In this study the combinatory effect of several extrinsic factors on reduced (vacuum) pressure fermentations was explored. Specifically, pressure, temperature, and FAN levels high gravity Saccharomyces cerevisiae were manipulated, while yeast morphology assessed using automated multivariate image analysis. Fermentation attributes including growth, viability, ethanol production monitored standar...

We are reporting on a novel self-aligned non-dispersive external cavity laser (ECL) based on thick volume holographic gratings (VHG). The ECL is tunable and operates with single mode and broad area multimode laser diodes. We experimentally demonstrate tunable single frequency operation at 405 nm and 785 nm. The tunable ECL concept is also experimentally tested with high power broad area laser d...

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...

Nowadays, vinegar is industrially produced by mesophilic acetic acid bacteria (AAB). However, temperature fluctuation during acetous fermentation is inevitable, and may cause process disturbances. This can be mostly avoided using thermo-tolerant AAB. The main purpose of the present study was to isolate thermo-tolerant AAB. Fermentation performances were then evaluated. Twenty-eight different is...

During brewery handling, production strains of yeast must respond to fluctuations in dissolved oxygen concentration, pH, osmolarity, ethanol concentration, nutrient supply and temperature. Fermentation performance of brewing yeast strains is dependent on their ability to adapt to these changes, particularly during batch brewery fermentation which involves the recycling (repitching) of a single ...

The most common way to produce red wine is through the use of Saccharomyces cerevisiae strains for alcoholic fermentation and lactic acid bacteria for malolactic fermentation. This traditional winemaking methodology produces microbiologically stable red wines. However, under specific conditions off-flavours can occur, wine quality can suffer and human health problems are possible, especially af...