Study of the mechanisms of the enzymatic oxidation of the grape must and some possible alternative systems to sulfur dioxide for its prevention.

Identifier:  TDX:4165

Handle: https://hdl.handle.net/20.500.11797/TDX4165

Authors:  Giménez Gil, Pol

Abstract:
polymers remain dissolved in the wine (browning). In contrast, in the case of red wines, oxidations reach higher levels of polymerization in which their molecular mass increases to the point of instability within the matrix, which ultimately results in precipitation (oxydasic haze). Based on this hypothesis, we have studied the mechanisms of enzymatic oxidation in the must caused by Botrytis cinerea laccase, its involvement in the development of brown color, as well as what are the most effective methods to reduce its effects. A synthetic model has been developed to study the mechanism of browning caused by the laccase activity of Botrytis cinerea. On the other hand, a model has been developed using white grape must to study the mechanism of browning in must from healthy grapes with or without supplementation of Botrytis cinerea laccase to reproduce what would occur with rotting grapes. This has enabled a study to be carried out on biotechnology tools to reduce the use of sulphur dioxide and prevent enzymatic browning. Finally, the enzymatic oxidation mechanisms of anthocyanins present in red must have been studied.