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ENARTIS VINQUIRY 7795 Bell Road - Windsor, CA 95492 Tel: 707 838 6312 - Fax: 707 838 1765 www.enartisvinquiry.com The indications supplied are based on our current knoledge and experience, but do not relieve the user from adopting the necessary safety pr ecautions. Revision: July 2012 Recommendations for Color Stabilization in Red Wines Produced by Flash Détente Flash Détente and Thermovinification In red wine production, one of the most important process steps is the extraction of color compounds from grape skins. Classic maceration at “low” temperatures. 75-90°F (24-32°C), requires a rather long contact ti me and a bulky environment. One way of accelerating co lor and polyphenol extraction is through thermovinification. In the thermovinification process, crushed and de-stemmed grapes are pumped to a t ubular heat exchanger where the must is heated for a few minutes at 176-185° (80-85°C). This allows immediate inactivation of all endogenous enzymes (in particular oxydases like tirosinase and laccase produced by botrytis etc.), and a fast, efficient extraction of anthocyanins and tannins. The heated product is then piped to a cooling system where the te mperature is lowered to 95-104°F (35-40°C) in 10-15 minutes. Flash Détente is the modern evolution of the traditional thermovinification method. Crushed and de-stemmed grapes are rapidly heated to 176-185° (80-90°C). The heated must is then pi ped to a vacuum flash cooling system where the temperature is rapidl y lowered to 86-90°F (30-32°C). This flash cooling causes an intercellular explosion in grape skins, thus favoring better color extraction and avoiding the appearance of jammy characteristics which often appeared in classically thermovinified wines. Frequently, thermovinified and Flash Détented grapes are pressed and then fermented without skins, similar to white juice. In thi s way, wineries can produce red wines while saving space (less tanks). Among the major problems face d in fermenting without skins are • the huge loss of color during fermentation; • the appearance of vegetal/reductive characters. Loss of color is a consequence of a lack of quantity/quality o f extracted tannins. Flash Détente is highly effective in color extraction, but extracts onl y the most soluble tannins (l ow molecular weight). Extraction of larger and more complex t annins requires alcohol. This explains why thermovinified wines fermented without skins often lack structure and balance. FLASH DÉTENTE
