High-proline proteins in experimental hazy white wine produced from partially botrytized grapes

Proteomics and glycoproteomics of beer and wine

Beer and wine are fermented beverages that contain abundant proteins released from barley or grapes, and secreted from yeast. These proteins are associated with many quality attributes including turbidity, foamability, effervescence, flavour and colour. Many grape proteins and secreted yeast proteins are glycosylated, and barley proteins can be glycated under the high temperatures in the beer making process. The emergence of high-resolution mass spectrometry has allowed proteomic and glycoproteomic analyses of these complex mixtures of proteins towards understanding their role in determining beer and wine attributes. In this review, we summarise recent studies of proteomic and glycoproteomic analyses of beer and wine including their strategies for mass spectrometry (MS)-based identification, quantification and characterisation of the glyco/proteomes of fermented beverages to control product quality.

Laccases 2 & 3 as biomarkers of Botrytis cinerea infection in sweet white wines

Botrytized sweet wines are made with berries infected by the fungus Botrytis cinerea. The aim of this study was to identify biomarkers of B. cinerea infection in sweet wines with a focus on laccases which are exocellular oxidase enzymes produced by this fungus during fruit contamination. Total proteins from six commercial sweet wines, including three naturally botrytized wines and three non-botrytized wines were analysed by LC-QTOF-MS. Five laccases, namely laccase-1-BcLCC1, laccase-2-BcLCC2, laccase-3-BcLCC7, laccase-8-BcLCC8 and laccase-12-BcLCC12, were identified in both types of wine. Then, a targeted proteomic approach by LC-MRM was used to semi-quantify laccase-2-BcLCC2 and laccase-3-BcLCC7, in the six samples. LC-MRM targeted analysis of the two enzymes allowed the discrimination of botrytized versus non-botrytized sweet white wines.