EFFECTS OF BLAST CHILLING AND POSTMORTEM CALCIUM-CHLORIDE INJECTION ON TENDERNESS OF PORK LONGISSIMUS MUSCLE

Two studies were conducted to evaluate the effects of blast chilling o f carcasses and injection with calcium chloride (CaCl2) at 24 h postmo rtem on Warner-Bratzler shear values (WBS) and moisture losses of pork longissimus muscles (LM). In a preliminary study, Exp. 1 was conducte d to determine whether the injection procedure using 100% water had an influence on WBS of pork LM. Injecting pork LM with water at 24 h pos tmortem had no effect on WBS (P = .64). In Exp. 2, 27 carcass sides we re assigned to 1) blast chilling for 1 h at 25 degrees C and then chil ling for 23 h at 1 degrees C or 2) standard chilling for 24 h at 1 deg rees C. At 24 h postmortem, the LM was removed from each side and divi ded into anterior (AL) and posterior (PL) halves. For each LM, the CaC l2 treatment was assigned randomly to either the AL or FL. Those recei ving CaCl2 were injected with a .3 M solution at 10% by weight. Muscle s then were stored for 3 d at 1 degrees C before 2.54-cm chops were re moved, cooked to an internal temperature of 70 degrees C, and allowed to cool for 2 h, then six 1.27-cm cores were taken and sheared. No dif ferences (P > .05) in purge or cooking loss were observed, but rapid c hilling reduced (P < .05) the combination of purge and cooking loss wi thout influencing WBS (P = .77). The injection of CaCl2 at 24 h postmo rtem lowered (P < .05) WBS of pork LM muscle. Therefore, the tendernes s of pork can be enhanced by injection of CaCl2.