Abstract
In connection with flavor deterioration accompanied by food irradiation, the effect of γ-irradiation on sulfoxide amino acids in air free aqueous system was investigated. The major radiolysis products from S-n-propyl-L-cysteine sulfoxide (PCSO) were alanine, cysteic acid, dipropyl disulfide, etc.., and from S-allyl-L-cysteine sulfoxide (ACSO) were S-allyl-L-cysteine, cystine, cysteic acid, etc., which were isolated chromatographycally and identified by using IR and mass spectrometry. The sulfoxide in ACSO was more easily reduced to sulfide than that of in PCSO, and the bond of S-C (β-carbon in alanine moiety) in ACSO was difficult to cleave. These differences observed between PCSO and ACSO in the radiolysis products and their yields indicate that the radiolysis degradation is considerably influenced by the structure of alkyl group. From the experiments with N20 or KBr addition during irradiation, principal roles of the active species in irradiated water in the degradation processes were partly elucidated.
