Research Article

An industry and university joint effort to profile the sensory and chemical impacts of freeze-killed grape leaves in Cabernet Sauvignon from Washington state.

Project Investigator: Jim Harbertson, associate professor of enology, Washington State University

Grape leaves killed by frost become brittle and break down rapidly into “confetti-sized” bits. Mechanical sorting methods are often not sensitive enough to cleanly pick the leaves from the grape or sort them on the crush pad. Manual methods of sorting are possible but not always practical, except for high-premium wine tiers. For red wines, macerated styles of leaving skins and seeds on the juice can allow the frozen leaf “tea’ to steep into the wine. The frozen grape leaves infuse a flavor profile of their own that mask important markers of wine quality, such as color, aromatic complexity and astringency. This article presents a summary of the findings presented in a scientific journal.

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Enology //