Thermal Behavior of Basic Amino Acid Residues of Muscle Protein during the Incubation of Fish and Poultry Minces

The thermal behavior of basic amino acid residues of muscle proteins during incubating fish and poultry minces was investigated. For the transglutaminase-free muscle minces from Alaska pollack, Pacific mackerel, and horse mackerel, their acidic dye-binding ability was increased upon their incubation at 30°C for 5 h and simultaneously, the rise of pH was suppressed in their titration with 0.1N NaOH. The increment of the dye-binding ability and the suppression of pH rise, however, were not observed for the minces from beef, chicken, and pork. Based on the above results, it was presumed that the basic amino acid residues are easy-to-expose on the molecular surface of fish proteins during the incubation but hard-to-expose in the case of poultry proteins.