Zusammenfassung: Differences in the production of volatile flavour components in Swiss Gruyère cheese and supernatants of cultures of L. fermentum and L. delbrückii subsp. lactis were evaluated. The amount of `total` carbonyl components was determined, and the unknown components were identified and quantified by GC analysis. Furthemore, the correlation between sesiorially evaluated flavour scores and the amount of `total` carbonyl components was examined. The amount of `total` carbonyl components were significantly lower in supernatants of L. fermentum as well as in experimental cheese (with the addtion of L. fermentum) than in the supernatants of L. delbrückii subsp. lactis and in control cheese, respectively. These results have been confirmed by GC analysis of the corresponding culture supernatants. The strains of L. fermentum and L. delbrüuckii subsp. lactis examined showed significantly different productions of acetaldehyde, aceton and ethanol. In addition the strains of L. fermentum produced various acetic acid esters and 2-butanone, which could not be detected in the other strains tested. Finally no significant correlation could be established between the amount of `total` carbonyl components and flavour scores

Keywords: analysis, aroma, bah g, cheese, flavour, frm gruy?re, gruy?re, job, lactobacillus fermentum, lactobacillus lactis, liebefeld, microorganism, onr, pdo, switzerland, volatile compound,

Signatur: PUB Liebefeld