Physicochemical Meat Quality and Sensory Property of Holstein Steer Beef Produced by Different Fattening Periods

This study was performed to investigate the physico-chemical properties of Holstein steer beef loin (M. longissimus dorsi) and top round (M. semimembranosus) from 18, 21 and 24-mon old. The loin and top round muscles from the 24-mon group had higher intramuscular fat content (%) than the other groups (p<0.05); however, the protein content was not significantly different among the 3 groups (p>0.05). With regard to meat color (CIE), the lightness ($L^*$), redness ($a^*$) and yellowness ($b^*$) values of the loin were significantly higher for the 21- and 24-mon groups, and those of the top round were significantly higher for the 21-mon group than the same cuts in the other groups. The Warner-Bratzler shear force was the lowest at 24 mon for both the loin and top round muscles (3.69 kg); however, the water holding capacity was significantly higher for loin muscles from the 21-mon group (54.53%, p<0.05). The loin muscles from the 24-mon group contained significantly higher levels of monounsaturated fatty acid and significantly lower levels of saturated fatty acid than those in the other groups (p<0.05). The tenderness, juiciness, flavor-likeness and the overall-likeness scores were significantly higher for beef from the 21- and 24-mon groups than that from the 18-mon group. The results of this study indicate that both the slaughtering age and muscle type significantly affect meat quality. Therefore, fattening the beef for more than 4 mon during the late fattening stage would be advantageous for the meat quality of Holstein steers.