Phytase and vitamin E in the feed of growing pigs: 2. Influence on carcasscharacteristics, meat and fat quality

In four groups of six pigs the effect of dietary phytase (0 or 1200 PTU) an d/or alpha-tocopheryl acetate (0 or 200 mg) in barley-maize-based diets on various characteristics determining the quality of carcass, fresh meat (M. longissimus dorsi) and adipose tissue (back fat outer layer) was evaluated. Carcass composition was nor affected by dietary supplementations. The phyt ase supplementation resulted in a paler meat colour and lower pH 1-values ( p < 0.05) compared with the other groups. The alpha-tocopherol concentratio ns were higher (p < 0.01) and TEARS values were lower (p < 0.05) in the lon gissimus dorsi muscle of pigs that were fed on diets with added vitamin E. The percentage of mono-unsaturated fatty acids of the neutral lipid fractio n of longissimus dorsi was decreased (p < 0.05), while the saturated fatty acids of che complex lipid fraction in the phytase group were increased (p < 0.05) compared with the other groups. The content of alpha-tocopherol in the adipose tissue was increased (p < 0.001) due to the vitamin E supplemen tation. The oxidative stability of the back fat was reduced (p < 0.01) by t he addition of phytase and improved (p < 0.001) by dietary alpha-tocopherol supplementation. Vitamin E did not alter the fatty acid profile of fat in porcine muscle nor of back far outer layer, whereas dietary microbial phyta se addition increased the relative amount of saturated fatty acids (p < 0.0 5) in adipose tissue.