, WEN-GI, et 曾文祺. « Effect of fermentation conditions on the growth of recombinant saccharomyces cerevisiae and HBsAg productivity ». Thesis, 1988. http://ndltd.ncl.edu.tw/handle/16356562196326261863.
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Huang, Chong-ruey, et 黃重睿. « Increasing Productivity of Bio-ethanol by Using Pichia stipitis Fermentation in Continuous Dual-tank ». Thesis, 2011. http://ndltd.ncl.edu.tw/handle/78154135746176485488.
Texte intégralRésumé :
碩士大葉大學
生物產業科技學系
99
To avoid grain prices rising and causing inflation, production of the biomass fuel alcohol of the second era is mostly abandoned grain crops, and used the non-grain crops of abounded biomass cellulose or agriculture waste as raw materials. The saccharides that biomass fiber through preprocessing hydrolysis and producing are used by organism methods for fermentation to get alcohol, and the saccharides of the kind of raw materials obtained possess the two classes of five carbon and six carbon. In order to amply use these reducing sugars, developing co-fermentation process is an important topic. The bacteria strains that are able to ferment five carbon saccharides are quite rare in the nature world, and therefore using gene recombination to develop new bacteria strains is an important work. Besides the fermentation rate of the five carbon saccharides is quite slow, and therefore the rising of efficiency is also an important research. This research is according to the earlier established Pichia stipitis fermentation model, and analyzing the efficiency problem of two-tank continuous fermenting glucose and xylose the mixture solution to produce alcohol. The used substrate sources of two-tank continuous fermentation, in accordance with preprocessing, can be classified as 50 g/L pure glucose and the mixture solution of 8 g/L glucose/24 g/L xylose, the two sorts. Therefore, this research is designed that tank-one and tank-two are particular fed one kind of substrates, and the first tank is fed two kinds of substrates at the same time, et cetera, many kinds of operating method, to confer ethanol production rate, ethanol produced ratio, and substrate used ratio, et cetera, the variation under respective sorts of combination, and analyze the ethanol production rate. When comparing two-tank continuous fermenting and one-tank continuous fermenting, two-tank ethanol production rate is not certainly higher, but substrate used ratio is higher. For example of pure glucose fed, one-tank ethanol production rate in dilution rate 0.06 1/hr is 0.24 g/L/hr, and substrate used ratio is 0.265; and two-tank ethanol production rate, in the first and second dilution rate particularly 0.06 1/hr and 0.30 1/hr, is 0.232 g/L/hr, and substrate used ratio is 0.306. And the case of the first tank fed mixture solution substrates and the second tank fed pure glucose of two-tank continuous fermenting, mixture solution fed dilution rate 0.015 – 0.1 1/hr, and pure glucose fed dilution rate 0.050 1/hr, and dilution rate of liquid flowing from the first tank into the second tank 0.0005 1/hr, equivalent to the volume of the second tank being at least 30 times of the volume of the first tank, can get the most ideal ethanol production rate 0.267 g/L/hr, but neither ethanol produced ratio 0.323 nor substrate used ratio 0.34 are ideal. Because dilution rate is lower, ethanol production rate is lower, but ethanol produced ratio and substrate used ratio are higher. That is ethanol produced ratio and substrate used ratio needing sacrificing in order to obtain the highest ethanol production rate.
Chapitres de livres sur le sujet "Fermentation – Productivité"
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Rebello, Sharrel, Embalil Mathachan Aneesh, Raveendran Sindhu, Parameswaran Binod, Ashok Pandey et Edgard Gnansounou. « Enzyme Catalysis : A Workforce to Productivity of Textile Industry ». Dans High Value Fermentation Products, 49–65. Hoboken, NJ, USA : John Wiley & Sons, Inc., 2019. http://dx.doi.org/10.1002/9781119555384.ch3.
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Xu, Jie, Anu Das, Jarrod Erbe, L. M. Hall et Kenneth B. Taylor. « Genetic Engineering for Productivity in the Fermentation of Xylose to Ethanol ». Dans Conversion And Utilization Of Waste Materials, 169–80. Boca Raton : Routledge, 2023. http://dx.doi.org/10.1201/9781315140360-14.
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Carro, M. D., et E. M. Ungerfeld. « Utilization of Organic Acids to Manipulate Ruminal Fermentation and Improve Ruminant Productivity ». Dans Rumen Microbiology : From Evolution to Revolution, 177–97. New Delhi : Springer India, 2015. http://dx.doi.org/10.1007/978-81-322-2401-3_13.
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Wang, Jing, Jinglin Zhou et Xiaolu Chen. « Soft-Transition Sub-PCA Monitoring of Batch Processes ». Dans Intelligent Control and Learning Systems, 59–77. Singapore : Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-8044-1_5.
