Determining the relationship between early postmortem loin quality attributes and aged loin quality attributes using meta-analyses techniques

Abstract

Meta-analyses techniques using 11 independent datasets were used to determine correlations between pork loin quality evaluated at 1-d postmortem and quality evaluated at 12- to 28-d postmortem. Datasets encompassed approximately 3,957 loins. The effects of aging on ventral loin surface quality were determined using a paired-T test. Ventral loin surfaces become 8% lighter (P < 0.0001), 44.5% redder (P < 0.0001), and 46% more yellow (P < 0.0001) during the aging period. Therefore, it is apparent that loin quality changes during postmortem aging. Because of this, it becomes necessary to determine the correlation between early and aged pork quality parameters. Pearson correlation coefficients within original datasets were calculated, and then sample-weighted mean correlations $\overline{r}$ and variances [Var(r)] were calculated across datasets. Early postmortem ventral instrumental lightness (L*) was moderately correlated with aged ventral L* $\overline{r}$ = 0.50), aged ventral visual color $\overline{r}$ = −0.38), aged chop face (freshly cut) L* $\overline{r}$ = 0.44), and aged chop face visual color $\overline{r}$ = −0.38). Early postmortem ventral instrumental redness (a*) was moderately correlated with aged ventral a* $\overline{r}$ = 0.49) and aged chop face a* $\overline{r}$ = 0.46). Early postmortem ventral visual color was moderately correlated with aged ventral L* $\overline{r}$ = −0.51), aged ventral color (⁠$\overline{r}$ = 0.50), aged chop face L* $\overline{r}$ = −0.43), and aged chop face visual color $\overline{r}$ = 0.43). However, no instrumental or visual color parameters were moderately or strongly correlated with instrumental tenderness or sensory panel ratings of tenderness and juiciness (|$\overline{r}$| ≤ 0.36). Early postmortem ventral visual marbling was moderately correlated with aged ventral marbling $\overline{r}$ = 0.63) and aged chop face visual marbling $\overline{r}$ = 0.56). Visual marbling was not (|$\overline{r}$| ≤ 0.12) correlated with instrumental tenderness or sensory panel ratings of tenderness and juiciness. Stepwise regression, using a holo-analysis approach, was used to determine the predictive ability of early postmortem ventral color, marbling, firmness, and pH on sensory panels ratings of tenderness (R² = 0.13), juiciness (R² = 0.09), and flavor (R² = 0.28). Early postmortem color and marbling are important pork quality traits in consumers purchasing decisions, but are poorly related to traits associated with eating experience. Still, they may be predicative of traits associated with purchasing intent.