Effects of Grilling to 80℃ on the Chemical Composition of Pork Loin Chops and Some Observations on the UK National Food Survey Estimate of Fat Consumption

摘要

The physical and chemical composition of pork loin chops was investigated, examining the changes that occurred in (ⅰ) the whole chop, (ⅱ) the fat tissue and (ⅲ) the lean tissue by grilling to 80℃. Adjacent 25 mm thick chops, with backfat and rind attached, were cut from loins of 90 kg live weight pigs having a fat thickness (P_2) of 11 mm, representative of current UK production. One chop was analysed fresh by dissection and standard analytical techniques and the other after grilling. Weights of chop (including rind) before and after cooking were 210 and 136 g, respectively. The average weight loss for the whole chop was 35%; the weight loss from fat, 44%, being greater than that from lean, 34%, or rind, 27%, the latter accounting for 14% of the whole raw chop. When expressed conventionally, on a percentage basis, the fat content of the whole rindless chop increased from 22 to 23%, and the fat content of the lean increased from 5.5 to 9%. In absolute terms, based on an initial 100 g, the fat content in the whole chop reduced from 22 to 15 g, with a slight increase in the fat content of the lean, from 5.5 to 60 g. It is argued that the National Food Survey (NFS) approach of estimating fat consumption on the basis of the fat content of the raw product is flawed. The terms 'meat consumption' and fat consumption ' are misleading since they reflect amounts purchased rather than the amount of meat and fat actually consumed, making no allowance for fat lost during cooking or for subcutaneous fat removed by consumers before consumption. Actual fat consumption from cooked-meat and meat products, after allowing for a 25% fat loss during cooking and trimming of visible fat, is estimated at 10.3 g per person per day compared with the NFS estimate of 18.1g.