Sulfhydryl oxidase enhances the effects of ascorbic acid in wheat dough

Various enzyme families such as sulfhydryl oxidase have been successfully applied to bread production although their mechanism of action has not been fully described yet. In this study, we investigated the effects of the recently characterized fungal sulfhydryl oxidase AoSOX1 in fresh and frozen dough alone and in combination with ascorbic acid. The addition of AoSOX1 to an additive-free dough resulted in a weaker and more extensible dough while opposite effects were detected in the presence of ascorbic acid. The hardening of the doughs registered upon the combined use of AoSOX1 and ascorbic acid was dependent on the amount of enzyme used and not on the amount of ascorbic acid. The ability of the sulfhydryl oxidase to enhance the effects of the ascorbic acid system suggests their combined use as a valuable tool to stabilize the structure of fresh and frozen dough.

► Fungal AoSOX1 was tested in fresh and frozen dough alone and with ascorbic acid.
► AoSOX1 reduced strength and increased extensibility of additive-free doughs.
► AoSOX1 increased strength and reduced extensibility of doughs with ascorbic acid.
► AoSOX1 hardened doughs containing ascorbic acid in a dose-dependent manner.
► AoSOX1 could be used with ascorbic acid to further improve fresh and frozen doughs.