Abstract
It is well known that guanylic acid enhances the taste of glutamic acid. We found that guanylic acid was produced by steam treating several vegetables (eggplant, tomato, carrot, Japanese radish, bunching onion and spinach). Evaluation panelists could organogenetically distinguish the addition of guanylic acid (at the concentration level in steamed vegetables of 10 mg/l) to carrot juice. It is suggested that guanylic acid in steamed vegetables contributes to the taste by enhancing the umami taste of glutamic acid. Oven roasting tomato concentrated the tasty compounds and also produced guanylic acid. The umami taste of roasted tomato would be much stronger than that of raw tomato, because of the synergistic effect between glutamic acid and guanylic acid with increasing concentration. The content of guanylic acid is suggested to be an important indicator for studying the taste of cooked vegetables.
