The appetizing smells of broiled eel or yakitori skewers come from the aromatic substance , produced by an aminocarbonyl reaction on heating. In this reaction, the amino acids in soy sauce react with sugar, and with the sugar content of mirin and other ingredients. The aminocarbonyl reaction also helps to produce beautiful browning. Teriyaki and other dishes produced by the color and fragrance of soy sauce do actually make use of this reaction.