Efficacy of genetic parameter estimation of pork loin quality of crossbred commercial pigs using technological quality measurements of frozen and unfrozen product

Citation

Lei, H., Zhang, C., Li, C., Plastow, G.S., Bruce, H.L. (2018). Efficacy of genetic parameter estimation of pork loin quality of crossbred commercial pigs using technological quality measurements of frozen and unfrozen product. Canadian Journal of Animal Science, [online] 98(3), 453-462. http://dx.doi.org/10.1139/cjas-2017-0154

Plain language summary

It is a common practice in the meat industry to freeze meat for transportation and storage. However, freezing of meat may alter its quality characteristics. In this study, we measured meat quality traits including pork colour, pH, and drip loss on the loin muscle (longissimus dorsi) from the carcasses of 2027 crossbred commercial pigs when the muscles were either fresh or thawed after frozen storage. We also estimated how inheritable of the meat quality traits are at the stage of fresh or thawed after frozen, and how are the meat quality measures are correlated. The results showed that meat quality traits measured in fresh and after freezing and thawing were significantly (P<0.0001) different from each other, and intramuscular crude fat content exerted a large effect on the magnitude of change in meat color lightness (L*) and yellowness (b*). Meat quality measurements of fresh pork were moderately to highly heritable except for meat color yellowness (b*) and pH, with greater heritability estimates for meat color lightness (L*), pH, and drip loss when measured on fresh rather than on frozen-thawed samples. Based on the heritability and genetic correlation results, we concluded that whilst either fresh or frozen-thawed pork samples can be used for meat color lightness (L*), redness (a*), and yellowness (b*) measurements, pH and possibly drip loss should be measured on fresh pork samples rather than on those that have been frozen-thawed for genetic selection.

Abstract

Meat quality characteristics have been measured on fresh and previously frozen meat as part of genetic studies, but freezing of meat may alter its quality characteristics and, therefore, the relationships between genetic components and meat quality measurements. Pork color, pH, and drip loss measurements performed on longissimus dorsi from the carcasses of 2027 crossbred commercial pigs when either fresh or thawed after frozen storage were used to estimate genetic parameters using a bivariate animal model in ASReml. Meat quality traits measured before and after freezing and thawing were significantly (P < 0.0001) different from each other and intramuscular crude fat content exerted a large effect on the magnitude of change in L* (lightness) and b* (yellowness). Meat quality measurements of fresh pork were moderately to highly heritable except for b* and pH, with heritability estimates for L*, pH, and drip loss greater when measured on fresh rather than frozen-thawed samples. Considering heritability and genetic correlation results, we concluded that whilst either fresh or frozen-thawed pork samples can be used for fresh pork L*, a* (redness), and b* measurements, pH, and possibly drip loss should be measured in fresh pork samples rather than in those that have been frozen-thawed during genetic selection for fresh pork quality.

Publication date

2018-01-01

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