Appropriate dose of NaCl supplementation improves protein structures, microbial communities and extensibility of dough, and quality of traditional fermented dried noodles

Background and Objectives In the production process of Zhongjiang traditional fermented dried noodles (TFDNs), about 10% of NaCl is added; however, the underlying mechanisms of its effects remain unclear. Thus, this study aimed to investigate the impact of varying NaCl concentrations (6%–14%) on protein conformation, tensile and rheological properties, microbial communities in the dough, and quality of the dried noodles. Findings The results indicated that 6%–10% NaCl supplementation increased the ordered structures, disulfide bond contents, rheological parameters, the abundance of Pantoea and cumulative abundance of Mitochondria and Chloroplast in the dough, and reduced bacterial diversity and disordered structures; 8%–10% NaCl enhanced tensile properties of dough, cooking quality, and sensory attributes of noodles; cooked noodles with 10% NaCl had the best hardness, adhesiveness, springiness, and chewiness. However, excessive NaCl (12%–14%) did not confer these benefits. Furthermore, dough containing 6% NaCl exhibited excessive stickiness and reduced tensibility, rendering it unsuitable for making dried noodles. Conclusions The addition of 8%–10% NaCl improved protein structural properties and bacterial community in the dough and ultimately elevated the extensibility of the dough and the quality of TFDN. Significance and Novelty These findings reveal the potential mechanisms of NaCl in the processing of TFDN and lay a foundation for producing healthier TFDN with lower sodium in the future.