PORK CARCASS COMPOSITION - I - INTERRELATIONSHIPS OF COMPOSITIONAL END-POINTS

Thirty pork carcasses were used to evaluate the interrelationships bet ween compositional end points and the accuracy of predicting various e nd points from one another. Right sides were fabricated into Boston bu tt, picnic, anterior belly, posterior belly, anterior loin, posterior loin, and ham. Carcass composition was determined on the right side us ing physical dissection and chemical analyses of soft tissue. Left sid es were ground (whole-side grind). Linear measures and chemical compos ition were made on left sides. Using dissectable components, high (r > .85) correlations occurred between percentage of fat-free lean and pe rcentage of lipid, percentage of dissectable fat, and lipid in the who le-side grind; between weights of dissectable lean and fat-free lean; and between weights of lipid in the whole-side grind and lipid, dissec table fat, and dissectible lean. Dissectable lean percentage and fat ( percentage and weight) could be predicted using weight of lipid, weigh t of fat-free lean, and side weight. Any physical measure could be acc urately estimated fl om any compositional end point (r(2) = .79 to .93 ). Regression equations using 10th-rib linear measures and hot carcass weights predicted compositional end points with R2 greater than or eq ual to .80, with the exception of dissectable lean (R-2 = .56).