EFFECT OF END-POINT TEMPERATURE AND STORAGE TIME ON COLOR AND DENATURATION OF MYOGLOBIN IN BROILER THIGH MEAT

This study investigated the effect of end-point cooking temperature (EPT, 60, 66, 71, 77, and 82 C), sampling time (0 or 30 min), and storage time after cooking (0, 5, and 10 d) at 2 C on color values and percentage denatured myoglobin (PDM) of broiler thigh meat. As EPT increased, L* values, b* values, and PDM increased but a* values decreased. As storage time increased, L* and a* values decreased and PDM increased. Time of color measurement (immediately after cutting into the interior of the sample 0 vs 30 min after cutting) had a significant effect on L* and b* values. At 0 d storage 30 min sampling, a* values were redder than 0-min values from 60 through 71 C, no different at 77 C and redder at 0 than 30 min at 82 C EPT, suggesting that myoglobin is more susceptible to oxidative denaturation (reddish-brown pigment) at higher EPT after air and light exposure. At 5 d, 77 and 82 C a* values were less red after 30 min air and light exposure, suggesting that myoglobin was more susceptible to oxidative denaturation at higher EPT after storage. These results will help the meat processor identify and incorporate process factors that will lower the reddish-pink color defect in cooked poultry meat.