Author
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LYON, BRENDA |
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LYON, CLYDE |
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Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/2/2002 Publication Date: 12/10/2002 Citation: Lyon, B.G., Lyon, C.E. 2002. Color of uncooked and cooked broiler leg quarters associated with chilling temperature and holding time. Poultry Science. 81:1916-1920. Interpretive Summary: Color appearance of processed poultry can be a problem in bone-in dark meat parts that must be chilled and stored. Slow chilling rates can cause cell disruptions and blood migration from the bone and result in discoloration of raw or cooked tissue. In this study, leg quarters were held at five temperatures (**4, 0, **3, **12, or **18 C) for seven days. At Day 7, one group of samples (A) at each temperature was evaluated for color. Another group (B) of samples at each temperature at Day 7 was stored at **18 C for seven additional days to represent steps of cooling, freezing, thawing and cooking. Instrumental color measurements of lightness, redness, and yellowness were determined on uncooked and cooked leg quarters from both groups. Color measurements were taken on surfaces of thawed, uncooked parts, on surfaces of cooked parts, and of cooked meat adjacent to the thigh bone. Raw surface color of Group A samples at 3 C (26 F) was redder than samples held at **18 C (0 F) (redness value 8.91 vs 5.04) but these differences due to chill temperature were not evident in samples that had been further stored at **18C, then thawed, cooked and evaluated for color. Cooked meat color near the bone was redder when parts were chill-stored at 0 or **3 C, then frozen at **18 C before cooking and evaluating. Higher internal cooking temperatures lessened the redness of the tissue. These results will aid processors and retailers in optimizing temperatures for storing and handling poultry dark meat parts. Technical Abstract: Color appearance of processed poultry chilled at temperatures ranging from **4.5 to **18 C is of interest to consumers and processors. Discoloration of raw or cooked tissue can occur from cell disruptions and blood migration caused by slow chilling rates. CIE L*, a*, and b* color values (measuring lightness, redness, and yellowness, respectively) were determined on uncooked and cooked leg quarters chilled at **4, 0, **3, **12, or **18 C Two groups of leg quarters were held in chambers set at test temperatures for seven days. At Day 7, Group A samples were evaluated for color. At Day 7, Group B samples were moved to a -18 C chamber for seven additional days at which time they were thawed and cooked. Group B represented steps of cooling, freezing, thawing and cooking. Color was measured on surfaces of thawed, uncooked parts (UCS), on surfaces of parts cooked to 75 or 85 C internal temperature (CS), and on cooked meat (CM) adjacent to the femur. UCS samples at **3 C were significantly redder (a*value, 8.91) than sample held at **18 C (a*, 5.04). The a* values of Group A-CS showed a significant (P**.05) interaction between chill temperature storage and internal temperature (IT) of cooked samples. Samples at 75 C IT had higher a*values (redder). CM samples held at +4 and 0 C were significantly lighter (higher L* values). Surface color of UCS and CS samples from Group A held at -18 C showed no differences due to initial chill temperature. The a*values of CM showed a significant interaction effect due to chill temperature of storage and IT. Generally, 75 C IT samples were redder (higher a*values). Surface color of leg quarters was not influenced by chilling at **4.5 to **18 C for seven days and then at -18 C for seven days. CM was affected by a combination of chill temperature history and IT. |
