Close-up of Botrytis sp. spores.
Photo by Ed Hellman, OSU
New Capabilities at ETS
ETS announces the availability of an improved method for measuring laccase activity. The current commercially available laccase assay does not function reliably in the presence of moderate SO2 levels (20-50 mg/L). The new ETS assay is not compromised by these levels of SO2 and enables detection of laccase on incoming juice samples, as well as throughout the wine making process.Significance of Laccase in wine
Laccase is a fungal enzyme primarily associated with rot on grapes caused by the grape pathogen Botrytis cinerea. Laccase can negatively impact wine by causing premature browning of bottled white wine and color degradation in red wine. This occurs when laccase converts phenolic compounds to quinones, and the quinones polymerize in the presence of oxygen. The polymerized quinones form pigmented compounds associated with laccase-induced browning and discoloration.
Consequences and Applications
Wines identified as containing laccase should be maintained in a reductive state to minimize browning and discoloration, and should not be blended with wines that do not contain laccase. Early detection of laccase enables winemakers to take appropriate actions to minimize the impact on the final wine product. This document is a compilation of information and views from various sources provided for the convenience of our clients. Information in this document is provided "as is" without warranty of any kind, either expressed or implied, including but not limited to the warranties of merchantability, fitness for a particular purpose and freedom from infringement. User assumes the entire risk as to the accuracy and the use of this document. This document may be copied and distributed subject to the following conditions: 1) All text must be copied without modification and all pages must be included; 2) All copies must contain ETS's copyright notice and any other notices provided therein; and 3) This document may not be distributed for profit. All trademarks are acknowledged. Copyright ETS Laboratories 2001-2013.