Effects of nutritional modifications on the water-holding capacity of fresh pork: a review

Although genetics and preslaughter handling and management have the greatest impact on pork quality - especially water-holding capacity (WHC) - modifications to swine diets may offset the negative effects of genotype and/or pig handling on pork quality or improve quality attributes of pork from pigs with the genetic potential for good quality. There is little evidence that pork WHC is altered by the lysine or protein level (and source), cereal grain, or fat source used in growing-finishing diets. Yet, recent research indicates that feeding low-starch, high-fibre, high-fat, glycogen-reducing diets effectively improves the WHC of pork. Moreover, meta-analysis of the available information indicated that including 100, 200, or 400+ mg of alpha-tochopherol per kilogram of diet reduced pork drip losses by 10.1%, 30.5%, and 25.9%, respectively, whereas supplementing swine diets with magnesium for 1-2 days, 3-4 days, or 5-7 days reduced drip losses by 23.1%, 13.7%, or 15.9%, respectively. Some swine nutritionists have advocated the removal of vitamins and trace minerals from finishing diets; however, deletion of vitamin/trace mineral premixes actually reduced the WHC of pork, whereas drip losses were reduced by elevating the dietary inclusion levels of vitamins and trace minerals 150-250% of the recommended levels. Additionally, there is no evidence that feeding pigs ractopamine hydrochloride or injections of porcine somatotropin affect pork WHC. There may not be a single 'silver bullet' that will remedy poor quality genetics or poor animal management, but improvements in pork WHC can be achieved with some modifications to swine finishing diets.