2011 年 57 巻 6 号 p. 432-436
The loss of vitamin B12 in round herring meats during various cooking treatments was evaluated. Although amounts of vitamin B12 were three times greater in the viscera (37.5±10.6 μg/100 g fresh weight) than in the meats, about 73% of total vitamin B12 found in the whole fish body (except for head and bones) were recovered in the meats (5.1±1.0 μg of vitamin B12). The vitamin B12 contents of the round herring's meats were significantly decreased up to ~62% during cooking by grilling, boiling, frying, steaming, and microwaving. There was, however, no loss of vitamin B12 during vacuum-packed pouch cooking. Model experiment using hydroxocobalamin suggest that loss of vitamin B12 is dependent on the degree of temperature and time used in conventional cooking, and is further affected by the concomitant ingredients of food. Retention of vitamin B12 was not dependent on vacuum or temperature (or both) used in the vacuum-packed pouch cooking.