Free thiol groups in the albumin/globulin extracts of doughs. The number indicates the dough systems described in Figure 1. Dough 1, yeast-fermented dough at 30 °C for 1 h; 2, yeast-fermented dough at 30 °C for 17 h; 3, yeast-fermented dough at 4 °C for 17 h; 4, yeast-fermented dough with glutathione at 30 °C for 1 h; 5, yeast-fermented dough with glutathione at 30 °C for 17 h; 6, chemically acidified dough, pH 3.5, at 30 °C for 17 h; 7, wheat sourdough at 30 °C for 17 h; 8, chemically acidified dough, pH 3.5, with glutathione at 30 °C for 17 h; F, wheat flour. Bars that do not share a common superscript differ significantly (p < 0.05, one-way ANOVA with Tukey’s honest significance test (HSD) analysis).