Effects of Dietary Glycine Betaine on Pork Quality in Different Muscle Types

This study was conducted to determine the effects of dietary glycine betaine on pork quality in different muscle types. A total of 80 female pigs ($Landrace{\times}Yorkshire{\times}Duroc$) were randomly allotted into one of four experimental diet groups. Each group of pigs were fed a commercial diet (Control) with 0.2 g glycine betaine (T1), 0.4 g glycine betaine (T2) and 0.6 g% glycine betaine (T3)/kg for 40 days. pH of belly was significantly higher in the control than dietary glycine betaine groups at 13 days of storage, whereas pH of picnic shoulder and ham were significantly lower in control than glycine betaine groups. At 13 days of storage, redness (a*) of belly was significantly higher in control than dietary glycine betaine groups, whereas picnic shoulder and ham were significantly higher in glycine betaine groups than in the control. Water-holding capacities (WHC) of all muscle samples were significantly higher in the control than glycine betaine groups until 5 days of storage. Sarcomere length was significantly longer in the control than glycine betaine groups. The thiobarbituric acid reactive substances (TBARS) value of belly was much higher than other muscle types at 13 days of storage. In fatty acid composition, dietary glycine betaine increased the ratio of saturated fatty acids (SFA) and decreased unsaturated fatty acids (USFA) in loins.