Characterisation of volatile flavour compounds in Roncal cheese extracted by the 'purge and trap' method and analysed by GC-MS

The objective of this study was to identify the volatile compounds characte ristic of Roncal Protected Denomination of Origin (AOC) cheese. Samples wer e taken from all the cheese makers registered with the Roncal AOC and were compared in the different periods of lactation. The equipment used was a 'p urge and trap' system coupled to a gas chromatograph operating with a mass- selective detector. A total of 68 compounds of the Following chemical famil ies were detected: hydrocarbons, fatty acids, esters, sulphur and carbonyl compounds and (especially) alcohols. Most of the volatile compounds extract ed with the purge and trap appeared in all seasons, but at different concen trations. This allowed a discriminate analysis to classify the samples by t he season in which they were made. (C) 2000 Elsevier Science Ltd. All right s reserved.