Seaweed Product Quality And Safety And Quality Analysis

Head space solid microextraction and GC-MS were employed to investigate the profiles of volatile compound from Porphyra haitanensis,Porphyra yezoensis and a green mutant of P.yezoensis and 66 volatile compounds were identified with 3 varieties containing 36,44 and 45.Among 66 volatile compounds,21 compounds were included in 3 varieties with high relative amount of 8-Heptadecene and Pentadecane,which might be responsible for the flavor of P.yezoensis.Volatile compounds with short chain aldehyde,alcohol and ketone constitute the characteristic flavor of P.yezoensis.The volatile components are similar between the wild-type and the green mutant of P.yezoensis,but the aldehydes and ketones are of greater abundance in P.yezoensis than those in P.haitanensis.The contents of 16 major free amino acids(FAA)in P.haitanensis,P.vezoensis and a green mutant of P.yezoensis were determined by reversed-phase high performance liquid chromatography with pre-column derivatization.The contents of the total FAA in P.yezoensis and the mutant of P.yezoensis was obviously higher than P.haitanensis,and the four FAA-alanine,arginine,glutamic acid and aspartic acid,of which the content are the most,may be the main factors.The content of total FAA in P.yezoensis which was affected by alanine and glutamic acid reduced with leaf age, and that proofed the contents of alanine and glutamie acid dominate the change of the total FAA content and the flavor of the early harvested seaweed is better than the latter.Solid phase extraction with reversed-phase high performance liquid chromatography was employed to sample survey the prometryn residue of dried laver in Nantong.The linear range of prometryn is 0.01 mg/kg～0.4 mg/kg,and the detection limit is 0.01 mg/kg,the fortified recovery ranged 82.41%～102.86%as well. The result have shown the prometryn residue of dried laver existing in trace amounts. in Nantong,and the residue in 16 companies' in Hai'an and Rudong is lower than the detection limit of "Positive List System" in Japan.