This study investigated the effect of monosodium L-glutamate (MSG) on the saltiness and palatability of low-salt soup solutions. 584 participants tasted 0.3%, 0.6%, and 0.9% NaCl solutions with or without 0.3% MSG. Saltiness increased with NaCl concentration, and MSG significantly enhanced saltiness at the 0.3% NaCl level. Palatability was higher for solutions with MSG, especially the 0.3% NaCl + MSG solution, which was twice as palatable as the 0.3% NaCl solution without MSG. These results suggest that umami can compensate for palatability loss due to salt reduction, allowing for a reduction from 0.9% to 0.3% NaCl without compromising palatability.
