Mechanism and inhibition of development of rancid off odor in cooked fish meats during storage at 5゜C

Research Project

Project/Area Number	60560214
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Fisheries chemistry
Research Institution	Tokyo University of Fisheries
Principal Investigator	KOIZUMI Chiaki Tokyo University of Fisheries, Professor, 水産学部, 教授 (80017045)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥1,500,000 (Direct Cost: ¥1,500,000) Fiscal Year 1986: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1985: ¥1,000,000 (Direct Cost: ¥1,000,000)
Keywords	Rancid off odor / Lipid oxidation / Cooked fish meat / TBA value / Heme pigment / 非heme鉄
Research Abstract	1. To investigate factors affecting development of rancid off odor in cooked fish meats during storage in a refrigerator of 5゜C, rates of lipid oxidation of the cooked meats of various species of fish were compared each othr using TBA test. As a result, rates of increases in TBA values of cooked white muscles of fish examined were as follows ; saury>mackerel>sardine>horse mackerel>flying fish>sablefish>halibut>dusky sole. 2. Influences of water-extract of mackerel meat on the lipid oxidation of cooked water-extracted mackerel meat were examined. The results obtained indicated that the dialysate of water-extract showed much higher activity to cause rancidity of water-extracted mackerel meat than the diffusate. 3. Influences of Mb, iron ions ( <Fe^(2+)> , <Fe^(3+)> ), EDTA, nitrite and ascorbate on the rates of increases in TBA values of cooked water-extracted mackerel meat were examined. The results obtained were as follows ; (1) Mb, <Fe^(2+)> and <Fe^(3+)> accelerated increases in TBA values of the meat, (2) EDTA inhibited completely the increases in TBA values of the meat accelerated with added <Fe^(2+)> and <Fe^(3+)> , but did not influence those accelerated with added Mb, (3) Nitrite and ascorbate inhibited increases in TBA values of the meat accelerated with added Mb. 4. Examinations similar to those mentioned above were carried out on cooked unextracted mackerel meats. The results obtained showed that the increases in TBA values of the meat during storage were inhibited completely with added either nitrite and ascorbate or nitrite, ascorbate and EDTA and to a large extent with added EDTA alone. From these results, not only heme pigment but also nonheme iron in fish meat was suspected of catalysts of lipid oxidation responsible for development of rancid off odor after cooking.