The Influence of Temperature on Some Properties of Yeast

Abstract

The effects of temperature on the growth of yeast and on its metabolic activity in distiller's malt wort have been studied. In un-aerated fermentations, maximum yeast production takes place at about 30°C. whereas the growth rate in aerated cultures is highest at 35°C. The lag phase of the yeast studied fell from 6 hr. at 20°C. to 2-8 hr. at 25°C. and was not thereafter greatly affected by increases of temperature until 42°C. was reached, at which point growth ceased. Maltase activity was maximal at 25°C. when considered in terms of unit quantities of either yeast or fermenting wort, but the optimum temperature for initial fermentation velocity varied according to the time over which the measurement was made, being maximal at 40°C. for 0-5 hr., and at 35°C. for 2 hr. Alcohol production was highest at 25°C. whereas glycerol and higher alcohol formation took place optimally at 30°C. merritt: influenxe of temperature on yeast Vol. 72, 1966] merritt: influence of temperature on yeast [J. Inst. Brew.

Produção de álcoois superiores por linhagens de Saccharomyces durante a fermentação alcoólica

“…RANKINE (1967) também verificou decréscimo no álcool n-propílico e aumento nos álcoois isobutílico e isoamílico em temperaturas mais elevadas de fermentação. Essas diferenças provavelmente poderiam ser explicadas pela levedura utilizada e variação da temperatura, pois MERRITT (1966) relatou que a temperatura ótima para a produção de álcoois superiores foi de 30°C enquanto os dados da TABELA l mostram maior produção a 34°C. A maior produção nessa temperatura poderia ser explicada pelo menor crescimento das leveduras em temperaturas mais elevadas conforme observado por GUTIERREZ (1989), assim os cetoácidos não sendo utilizados para a síntese de aminoácidos, seriam convertidos em álcoois superiores, embora NORDSTROM & CARLSSON (1965) não tenham encontrado correlação entre a formação de álcoois e o crescimento da levedura.…”

On-line identification of fermentation processes for ethanol production

“…The corn ethanol industry commonly employs the Saccharomyces cerevisiae yeast in the fermentation. As it does not produce the enzymes required for starch decomposition [72], this secretion was not a concern in this work. In this context, the model presented here is an unstructured one.…”

Systematic Investigation on Production and Quality Evaluation of Lugdi: A Traditional Alcoholic Beverage of Himachal Pradesh, India

“…To the slurry, water was added up to the brim and the mixture was allowed to ferment (2-3 days during summers and 6-7 days in winters). The increased fermentation rate during the summers might have been due to the shortening of lag phase as the lag phase decreases with increase in temperature (Merrit, 1966). During fermentation, the mouth of the pot was left uncovered and the absence of air bubbles on the top of the pot was used as an indicator for completion of fermentation.…”