The effect of sex, carcass mass, back fat thickness and lean meat content on pork ham and loin characteristics

Abstract. This study was designed to determine the ratio of ham and loin in half-carcasses and the tissue composition of these cuts. The research material consisted of 140 pig carcasses. The experimental materials were derived from the Polish commercial population of fattener pigs. Genetic material representing the most commonly slaughtered fatteners in Poland. Fatteners for the study came from several suppliers. All fatteners were kept in similar farms complying with principles of animal welfare. The right half-carcasses were divided into different groups, regardless of sex, half-carcass mass, back fat thickness and lean meat content class. Ham and loin obtained from carcasses were subjected to a detailed dissection, and the percentage of ham and loin in the carcass and the overall percentage of of the cuts in relation to the entire half-carcass were calculated. Gilts were characterized by a higher content of ham in half-carcasses than barrows (P  ≤ 0.01). The increase in back fat thickness reduced the content of ham in half-carcasses and increased the content of loin (P ≤ 0.01). A similar trend was shown for the lean meat content class parameter. Additionally, interaction (P  ≤ 0.01) between back fat thickness and meat content with respect to the percentage content of loin in carcasses was noted. Gilts were characterised by about a 1.38 % higher proportion of muscles in the ham (P  ≤ 0.05) and a 0.47 % lower proportion of intermuscular fat (P  ≤ 0.01). An average increase of five point in back fat thickness increases the amount of subcutaneous fat with skin (P  ≤ 0.01) and intermuscular fat (P  ≤ 0.01) and reduces muscle (P  ≤ 0.01) and bone (P  ≤ 0.05 and P  ≤ 0.01) levels. The interaction of percentage content of muscles in ham was observed (P = 0.04). The meat content class of carcasses did not only affect the level of bones in ham. It was confirmed that sex affected all the analysed dissection elements of the loin. Back fat thickness and meat content classes were present in almost identical amounts in loin tissues (P  ≤ 0.05 and P  ≤ 0.01). Half-carcass mass showed a strong negative correlation with bone content in ham and loin (r = −0.35 and r = −0.21, respectively). Back fat thickness and meat content strongly and inversely correlated with the content of ham and loin in half-carcasses (r = −0.41 and r = 0.59 for back fat thickness; r = 0.66 and r = −0.57 for lean meat content). Close and inverse correlations of back fat thickness and lean meat content were observed with regard to their content in ham and loin (P  ≤ 0.01).