38 research outputs found
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
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
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