Disoium inosinate (E631), chemical formula C10H11N2Na2O8P, is the disodium salt of inosinic acid. It is a food additive often found in instant noodles, potato chips, and a variety of other snacks. It is used as a flavor enhancer, in synergy with monosodium glutamate (also known as MSG; the sodium salt of glutamic acid) to provide the umami taste.