Pork eating quality is mostly linked with the sensory taste measurements of texture, juiciness, flavour and tenderness, with overall acceptance and visual appearance also being important when panelists evaluate pork quality. What is clear is that these properties affect consumers’ acceptance and meat preferences and consequently their intention to purchase and willingness to pay. Therefore, improving pork overall eating quality is very important for the pork industry to enhance the competiveness of any pork market.

Visual appearance characteristics (i.e., colour, fat content, marbling) are intrinsic quality cues highly related with consumers' expectations of meat quality and their choice at the point of purchase.

Tenderness and juiciness are eating quality attributes that positively influence most consumers' preferences in pork. Texture problems such as excessive softness, pastiness or crust formation at the surface might also reduce consumer acceptance of the product. Flavour enjoyment is highly correlated with the overall eating experience of the meat. Multiple determinants shape consumer behavior toward meat and meat products. A better understanding of this complexity may help improve the competitiveness of the meat industry.

Many studies in pork revealed that the three principal potential sources of sensory differentiation in the modern meat chain, were diet and breed and these are often well controlled. The third aspect is associated with meat quality traits, like pH, colour and intramuscular fat (IMF) content. It appears that pH 5.8 to 6.0 gives the most acceptable flavour, juiciness and tenderness. IMF and the composition of the fatty acids are known to influence the sensory attributes related to texture, and particularly tenderness. Positive correlations (0.19 to 0.37) were found between IMF and flavour, tenderness and juiciness (Ngapo et al., 2012abc). Subjective colour was significantly correlated with most sensory traits as well (Huff-Lonergan et al., 2002).

Further, ageing time, cooking method and final core temperature also have important effects on pork sensory taste. Investigations based on a trained taste panel found that ageing of pork for 6 to 10 days has a positive effect on its eating quality compared to only 1 or 2 days. And the grilled pork loin with ageing > 7days was more tender, of stronger sweet taste and caramel flavour, and had a greater total number of sensory scores indicating a better sensory taste. A core temperature of 65 °C (149 °F) was preferable for a focus on flavour components, whereas 75 °C (167 °F) was recommended for discrimination of samples based on overall sensory properties (Bejerholm & Aaslyng, 2003).

Genetics, of course is one of the very important factors determining pork sensory and eating quality. A few candidate genes have been found to be associated with sensory taste. For example, a large panelist test on about 400 pork samples showed that the genes of AMPD1, FTO, ADIPOQ and LEPR had significant effects on many sensory taste scores including juiciness, tenderness, flavour and overall liking (Zhang et al., 2014). The alleles of FTO and LEPR, which were favorite for juiciness and overall liking, also had significant positive effects on lower shear force (more tender), better colour, better moisture, crude protein, IMF and cholesterol content (Li et al. 2010; Zhang et a., 2014). All these findings provide useful information for breeders to genetically improve pork sensory taste through genomic selection. Genesus Inc. can now utilize special custom SNP chips to assist in the genetic improvement of pork eating quality.

Genesus Inc. has conducted a carcass and pork quality program since 1998 and currently produces meat quality Estimated Breeding Values (EBVs) for marbling, pH and meat colour. Eating quality of pork has recently been further evaluated in a collaborative project with Livestock Gentec/ University of Alberta. A consumer panel evaluation of pork from Genesus crossbred commercial pigs showed that panelists favoured pork with higher pH and IMF. Pork quality is a high priority in the Genesus genetic improvement program, which consequently bring improvement for sensory taste as well.

As reported previously, we have tested the feasibility of using genomic markers to improve pork tenderness evaluation, which is one of the important measurements of pork eating quality. Incorporation of genomic technologies further strengthens the current evaluation of pH, marbling and meat colour, enhances the Genesus genetic improvement program for pork sensory taste, and supports the ultimate goal of increasing profitability for Genesus customers.

References

Bejerholm C & Aaslyng MD, 2003. The influence of cooking technique and core temperature on results of a sensory analysis of pork—Depending on the raw meat quality. Food Quality and Preference, 15: 19–30.

Huff-Lonergan E, et al., 2002. Correlations among selected pork quality traits. Journal of Animal Science, 80: 617–627.

Li X, et al., 2010. Investigation of porcine FABP3 and LEPR gene polymorphisms and mRNA expression for variation in intramuscular fat content. Molecular Biology Reports, 37: 3931–9.

Ngapo TM, et al., 2012a. Marbling and ageing — Part 1. Sensory quality of pork. Food Research International, 49: 396–405.

Ngapo TM, et al., 2012b. “Chilled” pork—Part I: Sensory and physico-chemical quality. Meat Science, 92: 330–337.

Ngapo TM, et al., 2012c. “Chilled” pork — Part II. Consumer perception of sensory quality. Meat Science, 92: 338–345.

Zhang C, et al., 2014. Associations between single nucleotide polymorphisms in 33 candidate genes and meat quality traits in commercial pigs. Animal Genetics, 45: 508–516.