No abstract

No abstract

No abstract

Some of the factors that contribute to the loss of viability of brewery yeast strains during lyophilization (freeze-drying) have been investigated. A lyophilization technique for the maintenance of brewery yeast strains with higher viabilities than those previously reported has been developed. Three lyophilized strains of ale yeast still had a survival rate of 60% after periods of storage of up to three years, while a lager yeast strain maintained a viability of approximately 50% during storage for eighteen months.

Recent developments in the rapid detection of low concentrations of micro-organisms are discussed and their relevance to improved brewery quality control methods is assessed.A method based on the change in pH of a general purpose growth medium appears to offer the advantages of both time and sensitivity over methods currently in use.