Comparison of extractive components in muscle and liver of three Loliginidae squids with those of one Ommastrephidae species

Extractive components were determined for the mantle muscle and liver of three species of Loliginidae squid, Sepioteuthis lessoniana, Loligo bleekeri, and L. edulis, and one species of Ommastrephidae, Todarodes pacificus, as a control. Total free amino acid levels and the major free amino acids in muscle, taurine, proline, glycine, alanine, and arginine, were significantly higher in Loliginidae squids than in T. pacificus. The main nucleotide was adenosine 5'-monophosphate, which did not differ significantly between species. Malate was the organic acid found in muscle in highest concentrations. The muscle of these species contained a large amount of trimethylamine oxide. A large amount of glycine betaine was also detected in the muscle, but showed no large species difference. From these results, the muscle of Loliginidae species is considered to have a much sweeter taste than that of T. pacificus. Compared with muscle, squid liver was characteristic with high contents of taurine, glutamate, bitter amino acids, succinate, propionate, trimethylamine, and glycine betaine, and with low contents of sweet amino acids, arginine, nucleotides, malate, and trimethylamine oxide. These results suggest that squid liver is characterized by a complicated taste containing umami, bitterness, sourness, fishy flavor, and less sweetness.