Pierce's Disease
Research Updates

piercesdisease.cdfa.ca.gov

What is Pierce's Disease?

Pierce's Disease is a bacterial infection, which is spread by bugs that feed on grapevines, particularly the "glassy winged sharpshooter." Grapevines that become infected with PD can quickly become sick and die.

glassy-winged sharpshooter

A preliminary study of non-coloured phenolics in wines of varietal white grapes (codega, gouveio and malvasia fina): effects of grape variety, grape maturation and technology of winemaking


  • Author(s): Andrade, P.; Faia, M.; Ferreira, M.; Pereira, C.; Ramos, R.; Seabra, R.;
  • Abstract: The effects of cultivar, grape maturation and technology of winemaking on the levels of phenolic acids were evaluated. In all varieties, 3,4-dihydroxybenzoic, p-coumaric and caffeic acids were the predominant acids. Among the three varieties, significant differences were observed in the concentration of p-coumaric acid. The grape maturation only influenced the concentration of 3,4-dihydroxybenzoic acid. According to the technology of winemaking, significant differences could be observed in syringic, and p-coumaric acids by the induction of fermentation temperature. Comparisons of the phenolic composition, when the fermentations were conducted in stainless steel tanks and/or in oak barrels, showed differences in the concentrations of 3,4-dihydroxybenzoic, ellagic and caffeic acids. (C) 1999 Elsevier Science Ltd. All rights reserved.
  • Publication Date: Oct 1999
  • Journal: Food Chemistry