Effects of Potassium Carbonate on Quality Characteristics of Composite Starch‐wheat Noodles and its Mechanism

This study is to investigate the impact of potassium carbonate on quality characteristics of composite starch-wheat noodles (CSW). The results show that low level of potassium carbonate (0.2-0.4%) enhances the storage modulus (G') of dough and improves gel strength. The peak viscosity of composite flour is increased at low level of potassium carbonate that is confirmed by pasting properties analysis. Cooking loss of noodles decreases significantly due to the increasing hardness and resilience. The thermodynamic analysis indicates that Delta H decreases by increasing the potassium carbonate. The disulfide bonds (9.604-10.399 mu mol g(-1)), beta-sheet (26.9-31.4%), and starch order increases at low concentration of alkali. Based on the confocal laser scanning microscopic observation, the potassium carbonate (0.2-0.4%) causes a strong protein network in composite starch-wheat noodles and with gelatinized starch granules being well embedded in the network structure. It is observed that 0.4% potassium carbonate promotes protein aggregation and starch stabilization to improve the elasticity of composite starch-wheat noodles.