In vitro evaluation of physiological activity of vinegar produced from barley-, sweet potato-, and rice-shochu post-distillation slurry.

Vinegar was produced from barley-, sweet potato-, and rice-shochu post-distillation slurry using jar fermentor within 19 hrs. All the vinegars showed radical-scavenging activity, angiotensin I converting enzyme (ACE) inhibition and advanced glycation endproducts (AGE) inhibition in vitro. The radical-scavenging activity of the vinegar produced from sweet potato-shochu post-distillation slurry was higher than that of other two kinds of vinegar on the organic matter basis. The ACE inhibitory activities of all the vinegars were higher than that of each post-distillation slurry. The main components that showed ACE inhibitory activity would be peptides, and their content increased during acetic acid fermentation. Regarding AGE inhibition, only rice-shochu post-distillation slurry did not show such activity, but the other two post-distillation slurries and all the vinegars showed clear inhibitory activity. The activity appeared to depend on the concentration of amino groups except for sweet potato-shochu post-distillation slurry and the vinegar produced from it.