The influence of carcass backfat and intramuscular fat level on pork eating quality

To evaluate the contribution of fatness level towards pork eating quality, carcass and meat eating quality data were analysed from 721 pigs of three genotypes (with 0, 0.25 and 0.50 Duroc inclusion level). Animals (entire male and female) were reared from 30 to 90 kg liveweight on one of seven feeding regimens which involved combinations of diet formulation and feeding level, so as to produce carcasses of widely differing fatness levels. This experimental design produced coefficients of variation for classification P₂ backfat thickness of 21.11 (mean 11.59 mm, SE 0.093) and intramuscular fat (IMF) of 63.60 (mean 13.4 gkg^-1, SE 0.33). The treatments also produced considerable variation for eating quality as assessed by trained sensory panel (1-8 scale) and objectively (shear force) as shown by the following coefficients of variation: shear force 22.01% (mean 334N, SE 2.77), juiciness 16.12% (mean 4.95, SE 0.297), tenderness 19.65% (mean 5.06, SE 0.370), pork flavour 13.22% (mean 4.56, SE 0.225), abnormal flavour 34.46% (mean 2.02, SE 0.259) and overall acceptability 18.42% (mean 4.78, SE 0.328). Correlation coefficients between carcass fatness measurements and eating quality characteristics were calculated. Although shear force was significantly correlated with both classification P₂(r = -0.213) and IMF (r=- 0.189), taste panel tenderness was not significantly correlated to fatness level. Of the taste panel parameters evaluated, only juiciness showed a significant correlation (P < 0.05) with classification P₂(r=-0.086). None of the eating quality characteristics as evaluated by taste panel correlated significantly with IMF. These results do not support the belief that fatness level per se has a major influence on pork eating quality. (C) 2000 Society of Chemical Industry.