Control of process time and beer quality in high gravity fermentations.

Jackson, A.P.

Abstract
The need for greater throughput and even better utilisation of brewing capacity to satisfy customer demand led to the adoption of high gravity brewing at South African Breweries. Experience over a 7 year period demonstrated that progressively higher wort gravity, up to 16 degrees P can be fermented by Saccharomyces uvarum without extended fermentation time. Besides controlled temperature increase an optimum level of wort dissolved oxygen is essential. Where wort contains free amino nitrogen in excess of 200 ppm, yeast growth has to be stimulated by yeast food. Acid washing of yeast has a positive affect on fermentation rate and drinkability.
Keywords : acid washing beer brewing fermentation high gravity brewing nitrogen oxygen Saccharomyces uvarum