Nitrogen supplementation, which is widely used in winemaking to improve fermentation kinetics, also affects the products of fermentation, including volatile compounds. However, the mechanisms underlying the metabolic response of yeast to nitrogen additions remain unclear. We studied the consequences for Saccharomyces cerevisiae metabolism of valine and ammonium pulses during the stationary phas...

Abstract This study was aimed to produce pear cider (Perry), using small caliber pears cv Abate Fètel, fermented by Starmerella bacillaris and Saccharomyces cerevisiae in co-inoculated (COF) sequential (SEF) mixed cultures comparison with S. monoculture fermentation (AXF), evaluating the influence of yeast starter on Perry characteristics. The perries were re-fermented bottle strain EC1118. Dur...

The phasing out of antibiotic compounds as growth promoters from the animal industry means that alternative practices will need to be investigated and the promising ones implemented in the very near future. Fermentation in the gastrointestinal tract (GIT) is being recognized as having important implications for health of the gut and thus of the host animal. Fermentation in single-stomached anim...

V. NAYDENOVA, V., S. VASSILEV, M. KANEVA and G. KOSTOV, 2013. Encapsulation of brewing yeast in alginate/ chitosan matrix: comparative study of beer fermentation with immobilized and free cells. Bulg. J. Agric. Sci., Supplement 2, 19: 123–127 In the present study, the possibilities for beer production with lager brewing yeasts, encapsulated in alginate/chitosan matrix with a liquid core, were i...

Tannase (tannin acyl hydrolase, E.C.3.1.1.20) is an important hydrolysable enzyme with innumerable applications and industrial potential. In the present study, a kinetic model has been developed for the batch fermentation used for the production of tannase by A.flavus MTCC 3783. Maximum tannase activity of 143.30 U/ml was obtained at 96 hours under optimum operating conditions at 35oC, an initi...

Two different types of immobilized yeast bioreactors were examined for continuous fermentation of high-gravity worts. One of these is a fluidized bed reactor (FBR) that employs porous glass beads for yeast immobilization. The second system is a loop reactor containing a porous silicon carbide cartridge (SCCR) for immobilizing the yeast cells. Although there was some residual fermentable sugar i...

The sequential inoculation of non-Saccharomyces yeasts and Saccharomyces cerevisiae in grape juice is becoming an increasingly popular practice to diversify wine styles and/or to obtain more complex wines with a peculiar microbial footprint. One of the main interactions is competition for nutrients, especially nitrogen sources, that directly impacts not only fermentation performance but also th...

This article proposes a methane production approach through sequenced anaerobic digestion of kitchen waste, determines the hydrolysis constants and reaction orders at both low total solid (TS) concentrations and high TS concentrations using the initial rate method, and examines the population growth model and first-order hydrolysis model. The findings indicate that the first-order hydrolysis mo...