Oxidative behavior of (+)-catechin in the presence of inactive dry yeasts: a comparison with sulfur dioxide, ascorbic acid and glutathione.

The YD preparation displayed a certain ability to protect polyphenols against browning. The antioxidant activity of YDs towards (+)-catechin appeared to be based on different mechanisms with respect to that of the other products tested: the insoluble portion of these preparations (cell wall residues) might have a non-negligible role, even if the ability of YDs to release compounds able to suppress oxidation cannot be rejected. Direct comparison of the different antioxidants led to interesting indications concerning their mechanism of action in wine-like solution, depending on their concentration and intrinsic characteristics. © 2017 Society of Chemical Industry.