Effects of nisin addition on the ethanol fermentation of casein whey permeate

Abstract

Nisin added at up to 1000 IU ml −1 did not affect ethanol production or cell growth during fermentation of sulphuric acid casein whey permeate by Kluyveromyces marxianus Y-113. Nisin reduced the bacterial population markedly when added at 100 IU ml −1 to whey permeate contaminated by addition of incubated cultures derived from milk or whey. The ethanol production rate and yield in the contaminated cultures treated with nisin did not differ from the control values