Utilisation of spent brewer's yeast for yeast extract production by autolysis: the effect of temperature.

摘要

Use of autolysis to obtain yeast extract from spent brewer's yeast was investigated. Cell suspensions of spent brewer's yeast were incubated for 8-72 h at 40-60 degrees C. Yields and contents of solids, protein, carbohydrate and alpha-amino N were measured. Based on alpha-amino N and protein contents, optimal conditions for yeast extract production were incubation for 24 h at 50 degrees C. Sensory properties of the yeast extract were evaluated by adding it to vegetable soup at concn. of 0.5-2.0% (w/v). Overall acceptance was highest for soup containing 0.5 or 1.0% yeast extract. Addition of higher amounts led to an unacceptable, heavy flavour. However, none of the samples were described as being bitter, suggesting that the debittering element of the process is effective.