Nutritional influences on pork quality

This paper reviews the literature relating to the potential impact of swine nutrition on pork quality attributes. Supra-nutritional levels of vitamin E have been shown to increase muscle vitamin E content and reduce lipid oxidation; however, the impact on muscle color and water holding capacity has been variable. Selenium is also potentially involved in reducing lipid oxidation; there is no evidence, however, that supplying additional selenium above the requirement improves pork quality. Recent research has suggested that the feeding of high levels of vitamin D3 in the final 10 days prior to slaughter improves pork color and reduces drip loss; these results require validation. Feeding ingredients with relatively high levels of unsaturated fatty acids increases the degree of unsaturation of the fat tissue, decrease fat firmness, and can negatively impact fat quality. The potential to produce “healthier” pork by feeding ingredients rich in omega-3 fatty acids and to improve fat firmness by including conjugated linoleic acid in the diet is discussed. There is evidence that restricted feeding of growing-finishing pigs can negatively impact pork tenderness and juiciness. The marbling fat content of pork has been positively associated with eating quality and feeding protein-deficient diets in the final 5 weeks prior to slaughter has been shown to increase marbling. Australian research has suggested that supplementation of diets with magnesium aspartate for 5 days prior to slaughter reduces the incidence of PSE and improves muscle color and water holding capacity. A range of other dietary compounds has been investigated; however, there is limited evidence on which to judge their efficacy for improving pork quality under commercial conditions.