100 Young Scholar Presentation: Effects of sex, sire line, and packaging method on the relationships among early postmortem loin quality and aged loin and pork chop quality characteristics

Abstract

Abstract A challenge in the pork industry is that packers assess pork loin quality at ~1d postmortem, while consumers assess quality after a period of postmortem aging. Rapid line speed necessitates rapid noninvasive assessment of quality by packers as indicators of aged (~14d) quality. However, it is unclear if this assessment is representative of quality observed by consumers at purchase. It is also unclear if correlations differ between barrows and gilts, sire lines, or packaging methods. Therefore, several studies were conducted to address these questions. Harsh et al. (doi.org/10.1093/jas/sky183) used meta-analyses techniques to establish correlations between early and aged pork loin quality. Data sets encompassed ~3,957 loins. Early instrumental and visual color were moderately correlated ( ≥ 0.38) with aged instrumental and visual color. No early quality parameters were correlated ( ≤ 0.36) with instrumental or sensory tenderness. With correlations between early and aged quality established, differences between factors of interest were tested. Correlations were compared using a Fisher’s z test. First, barrows and gilts were compared using a single sire line and raised in commercial conditions. Correlations between early and aged quality did not differ (P > 0.05) between barrows and gilts. Correlations between Pietrian- and Duroc-sired pigs were compared to determine correlation difference between sire lines using pigs from two different production focuses (meat quality vs. lean growth). Correlations between early ventral L* and aged chop L*, and early visual color and aged ventral L* differed (P ≤ 0.03) between Pietrain- and Duroc-sired pigs. However, the majority of correlations did not differ (P > 0.05) between sire lines. Correlations between packaging methods were compared by assigning boneless pork loins to one of two packaging methods, intact loins or case-ready chops. The correlations between early and aged quality traits did not differ (P > 0.05) between packaging methods. Overall, packers can use the same early quality characteristics to select for aged quality, regardless of sex, sire line or packaging method.