Day 2: Wednesday, May 5th, 2021 – 11:10 am
Protein Instability in Wine: A Review
Protein instability can lead to the appearance of haze and deposits in wines, an aesthetic problem caused by the presence of grape proteins, mainly thaumatin-like proteins (TLPs) and chitinases that, under certain conditions, can become insoluble and aggregate into light-dispersing particles to make wines appear turbid. Since hazy wines are not saleable, this instability is generally prevented via bentonite fining, a treatment effective in removing the grape proteins responsible for haze formation, but with several drawbacks including the loss of wine loss, disposal costs, and removal of volatile compounds thus lowering the overall wine quality. As a consequence alternatives to bentonite are highly desirable, but for them to be successful, an in-depth understanding of the causes of protein hazing is required as this has the potential to lead to the development of novel, efficient, and environmentally sustainable winemaking processes to prevent haze from forming. In this talk an overview on the current understanding of the mechanism of haze formation will be given. In addition, a discussion on how the recent advances in the area allowed the elaboration of innovative strategies for protein stabilization of wines will be presented.