Predicting pork loin chop yield using carcass and loin characteristics

Abstract

The objective was to determine the predictive ability of carcass length for the number of equal-thickness chops obtained from a boneless pork loin. Longer pork carcasses are assumed to yield longer loins and, therefore, an increased number of chops. Loins were collected from pigs (1,238 total) raised under commercial conditions and marketed when the mean pig weight in a pen reached 138 kg. Pigs were slaughtered over 7 wk in a commercial facility. Carcass length was measured at 1 d postmortem on the left side of each carcass from the anterior edge of the symphysis pubis bone to the anterior edge of the first rib. Carcasses were fabricated, and boneless loins (North American Meat Processors number 414) were vacuum packaged and transported to the University of Illinois Meat Science Laboratory. Loins were stored at 4°C for 14 d. At the end of the aging period, loins were weighed, measured for stretched length (stretched to maximum length without distortion) and compressed length (compressed to minimum length without distortion), and sliced into 2.54-cm-thick chops. Boneless chops were counted and weighed. Carcass length ranged from a minimum of 78.2 cm to a maximum of 96.5 cm and the number of boneless chops ranged from a minimum of 13 to a maximum of 20 chops. Data were analyzed using the regression procedure of SAS. The dependent variable was the number of boneless chops. Coefficient of determination () was calculated for carcass length, boneless loin weight, compressed loin length, and stretched loin length. Carcass length explained 15% ( < 0.0001) of the variation in the number of loin chops. Loin weight explained 33% ( < 0.0001) of the variation in the number of loin chops. Compressed loin length and stretched loin length explained 28 and 8% ( < 0.0001), respectively, of the variation in the number of loin chops. Multiple linear regression was used to determine a predictive equation for the number of loin chops using the stepwise selection option of all independent variables. The combination of boneless loin weight, compressed loin length, 10th-rib carcass fat depth, and carcass length explained 45% of the variation ( < 0.0001; C(p) = 16.76) in the number of loin chops using a required statistic at the SLENTRY and SLSTAY level = 0.15. Overall, carcass length is a poor predictor of the number of equal-thickness loin chops that can be derived from a boneless pork loin.

Microbiability of meat quality and carcass composition traits in swine

“…Results from Man-Whitney tests showed that alpha diversity at all stages were different ( P < 0.001) to each other. This was in accordance with similar studies in pigs and other organisms (Frese et al, 2015; Guevarra et al, 2019); Lu et al, 2018). The increase in alpha diversity with age was similar to what previously found by different authors (Chen et al, 2017; Kim et al, 2011; Looft and Allen, 2012; Thompson et al, 2008).…”

“…No change in genomic heritability were observed at weaning. The decrease in heritability for FD was similar to what found by Lu et al (2018) for similar traits. He et al (2016) also reported the significant contribution of microbiome in porcine fatness.…”

“…This change caused the microbial shift after weaning transition (Kim and Isaacson, 2015) and microbial succession continues until microbiota composition reaches to climax community (Chen et al, 2017) which consists of microbes that are stable in composition. Further higher granularity results on the characterization of the microbial composition in the individuals of the current study can be found in Lu et al (2018).…”

“…Rectal swabs were collected from all pigs at three stages: weaning ( Wean ), 15 weeks post weaning ( Mid-test ; average 118.2 ± 1.18 days), and off-test. Four pigs from each pen were selected as detailed by Wilson et al (2016) and their rectal swabs were used for subsequent microbial sequencing. There were 1,205, 1,295 and 1,273 samples for weaning, Mid-test and Off-test respectively.…”

“…Phenotypic data collection was done as described by Wilson et al (2016). Meat quality traits (intramuscular fat content ( IMF ), Minolta a* ( MINA ), Minolta b* ( MINB ), minolta L* ( MINL ), ultimate pH ( PH ), subjective color score ( SCOL ), subjective marbling score ( SMARB ), subjective firmness score ( SFIRM ), shearing force ( SSF )) and carcass composition traits (Belly weight ( BEL ), ham weight ( HAM ), loin weight ( LOIN ), fat depth ( FD ), loin depth ( LD ) and carcass average daily gain ( CADG )) were used for the current analysis.…”