Effect of Dietary Glycine Betaine on Pork Qualities During Storage

A total of 80 pigs were used to investigate the effect of dietary glycine betaine( N,N,N -trimethylglycine) onpork quality during cold storage. About 70 kg pigs were randomly alloted into one of four experimental dietgroups(0%, 0.2%, 0.4% and 0.6% glycine betaine). Pigs were slaughtered at approximately 110 kg liveweight, and pH, color(CIE L* a* b*), shear force, sarcomere length, lipid oxidation and composition of fat-ty acid were measured in pork loin for 13 days of cold storage. The concentration of glycine betaine inpork loin was significantly increased(P < 0.05) with incr easing of glycine betaine level in diet. Pork loinsfrom dietary betaine groups showed significantly higher muscle pH and lower CIE b* values compared tocontrol group after 13 days of storage. There were significant differences in shear force values among porkloins from diet groups at 24 hrs postmortem. However, pork loins from control diet showed longer sarco-mere length than those of dietary betaine groups. Dietar y glycine betaine increased the ratio of saturated fattyacids and decreased unsaturated fatty acids in pork loins. Especially the ratios of linoleic and myristic acid were de-creased with increasing dietary betaine level. However, d ietary glycine betaine did not affect lipid oxidation(TBARS) and sensory evaluation during cold storage.