Discriminate Analysis of the volatile fraction from "Terrincho" ewe cheese: Correlation with flavour characteristics

Abstract

"Terrincho" cheese is a semi-hard cheese variety made in Trás-os-Montes (North-Eastern Portugal) from "Churra da Terra Quente" raw ewes' milk using animal rennet as milk coagulant. headspace-solid phase microextraction coupled to a GC-MS was used to study the evolution of volatile compounds from this type of cheeses over 60 days of ripening, and to study the variability of the volatile fraction from "Terrincho" cheeses, from the same season, made at five different dairy plants. Panellists, trained to correlate the abundance of volatile compounds with quality and intensity of flavour, performed sensory evaluation of the "Terrincho" cheeses. A total of 82 compounds were identified. During ripening there was an overall increase in short-chain fatty acids, esters, alcohols and butanone. Discriminate analyses, using volatile compounds as variables, showed that it was possible to distinguish between cheeses ripened for different times and between "Terrincho" cheeses made at different dairy plants. Similar results were obtained for discriminate analyses of sensory profiles.