Influence of harvesting techniques, grape crushing and wine treatments on the volatile components of white wines

Trebbiano white grapes were harvested both by hand and mechanically, with the addition of O2 and SO2 at crushing in the vineyard. After wine-making in standard conditions, the wines were cla rified with different fining agents.The wines were tested to identify the volatile components. The method developed included solvent extraction, concentration, GLC and GLC/MS an alysis. Over 60 compounds were ide ntified, some of which were previously unidentified.Only some volatile components were significantly affected by the harvesting techniques or by clarification treatments. The hyperoxygenation of the crushed grapes lowered the aroma profile, improving the content of the more oxidized molecules. The S02 addition increased maceration phenomena, but decreased wine stability to browning reactions. The wine finishing with bentonite and other clarifying additives resulted in a loss of some aroma compounds due to volatilization

Experiences with solid CO2 concentration of bergamot cold-pressed essential oil (Citrus bergamia Risso)

Sublimation of solid CO2 selectively removed hydrocarbons from bergamot oil. This result was achieved in a laboratory with very simple equipment. The oil and dry ice were mixed in a cylindrical vessel and the gas stream entrained most of non-oxygenated terpenes. Their behavior is discussed briefly