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AbstractBatch or semi-batch processes have been utilized to produce high-value-added products in the biological, food, semi-conductor industries. Batch process, such as fermentation, polymerization, and pharmacy, is highly sensitive to the abnormal changes in operating condition. Monitoring of such processes is extremely important in order to get higher productivity. However, it is more difficult to develop an exact monitoring model of batch processes than that of continuous processes, due to the common natures of batch process: non-steady, time-varying, finite duration, and nonlinear behaviors. The lack of exact monitoring model in most batch processes leads that an operator cannot identify the faults when they occurred. Therefore, effective techniques for monitoring batch process exactly are necessary in order to remind the operator to take some corrective actions before the situation becomes more dangerous.
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Oh, J., et A. N. Hristov. « Effects of Plant-Derived Bio-Active Compounds on Rumen Fermentation, Nutrient Utilization, Immune Response, and Productivity of Ruminant Animals ». Dans ACS Symposium Series, 167–86. Washington, DC : American Chemical Society, 2016. http://dx.doi.org/10.1021/bk-2016-1218.ch011.
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Rao, Raman, Paramjeet Dhull, Shilpa et Sachin Kumar. « Recent Advances and Challenges in Biobutanol Production ». Dans Green Gasoline, 109–23. Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/bk9781837670079-00109.
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In recent years, changes in crude oil prices and environment-related issues have compelled the scientific community to look towards renewable resources for the biological production of butanol. Butanol is considered an advanced biofuel owing to its environmentally friendly nature and superior qualities compared with ethanol. The production of butanol via biotechnological routes has some drawbacks, such as product inhibition, high cost of the substrate, low butanol productivity and incomplete knowledge of the microbial genome. To improve butanol productivity, it is necessary to have a deep knowledge of the functioning of genes in metabolic and regulatory pathways and to develop some advanced metabolic engineering tools. This chapter highlights genetic modifications to improve the solvent tolerance capacity of microbial strains, the development of effective microbial consortia for biomass fermentation and different fermentation types employed for high-titer butanol production. The chapter also sheds light on some globally adapted advanced fermentation techniques such as physiochemical and biological pretreatment methods, simultaneous saccharification and fermentation (SSF) and consolidated bioprocessing (CBP) to enhance butanol production from lignocellulosic biomass. These potential solutions will strengthen the hope of having a cost-effective and energy-efficient butanol production process in the near future.
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Ahmed Soltan, Yosra, et Amlan Kumar Patra. « Ruminal Microbiome Manipulation to Improve Fermentation Efficiency in Ruminants ». Dans Animal Feed Science and Nutrition - Health and Environment [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101582.
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The rumen is an integrated dynamic microbial ecosystem composed of enormous populations of bacteria, protozoa, fungi, archaea, and bacteriophages. These microbes ferment feed organic matter consumed by ruminants to produce beneficial products such as microbial biomass and short-chain fatty acids, which form the major metabolic fuels for ruminants. The fermentation process also involves inefficient end product formation for both host animals and the environment, such as ammonia, methane, and carbon dioxide production. In typical conditions of ruminal fermentation, microbiota does not produce an optimal mixture of enzymes to maximize plant cell wall degradation or synthesize maximum microbial protein. Well-functioning rumen can be achieved through microbial manipulation by alteration of rumen microbiome composition to enhance specific beneficial fermentation pathways while minimizing or altering inefficient fermentation pathways. Therefore, manipulating ruminal fermentation is useful to improve feed conversion efficiency, animal productivity, and product quality. Understanding rumen microbial diversity and dynamics is crucial to maximize animal production efficiency and mitigate the emission of greenhouse gases from ruminants. This chapter discusses genetic and nongenetic rumen manipulation methods to achieve better rumen microbial fermentation including improvement of fibrolytic activity, inhibition of methanogenesis, prevention of acidosis, and balancing rumen ammonia concentration for optimal microbial protein synthesis.
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Ojukwu, Moses, Chigozie Emmanuel Ofoedu, Chijioke M. Osuji et Ogbonnaya Okoro Aja. « Recent Advances in the Utilisation of Artificial Intelligence in the Food Industry ». Dans Advances in Environmental Engineering and Green Technologies, 299–317. IGI Global, 2023. http://dx.doi.org/10.4018/979-8-3693-0819-6.ch012.
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Global population growth raises food security concerns. AI, like computer vision and ML, revolutionizes agriculture. It monitors crop health, predicts yields, and automates tasks. Mobile apps diagnose crop diseases swiftly, boosting productivity. AI-driven machine vision improves food processing by flaw identification and quality control. AI sorting enhances item classification, increasing productivity. In beer production, AI ensures fermentation quality. It optimizes distribution, predicts demand, and reduces waste. AI detects contaminants for food safety. Chatbots offer personalized recommendations. Data privacy and ethics matter, requiring explainable AI (XAI) and legal frameworks must be addressed despite these advancements. AI promises a secure, efficient, and sustainable food ecosystem.
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Bitew, Dagnew, et Berhanu Andualem. « Diacetyl Production During Brewing and its Management Through Process Optimization and Molecular Evolution of Yeast ». Dans New Advances in Saccharomyces. IntechOpen, 2024. http://dx.doi.org/10.5772/intechopen.1003823.
