Apple Pomace Utilization for the Production of Baker's Yeast: Effect of Substrate Concentrations and Growth Stimulators

Abstract

Apple pomace powder showed higher percentage of fermentable sugar (to that of total), titratable acidity and

higher crude protein than molasses and jaggery. The composition of the extracted/diluted medium was in consistence

with the original substrates. Among the different total sugar concentrations tried (5, 10 & 15%),5% was optimum

for higher yeast biomass production. Comparing glucose with apple pomace extract (APE), molasses and jaggery,

glucose gave higher fermentation efficiency followed by APE, which was found superior with respect to higher

cellular yield coefficient and lower ethanol production. Addition of growth stimulators (vitamins & minerals)

increased efficiency of baker's yeast in both ways i.e. to respire or to ferment the available sugar. The different

carbon sources behaved similarly with respect to the addition of growth stimulators (minerals, vitamins and their

combinations) except APE medium, which exhibited a non-significant effect. Supplementing the APE medium with

such growth stimulators thus, is not required to produce baker's yeast.