Studies on the influences of γ-ray irradiation upon food additives, (6)

The effect of γ-ray irradiation on monosodium glutamate (MSG) in aqueous solution and in ''kamaboko'' was investigated to evaluate the rate of decomposition of MSG and to elucidate the safety of the decomposed products, under the concentration of 106.9 mmol/l aqueous solution and 1% content of MSG in ''kamaboko''. In aqueous solution, MSG was decomposed by γ-ray irradiation, and G value was estimated to be 1.24. The decomposition of MSG resulted from deamination reaction was estimated to be 40% of the total decomposition. Glutamic acid content decreased as the dose of γ-ray increased in MSG-enriched ''kamaboko'', while it increased as the dose of γ-ray increased in MSG-free ''kamaboko''. Glutamic acid was liberated from the protein in ''kamaboko'', therefore the apparent decomposition rate of MSG in ''kamaboko'' was regarded as lower than actual. (author)