Characterization of Some Mushroom and Earthy Off-Odors Microbially Induced by the Development of Rot on Grapes

• Published in: Journal of agricultural and food chemistry Vol. 54; no. 24; pp. 9193 - 9200
• Main Authors: La Guerche, Stephane, Dauphin, Brunhilde, Pons, Monique, Blancard, Dominique, Darriet, Philippe
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 29-11-2006
• Subjects: alcoholic fermentation; Aspergillus; Biological and medical sciences; biosynthesis; Botrytis cinerea; Coniothyrium; Food engineering; Food industries; Food Microbiology; food spoilage; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; fungi; grape must; Humans; Life Sciences; Mass Spectrometry; microbial contamination; odor compounds; Odorants; off odors; Penicillium; plant rots; Rhizopus nigricans; Rhizopus stolonifer; Saccharomyces cerevisiae; Saccharomyces cerevisiae - metabolism; Vitaceae; Vitis - microbiology; volatile organic compounds; wine grapes; wine yeasts; wines; Yeast; Fruit; gray rot; earthy; Vitis vinifera; Characterization; Fungi; Vitidaceae; Dicotyledones; Rot; Grape; Angiospermae; 2-methylisoborneol; Development; Ascomycetes; Spermatophyta; Odor; Saccharomyces cerevisiae; geosmin; Edible fungi; 1-octen- 3-ol; Thallophyta; 1-octen-3-one
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf0615294

Grape rot is one of the major causes of degradation of many grape components and, thus, of deterioration in wine quality. In particular, the association of Botrytis cinerea with other, less visible, fungi frequently leads to the development of organoleptic defects in grapes and sometimes in wines. This study examines the nature of the volatile compounds responsible for mushroom, mossy, or earthy odors detected by gas chromatography−olfactometry in organic extracts of rotten grapes and musts. 2-Methylisoborneol, (−)-geosmin, 1-octen-3-one, 1-octen-3-ol, 2-octen-1-ol, and 2-heptanol were identified or tentatively identified. Their concentrations in musts were determined, and the impact of alcoholic fermentation by the yeast Saccharomyces cerevisiae was studied. The ability of fungi isolated from rotten grapes (Botrytis cinerea; Penicillium species including P. brevicompactum, P. expansum, P. miczynskii, P. pinophilum, P. purpurogenum, and P. thomii; Aspergillus section nigri; Rhizopus nigricans; and Coniothyrium sp.) to produce some of the identified compounds was evidenced. Keywords: Vitis vinifera; grape; gray rot; earthy; 2-methylisoborneol; geosmin; 1-octen-3-one; 1-octen-3-ol; Saccharomyces cerevisiae