Abstract:In order to study the effect of sulfhydryl groups(SH) and disulphide bonds (SS) on the rheological properties of dough, gluten samples, first treated with sodium sulfite of different concentrations, were added into flour to get flour samples with different SH and SS contents. The kneading and tensile properties of dough were investigated and the correlation between the parameters was also analyzed. The results showed that, as the content of SS bonds decreased obviously, there were marked drops in water absorption rate, farinograph quality number, time of dough formation and dough steadiness of mixed flour dough samples. There were significant differences among various samples (P<0.05). As to extensibility, it was found that the sample B owned the best tensile property. The tensile properties of other samples in turn became poor with the increasing of Na2SO3 concentration added into gluten protein. The maximum tensile resistance and ductility of sample H were the worst but were still better than the control group. Based on the Pearson correlation analysis, there was obvious relationship between SS bonds content of flour samples and farinograph and tensile parameters. SS bonds was correlated strongly with water absorption rate, farinograph quality number, time of dough formation and dough steadiness, and the maximum tensile resistance, respectively. It had a negative correlation with the weakening grade. Additionally, it was correlated positively with ductility and stretch curve area. Hence, the above indices were effected strongly by SS bonds rather than free SH or the ratio of free SH/SS. To sum up, this study can provide theoretical basis for revealing the effects of gluten on processing properties of wheat flour and noodle and breeding specific wheat varieties.