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The localisation of some aroma components in the different parts of the berry of Muscat grape varieties was studied. The evolution of these compounds was also monitored during the development and maturation of the fruit. The aromatic substances were certain terpenols in free and glycosidically bound forms and certain aromatic alcohols, benzyl and 2-phenyl ethyl alcohols. The skin was the richest in free and bound terpenols in the berry. The ratio of bound free terpenols in skin, pulp and juice was similar. Free terpenols (in particular geraniol and nerol) were much more abundant in skin than in juice. It was possible to distinguish between the two Muscat varieties studied here using their levels of bound terpenols. These were abundant from the green stage of the grape berry onwards; their levels increased during development of the fruit to reach very high levels at the end of maturation. The bound terpenols have a considerable aroma potential, mainly located in grape skins, which it would be interesting to make use of in new wine technology.

Volatile constituents of experimental wines from five white vine cultivars (Terret, Ugni Blanc, Clairette, Sauvignon, Picpoul) and from five red vine cultivars (Cinsaut, Carignan, Grenache, Cabernet-Sauvignon, Syrah) were analysed using standard liquid-liquid extraction, chemical fractionation, adsorption chromatography on silica gel, low-and high-performance gas-liquid chromatography and gas chromatographymass spectrometry. One hundred and twenty two substances were positively identified and 15 tentatively identified. Fourteen of them had not been detected previously in wine. Some sensory evaluation of the various separated compounds was also attempted and a total of 131 volatile constituents were quantified in triplicate with calculation of the 95% confidence limits. The proportions and biogenesis of these constituents are briefly discussed.

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