Impact of fried foods on macronutrient intake, with special reference to fat and protein

Thermal treatment of protein is known to reduce protein quality and the destruction of certain amino acids. Fish and chips stili remain a popular food source in Britain. Little work has been done on the changes in protein quality during fish frying. The paper will present results obtained from the assessment of protein quality using net protein utilisation (NPU) in fried and steamed fish. Weanling male Sprague-Dawley rats were given stock diet (RM1 expanded, SDS Ltd., Witham, Essex) for 7 days at 30 days of age, groups of four were offered one of four diets that differed only in the type of fish and processing used. Diets contained 200g of fish protein, 550g carbohydrate (400g sucrose and 150g corn-meal), 50g mineral and vitamin mix and 200g fat/kg diet. The different fish species used were Cod and Plaice and the processing used was either steaming or frying. Although a fall in NPU was noted in fried fish compared to the steamed fish these changes in NPU could be reduced if the fish was covered with batter prior to frying.