The effect of cooking on the chemical composition of meat products with special reference to fat loss

Abstract

The chemical composition and energy content of four product categories (sausages, restructured steaks, burgers and minced beef) were determined before and after cooking. Two cooking methods were used for each product category: sausages and burgers were fried or grilled, restructured steaks were grilled or cooked in an oven whilst mince was either boiled or lightly fried and then boiled to simulate domestic practice. Based on an initial 100 g of product and excluding the low fat products included in the survey, the average weights after cooking were 78, 73, 72 and 70 g for the sausages, restructured steaks, burgers and minced beef, respectively; average fat contents before and after cooking were 22 and 17 g for the sausages, 17 and 14 g for the restructured steaks, 25 and 16 g for the beef burgers, and 19 and 7 g for the mince; and average energy contents before and after cooking were 1215 and 1016 kJ for the sausages, 958 and 815 kJ for the restructured steaks, 1244 and 906 kJ for the burgers and 1009 and 544 kJ for the mince. For a given product type, cooking method was relatively unimportant; the cooking loss, fat loss and energy content of the cooked product being more dependent on product formulation and manufacturing process. The survey included a low fat sausage, a low fat burger, a lean mince and an extra lean mince with fat contents of 8.7, 7.5, 12.4 and 5.2%, respectively. Overall weight losses during cooking were similar to standard products, though low fat products lost proportionally more water and less fat. Frying resulted in a slight gain in fat content for the low fat sausages and burgers, based on an initial 100 g of product, though fried low fat products still had lower fat and energy contents than standard products. It is argued that national consumption figures should take into account the losses that occur during cooking to avoid overestimating fat and energy intake levels.