WATER ACTIVITY AND TEMPERATURE EFFECTS ON NONENZYMIC BROWNING OF AMINO-ACIDS IN DRIED SQUID AND SIMULATED MODEL SYSTEM

At constant temperatures (5 to 45-degrees-C) browning rate patterns of 22 amino acids, induced during dehydration in presence of glucose and celite, pH 6.4, Aw 0.60 to 0.85, were classified into three types: 1. (lysine, histidine, and glycine) showed high rates over a broad a(w) range. 2. (Cysteine and methionine) had intermediate browning rates and a pattern of multiple maxima. 3. Amino acids (glutamine, valine and tryptophan) had low browning rates and showed a single sharp browning maximum. Squid mantle had broad browning maxima over the intermediate a(w) range resembling type 1, which comprised 75% of the total free amino acids in squid. Browning of squid was accelerated at greater-than-or-equal-to 23-degrees-C, with a(w) 0.60 to 0.90. Activation energy of the model systems was 10 to 35 kcal/mole, and Q10 were 1 to 8.