PROCESS FOR MAKING ETHANOL BY FERMENTATION

摘要

A process for making ethanol by fermentation comprises the steps fermenting a mash comprising a fermentable sugar with a yeast to form a fermented mash comprising ethanol, separating a yeast concentrate from the fermentation mash, adding a mineral acid to the yeast concentrate to provide an acidified yeast concentrate having a pH between 1.8 and 3.0, adding a peroxycarboxylic acid to the acidified yeast concentrate in an amount of from 5 to 80 ppm by weight to provide a treated yeast concentrate, and fermenting a mash comprising a fermentable sugar with addition of treated yeast concentrate to form a fermented mash comprising ethanol.

主权项

1. A process for making ethanol by fermentation comprising the steps
a) fermenting a mash comprising a fermentable sugar with a yeast to form a fermented mash comprising ethanol, b) separating a yeast concentrate from the fermentation mash obtained in step a), c) adding a mineral acid to the yeast concentrate obtained in step b) to provide an acidified yeast concentrate having a pH between 1.8 and 3.0, d) adding a peroxycarboxylic acid to the acidified yeast concentrate in an amount of from 5 to 80 ppm by weight to provide a treated yeast concentrate, and e) fermenting a mash comprising a fermentable sugar with addition of treated yeast concentrate obtained in step d) to form a fermented mash comprising ethanol.