Contribution of autochthonous lactic acid bacteria to the typical flavour of raw goat milk cheeses

Abstract

In this study, a collection of 298 wild strains of lactic acid bacteria (LAB) isolated from raw goat milk cheeses, belonging to 8 genera and 24 species, was investigated for their ability to generate volatile compounds. Sensory evaluation showed that goat milk cultures of Leuconostoc and Lactococcus strains reached the highest scores for dairy odour attributes. Fifty six LAB strains with the highest sensory evaluation scores (one per each ten, or fraction, of those belonging to the same species) were selected for gas chromatography-mass spectrometry (GC-MS) analysis. A total of 34 volatile compounds (five carboxylic acids, eleven alcohols, six aldehydes, six ketones, one ester, and five miscellaneous compounds) were detected in lactic curds made with each one of 56 selected LAB strains. The number of volatile compounds in individual curds varied from 15 to 33 while the total abundance of volatile compounds in individual curds ranged from 1.98- to 17.50-fold the total abundance in uninoculated curd. Major differences in volatile generation were related to amino acid catabolism.