Search results for "fermentation"
showing 10 items of 746 documents
Bioaccessibility and bioavailability of bioactive compounds from yellow mustard flour and milk whey fermented with lactic acid bacteria.
2021
Microbial fermentation with lactic acid bacteria (LAB) is a natural food biopreservation method. Yellow mustard and milk whey are optimum substrates for LAB fermentation. The aim of the present study was to evaluate the bioaccessibility and bioavailability of bioactive compounds from yellow mustard flour and milk whey both with and without LAB fermentation. All extracts were subjected to a simulated digestion process. Total polyphenols, DL-3-phenyllactic acid (PLA), lactic acid, and the antioxidant activity were determined in the studied matrices before and after simulated digestion. Yellow mustard flour was significantly richer in total polyphenols, whereas significantly higher concentrati…
Methane production from orange peel pressing liquid: A kinetic study
1992
Abstract This paper studies the anaerobic fermentation of orange peel pressing liquid (OPPL), in semi‐continuous digesters under thermophilic conditions (50, 55 and 60°C), using rabbit manure as inoculum which has been previously conditioned to substrate and temperature. Experimental data have been fitted, at each temperature, to the Chen and Hashimoto model. Kinetic parameters governing the process have been obtained. It can be observed that both μm and K decrease when temperature increases, within the studied range, whereas the calculated minimum hydraulic retention time, θm, increases with temperature, as tested experimentally.
Modelling of an activated primary settling tank including the fermentation process and VFA elutriation
2002
A complete model of a primary settler including both sedimentation and biological processes is presented. It is a one-dimensional model based on the solids flux concept and the conservation of mass that uses the Takács model for the settling velocity, which is corrected by a compression function in the lower layers. The biological model is based on the ASM2 and enlarged with the fermentation model proposed by this research group. The settler was split in ten layers and the flux terms in the mass balance for each layer is obtained by means of the settling model. A pilot plant has been operated to study the primary sludge fermentation and volatile fatty acids (VFA) elutriation in a primary se…
Modeling and Analysis of a New Process for Pyruvate Production
2005
Early process development is crucial for the economic and environmental performance of a final production process. A new process for the production of pyruvate is presented as a case study to show how process modeling and an analysis of the results regarding economic and environmental aspects improves the understanding of the process, its cost structure, and its environmental impact. It also enables the quantification of process improvements and the comparison of alternative designs. The model of the pyruvate production shows how strain and fermentation improvements propagate through the process and affect its economic and environmental performance. The comparison of two alternative purific…
POEMS: A Case Study of an Italian Wine-Producing Firm
2006
Over the last decade, researchers paid much attention to concepts such as Design for Environment, Extended Producer Responsibility, Responsible Chain Management, and Eco-design. Many management tools and standards (such as EMAS, ISO 14001, LCA, EPD, Ecolabel) have been developed to support companies in the evaluation and management of their environmental performance and to pursue continual environmental improvement. The more recent development of the aforesaid fields looks at interorganizational environmental management. Such an approach can complement the more traditional intraorganizational corporate environmental management approaches and tools. A typical example of this new trend is the…
Non-Saccharomyces Yeasts: An Enzymatic Unexplored World to be Exploited
2019
Abstract Fermentation, to obtain alcoholic beverages, is a process which implies the interaction of various microorganisms. This metabolic process is due to the action of yeasts, which can be divided into two groups, the Saccharomyces yeasts, particularly S. cerevisiae, and the non-Saccharomyces yeasts. Although they are considered spoilage microorganisms of the fruits, non-Saccharomyces yeasts possess some interesting applied characteristics and can be used in food industry. Some of the compounds produced by these microorganisms may be beneficial and improve the characteristics of the fermented beverages. In this chapter, recent advances in glycosidase, xylanase, lipase, esterase, protease…
Characterization of EprA, a major extracellular protein of Oenococcus oeni with protease activity
2008
International audience; Extracellular proteins from Oenococcus oeni. a wine-making bacterium, were isolated during growth on media differing by their nitrogen content. Analysis by two-dimensional electrophoresis revealed a low number of protein signals. Among the main spots, one signal corresponded to a single protein, which contained a lysine repeat domain characteristic of cell-wall hydrolases. We demonstrated that this major protein, named EprA, was able to hydrolyse several proteins. The heterologous production of this protein in Escherichia coli confirmed the protease activity of EprA. With a MW of 21.3 kDa and a pl of 5.3, EprA presents optimal activity at pH 7.0 and 45 degrees C. Thi…
Laundry detergent compatibility of the alkaline protease from Bacillus cereus.
2004
The endogenous protease activity in various commercially available laundry detergents of international companies was studied. The maximum protease activity was found at 50 degrees C in pH range 10.5-11.0 in all the tested laundry detergents. The endogenous protease activity in the tested detergents retained up to 70% on incubation at 40 degrees C for 1 h, whereas less than 30% activity was only found on incubation at 50 degrees C for 1 h. The alkaline protease from an alkalophilic strain of Bacillus cereus was studied for its compatibility in commercial detergents. The cell free fermented broth from shake flask culture of the organism showed maximum activity at pH 10.5 and 50 degrees C. The…
Differential proteomic analysis highlights metabolic strategies associated with balhimycin production in Amycolatopsis balhimycina chemostat cultivat…
2010
Abstract Background Proteomics was recently used to reveal enzymes whose expression is associated with the production of the glycopeptide antibiotic balhimycin in Amycolatopsis balhimycina batch cultivations. Combining chemostat fermentation technology, where cells proliferate with constant parameters in a highly reproducible steady-state, and differential proteomics, the relationships between physiological status and metabolic pathways during antibiotic producing and non-producing conditions could be highlighted. Results Two minimal defined media, one with low Pi (0.6 mM; LP) and proficient glucose (12 g/l) concentrations and the other one with high Pi (1.8 mM) and limiting (6 g/l; LG) glu…
Stuck at work? Quantitative proteomics of environmental wine yeast strains reveals the natural mechanism of overcoming stuck fermentation
2015
During fermentation oenological yeast cells are subjected to a number of different stress conditions and must respond rapidly to the continuously changing environment of this harsh ecological niche. In this study we gained more insights into the cell adaptation mechanisms by linking proteome monitoring with knowledge on physiological behaviour of different strains during fermentation under model winemaking conditions. We used 2D-DIGE technology to monitor the proteome evolution of two newly discovered environmental yeast strains Saccharomyces bayanus and triple hybrid Saccharomyces cerevisiae × Saccharomyces kudriavzevii × S. bayanus and compared them to data obtained for the commercially a…