Buffer, Lactic Fermentation, and Rennet Coagulation Properties of Skim Milk Retentates Produced by Ultrafiltration

Abstract
The buffer, lactic fermentation potential and rennet coagulation of direct ultrafiltration retentates of skim milk were studied. Retentates concerned 5 fold (18.5% total solids) and acidified directly or through a lactic acid fermentation displayed a dB/dpH value at pH 5.1 7 times greater than original skim milk. The buffering capabilities rose exponentially with increasing total solids. Rennet-coagulation behavior of ultrafiltration retentate was similar to that of milk. Successive reductions of 50% in rennet extended coagulation time by a factor of 1.9 .+-. .05.