Effect of Leaf Content and Mechanical Harvest on Wine "Quality"

Abstract

No overall adverse effect on wine quality was produced by mechanically harvesting grapes or adding shredded grape leaves. In all cases, however, white wines made from damaged or machine-harvested grapes, or from grapes to which leaves had been added, were significantly darker by visual assessment as well as by absorbance at 420 nm. The phenolic content of wines increased with the addition of leaves or with berry damage.