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Diacetyl is butter-tasting off-flavor compound produced as by-product of yeast valine metabolism during brewery fermentation. Yeasts produce diacetyl during primary fermentation and then reabsorb it in secondary fermentation. This causes a non-productive lengthy maturation period, which is costly. Several strategies have been proposed to manage diacetyl and improve the productivity of brewery industries. This review aimed to assess diacetyl production and proposed strategies to manage diacetyl production during brewing. Diacetyl production and its amount in the green beer are influenced by brewing condition and type of strain used. Green beer conditioning and brewing process optimization are regarded as simple and feasible approaches. However, these have their own inherent drawbacks. On the other hand, a plethora of researches declared that genetic manipulation of yeasts is an effective strategy in reducing diacetyl amount and ultimately to shorten the maturation period and thereby maximize profitability of brewery industries. But the applicability genetic engineering limited, due to firm regulation of utilization of genetically modified organisms in food processing industries. Therefore, though extensive research was done on identifying and understanding factors which influence yeast diacetyl formation and reduction, diacetyl management is persisting as a challenge in brewing systems.
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Murguia-Fierro, Salma Verónica,. « Evaluation of obtaining biohydrogen by different fermentation methods ». Dans Young researchers Engineering Applications, 61–70. ECORFAN, 2023. http://dx.doi.org/10.35429/p.2023.1.61.70.
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There are a lot of projects around the methods of obtaining renewable fuels that are less harmful to the environment. In that sea of investigations, one of the less explored and with greater potential to become a principal biofuel is biohydrogen production through fermentations. However, biohydrogen technologies production has limitations such as low productivity, therefore are not profitable yet. Through this project, the search for the evaluation of practice to attain biohydrogen to determine how feasible the development of said technology, as well as the efficiency as a process is the main goal. In this project, development of multiple fermentations, analysis of growth curves in different growth mediums such as nutrient agar, BBM and TAP mediums in addition with microalgae Chlamydomonas, were made
Actes de conférences sur le sujet "Fermentation – Productivité"
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Mathew, Anil, Mitch Crook, Keith Chaney et Andrea Humphries. « Bioethanol Production From Canola Straw Using a Continuous Flow Immobilized Cell System ». Dans ASME 2012 6th International Conference on Energy Sustainability collocated with the ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/es2012-91061.
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Global cultivation of canola increased by approximately 22% between 2000 and 2009, due to increased demand for canola oil for biodiesel production and as an edible oil. In 2009 over 290,000 km2 of canola was cultivated globally. In contrast to oilseed, the commercial market for canola straw is minimal and it is generally ploughed back into the field. The high carbohydrate content (greater than 50 % by dry weight) of canola straw suggests it would be a good feedstock for second-generation bioethanol production. There are four major steps involved in bioethanol production from lignocellulosic materials: (i) pretreatment, (ii) hydrolysis, (iii) fermentation, and (iv) further purification to fuel grade bioethanol through distillation and dehydration. Previous research demonstrated a glucose yield of (440.6 ± 14.9) g kg−1 when canola straw was treated using alkaline pretreatment followed by enzymatic hydrolysis. Whilst bioethanol can be produced using cells free in solution, cell immobilization provides the opportunity to reduce bioethanol production costs by minimizing the extent to which down-stream processing is required, and increasing cellular stability against shear forces. Furthermore, the immobilization process can reduce substrate and product inhibition, which enhances the yield and volumetric productivity of bioethanol production during fermentation, improves operational stability and increases cell viability ensuring cells can be used for several cycles of operation. Previous research used cells of Saccharomyces cerevisiae immobilized in Lentikat® discs to convert glucose extracted from canola straw to bioethanol. In batch mode a yield of (165.1 ± 0.1) g bioethanol kg−1 canola straw was achieved. Continuous fermentation is advantageous in comparison to batch fermentation. The amount of unproductive time (e.g. due to filling, emptying and cleaning) is reduced leading to increased volumetric productivity. The higher volumetric productivity of continuous fermentation means that smaller reactor vessels can be used to produce the same amount of product. This reduces the capital costs associated with a fermentation plant. Research demonstrated a higher bioethanol yield was attained (224.7 g bioethanol kg−1 canola straw) when glucose was converted to bioethanol using immobilized cells in packed-bed continuous flow columns. On an energy generation basis, conversion of 1 kg of canola straw to bioethanol resulted in an energy generation of 6 MJ, representing approximately 35% energy recovery from canola straw. The amount of energy recovered from canola straw could be improved by increasing the amount of energy recovered as bioethanol and by utilising the process by-products in a biorefinery concept.
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Abdullah, Abdullah, Hario Satmoko et Wahyu Zuli Pratiwi. « Types and variations of buffer concentrations effect on biohydrogen productivity from sago dregs with fermentation method ». Dans THE 2ND INTERNATIONAL SYMPOSIUM OF INDONESIAN CHEMICAL ENGINEERING 2021 : Enhancing Innovations and Applications of Chemical Engineering for Accelerating Sustainable Development Goals. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0113935.
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