Effect of cooking method on the formation of 7-ketocholesterol in Atlantic hake (Merluccius hubbsi) and smooth weakfish (Cynoscion leiarchus) fillets.

Abstract
The levels of cholesterol and 7-ketocholesterol were measured in raw Atlantic hake (Merluccius hubbsi) and smooth weakfish (Cynoscion leiarchus) fillets and in fillets subjected to the following cooking methods: baking in an electric or microwave oven; baking, grilling or stewing in a steam-convection oven; simmering on a stove; electric grilling; and deep frying. The raw samples from both fishes exhibited significantly (p < 0.05) higher cholesterol levels (62.71 ± 6.06 mg/100 ge74.16 ± 3.96 mg/ 100 g) than the processed fillets. In all of the samples, 7-ketocholesterol was detected at significantly (p < 0.05) different levels depending on the cooking method and the type of fish. Steam cooking keeping the surface of the product moist produced small decrease in the cholesterol content (26.65%e29.96%) and a low level of 7-ketocholesterol in the samples (6.90 ± 0.21 mg/ge6.47 ± 0.28 mg/g). Baking in electric or steam-convection ovens at high temperatures and long times greatly reduced the cholesterol content (52.77%e65.08%), which was associated with a large increase in 7-ketocholesterol levels (11.54 ± 0.45 mg/ge13.94 ± 1.17 mg/g). These results indicate the necessity of revising the baking procedures for fish to increase the healthiness of food.
Description
Keywords
Fish, Cholesterol oxidation, Heat processing, Food service, Food protection
Citation
FREITAS, M. T. de et al. Effect of cooking method on the formation of 7-ketocholesterol in Atlantic hake (Merluccius hubbsi) and smooth weakfish (Cynoscion leiarchus) fillets. LWT - Food Science and Technology, v. 61, p. 1232, 2015. Disponível em: <http://www.sciencedirect.com/science/article/pii/S0023643815000638>. Acesso em: 02 fev. 2015.