Vinegar Functions on Health: Constituents, Sources, and Formation Mechanisms

Vinegars are one of only a few acidic condiments throughout the world. Vinegars can mainly be considered grain vinegars and fruit vinegars, according to the raw materials used. Both grain vinegars and fruit vinegars, which are fermented by traditional methods, possess a variety of physiological functions, such as antibacteria, anti-infection, antioxidation, blood glucose control, lipid metabolism regulation, weight loss, and anticancer activities. The antibacteria and anti-infection abilities of vinegars are mainly due to the presence of organic acids, polyphenols, and melanoidins. The polyphenols and melanoidins also provide the antioxidant abilities of vinegars, which are produced from the raw materials and fermentation processes, respectively. The blood glucose control, lipid metabolism regulation, and weight loss capabilities from vinegars are mainly due to acetic acid. Besides caffeoylsophorose (inhibits disaccharidase) and ligustrazine (improves blood circulation), other functional ingredients present in vinegars provide certain health benefits as well. Regarding anticancer activities, several grain vinegars strongly inhibit the growth of some cancer cells in vivo or in vitro, but related functional ingredients remain largely unknown, except tryptophol in Japanese black soybean vinegar. Considering the discovering of various functional ingredients and clarifying their mechanisms, some vinegars could be functional foods or even medicines, depending on a number of proofs that demonstrate these constituents can cure chronic diseases such as diabetes or cardiovascular problems.