Abscisic acid reduced methoxypyrazines concentration and its derived unpleasant odors in cabernet sauvignon grapes and wines.

Abstract

The influences of abscisic acid (ABA) applications on precursors and genes expression in 3-alkyl-2-methoxypyrazines (MPs) biosynthetic pathway, MPs concentration and sensory evaluation of its derived peculiar odors in Cabernet Sauvignon grapes and wines were studied. At the vineyard, ABA solution with 25, 100 and 400 mg/L (AT1, AT2 and AT3, respectively) and an aqueous solution (Control) were sprayed three times from veraison to pre-harvest. Higher concentration ABA applications (AT2 and AT3) in grapes could significantly reduce MPs concentration and its derived peculiar odors in grapes and wines than lower concentration ABA application (AT1) and control, with AT2 application having the strongest effect. The changes in MPs were mainly due to the downregulated expression of VvOMTs genes at higher concentration ABA applications, independent of the levels of their potential precursors. Our study reveals that ABA application had the potential to decrease production of MPs in Cabernet Sauvignon grapes and wines, and this result provides reference values for the removal of unpleasant vegetable odors from Cabernet Sauvignon wines in production. This article is protected by copyright. All rights reserved.