Application de bentonite aux moûts en fermentation: effet sur la formation et évolution du méthanol et des alcools supérieurs en deux cépages de la région des “Vinhos Verdes”, Loureiro et Trajadura

Comissão de Viticultura da Região dos Vinhos Verdes

The continuous manufacturing of terpin

The continuous or semi-continuous production of terpin from a-pinene by hydration, using 40S sulfuric acid as a catalyst, was studied in a batch laboratory reactor as well as at pilot scale. It was concluded that the mixing intensity affects the distribution of products and that the greatest yields are obtained in a semi-continuous or continuous process

Changes in aromatic characteristics of loureiro and alvarinho wines during maturation

Changes in volatiles during maturation in bottles of monovarietal Vinhos Verdes wines from Loureiro and Alvarinho grape varieties, were followed by chemical and sensory analyses. Young wines and wines matured for 8 and 20 months were studied. The volatiles were determined by gas chromatography– mass spectrometry (GC-MS) after extraction on XAD-2 resin. Straight chain fatty acid ethyl esters and acetates of fusel alcohols decreased quicker for Loureiro wine, while the increase in ethyl esters of branched fatty acids was similar for both varieties. Linalool, Ho-trienol, a-terpineol and b-damascenone could be used to differentiate between each variety. However, linalool decreased to negligible values after 20 months of maturation. b-Damascenone decreased but remained high enough to be useful for differentiating each variety. Sensory analysis indicated a decrease of tropical fruit and tree fruit characters with conservation time for Alvarinho wine, and the opposite for Loureiro; moreover, citrus fruit character decreased in both varietiesCentre of Biological Engineering of Universidade do Minho (CEB-UM); Estação Vitivinícola Amândio Galhano (EVAG); Solar de Serrade; Comissão de Viticultura da Região dos Vinhos Verdes