Aim :Methodology : Results :Interpretation :

This study was conducted to investigate changes in physico-chemical characteristics of Hanwoo carcass according to different castration and slaughtering ages. Total 75 Hanwoo calves(average 4 months old) were randomly assigned to Control(bulls), Treatment , , , or (castrated on 4, 9, 12, and 16 months of age, respectively) and slaughtered at 7, 9, 12, 16, and 28 months of age. Moisture contents in M. Longissimus dorsi of both Hanwoo bulls and steers were decreased as the slaughtering age increased. Moisture contents in all steer groups were significantly(P < 0.05) lower(average 68.63%) than that in bulls(72.18%) at 28 months of age. Crude fat contents tended to increase as the slaughtering age increased. Crude fat contents in Treatment (castrated at 12 months of age) at 28 months of age were 10.24% which was the highest among all steer groups. Crude protein contents in M. Longissimus dorsi of Hanwoo bulls were around 23% regardless of slaughtering age. Water holding capacity(WHC) of both bulls and steers tended to increase as the animals aged. Steers showed rapid increase in WHC after 16 months of age and showed higher(78.39%) WHC than bulls(70.00%) at 28 months of age. Palmitic acid(C18 : 0) contents in Hanwoo bulls were increased as the slaughtering age increased(20.92 24.22%) whereas stearic acid(C18 : 0) contents were decreased(18.15 11.32%). Oleic acid(C18 : 1), a major unsaturated fatty acid, significantly(P < 0.05) increased(25.59 37.90%) when slaughtering age of Hanwoo increased. Changes in fatty acid composition in Hanwoo steers were similar to those in bulls except oleic acid contents were higher and stearic acid contents were lower than bulls at 28 months of age.