Evaluation of individual lactic acid bacteria for the fermentation of goat milk: Quality parameters

Abstract

Nine lactic acid bacteria (LAB) were evaluated as single cultures for goat milk fermentation with the aim to assess their suitability as adjunct cultures. Performance of the cultures was assessed based on technological and product quality parameters and their comparison with a commercial mixed culture. Volatile compounds profile, odor descriptors, acidification rate, microbial counts, gel stability, organic acid and sugar profiles, conjugated linoleic acid (CLA) content, were determined. Most LAB reached counts over 7-log cfu/g, gel stability assessed by centrifugation (average: 64% loss) and whey composition (average: 0.32% protein, 0.24% fat, 4.4% lactose, 3.5% dry matter) and CLA content (1.16% of total fatty acids) were not affected by the assayed cultures. Main differences among fermented milks relied on volatiles (mainly acids and ketones), odor descriptors and sugar metabolism (glucose, galactose and lactic acid). The present study provides useful information for the selection of cultures for goat milk products.