Penetration of Yeast by Sugar during Grape Juice Fermentations

Abstract

An experimental and kinetic study was made of grape juice fermentations to throw more light on the process by which sugar enters yeast cells.

Rates of sugar consumption, yeast growth and production of alcohol and carbon dioxide were measured, and the fermentation rate data are interpreted with a mass-transfer-rate equation. The relation between the constant, k_s, obtained in this way and the Fick diffusion equation constant, D, is discussed. The rate constants obtained here are compared with those reported by other workers for various diffusion systems.