Quality characteristics of fresh noodles with low-sodium salt and the underlying mechanisms.

Influence of low-sodium salt on water mobility, chemical interactions, and structural changes in noodles was investigated to explore the underlying mechanisms of noodle quality changes, and the results were in comparison with those of NaCl and KCl. Low-sodium salt increased the cooking loss, hardness, chewiness, maximum tensile strength, and tensile fracture distance of noodles. Low-sodium salt enhanced the interaction of water and non-aqueous components in noodles by reducing water mobility. Besides, chemical interaction test showed that low-sodium salt induced the oxidation of some free SH groups to form SS bonds, and strengthened the hydrophobic interaction and hydrogen bonds of gluten. Fluorescence spectra revealed that low-sodium salt changed the microenvironment of gluten molecules. Scanning electron microscopy (SEM) images showed that low-sodium salt noodles presented a more continuous and compact microstructure. Among the three kinds of salted noodles, some qualities of low-sodium salt noodles were equivalent to or slightly worse than those of NaCl noodles, but higher than those of KCl noodles. Hence, replacing part of NaCl with KCl in noodle products is an effective method to reduce sodium content.