A PROCESS FOR PRODUCING FERMENTED ALCOHOLIC PRODUCTS WITH A LOW DIACETYL CONTENT

摘要

A process for producing fermented alcoholic products with a low diacetyl content, such as beer, wine or ethanol containing fermentation products to be processed to concentrated ethanol, comprises fermenting a carbohydrate containing substrate with a microorganism, preferably yeast, and treating the substrate with an acetolactate converting enzyme, such as acetolactate decarboxylase, during or in continuation of the fermentation. The process can also be used in connection with malo-lactic fermentation carried out during maturation of wine. The enzyme may be used in a free, dissolved state or in an immobilized state. In the acetolactate decarboxylase treatment small amounts of acetolactate formed by secondary fermentation processes are decarboxylated to acetoin instead of being slowly decomposed to diacetyl.