Contribution of genetic influences to animal-to-animal variation in myoglobin content and beef lean color stability1

Abstract

Longissimus thoracis steaks from steers (n = 464) with 0 to 50% inheritance of Angus, Charolais, Gelbvieh, Hereford, Limousin, Red Angus, and Simmental were evaluated during 6 d of display to assess genetic contributions to color stability. Color space values [CIE L* (lightness), a* (redness), b* (yellowness)], chroma, color change (DeltaE), and surface metmyoglobin (K/S 572/525) were determined on d 0 and 6 of display. Myoglobin concentration was highly heritable (0.85), but ultimate pH was weakly heritable (0.06). Day 0 L* values were moderately heritable (0.24). Variation in metmyoglobin, L*, and DeltaE on d 6 was moderately explained by genetic factors (41, 40, and 29%, respectively). Change during display was moderately heritable for a* (0.31), b* (0.23), chroma (0.35), and surface metmyoglobin (0.29). At the start of display, Angus steaks had greater (P < 0.05) L* values than those from all breeds except Charolais. On d 6, Angus steaks had greater (P < 0.05) L* (50.0) values than Gelbvieh, Hereford, and Simmental steaks (46.1, 44.0, and 44.5, respectively). Day 0 values for a*, b*, chroma, and DeltaE were not affected by breed (P > 0.05). On d 6, a* values were greater (P < 0.05) for Charolais and Limousin steaks (31.1 and 30.5) than Angus, Hereford, and Red Angus steaks (27.4, 27.7, and 26.3, respectively). Thus, a* changed less (P < 0.05) in Charolais and Limousin steaks (1.8 and 2.6, respectively) vs. steaks from other breeds. Day 6 b* values were greater (P < 0.05) in Charolais (24.5) and Limousin steaks (24.0) vs. Gelbvieh (22.2), Hereford (21.9), and Red Angus steaks (21.4). Thus, b* values changed less (P< 0.05) in Charolais and Limousin steaks (1.5 and 1.7, respectively) than in Angus, Gelbvieh, Hereford, and Red Angus steaks (4.3, 3.8, 4.4, and 5.1, respectively). After 6 d of display, Charolais and Limousin steaks had greater chroma (P < 0.05; 39.5 and 38.8, respectively) compared with Angus, Hereford, and Red Angus steaks (35.4, 35.3, and 33.9, respectively). Less (P < 0.05) change in chroma occurred for Charolais and Limousin (2.1 and 2.8, respectively) than in Angus, Gelbvieh, Hereford, and Red Angus steaks (7.1, 6.6, 7.4, and 9.0, respectively). Myoglobin concentration was less for Charolais and Limousin (P < 0.05; 2.77 and 2.72, respectively) compared with Gelbvieh, Red Angus, and Simmental steaks (3.62, 3.43, and 3.71, respectively). Breeds did not differ in pH (P > 0.05). These data suggest Charolais- and Limousin-carcasses produced steaks with greater lean color stability than Angus, Hereford, and Red Angus carcasses. Furthermore, these findings suggest that genetics contribute substantially to animal-to-animal variation in lean color, particularly in maintaining color.

Sire breed effect on beef longissimus mineral concentrations and their relationships with carcass and palatability traits

“…While this study does not identify a breed effect in regard to total muscle iron, non-heme iron, nor heme iron, King et al (2010) found that myoglobin concentration in LT steak was highly heritable (h 2 = 0.85) and myoglobin did vary among breeds with myoglobin concentration higher in Gelbvieh, Red Angus, and Simmental than in Charolais and Limousin cattle.…”

Exogenous and Endogenous Factors Influencing Color of Fresh Meat from Ungulates

“…King et al (2010) reported that there was substantial animal-to-animal variation (within a species and breed) in beef color and that animal-to-animal differences played a larger role in the capacity of the muscle to maintain its color, rather than in its initial color. Furthermore, these authors highlighted the existence of opportunities to improve color stability through genetic selection.…”

Relative contributions of animal and muscle effects to variation in beef lean color stability1,2

“…Thus, color stability research has focused on differences due to ante-or postmortem management (Ledward, 1985;Lawrence et al, 2004;Mancini et al, 2008) and across muscles (Talmant and Monin, 1986;McKenna et al, 2005). However, previous work from our laboratory has substantiated the importance of animal variation and indicated that genetic influences contribute to animal variation in lean color stability (King et al, 2010).…”

“…However, given the evidence that these factors also vary substantially within the LM and contribute to variation in color stability in the LM (King et al, 2010(King et al, , 2011, it appears that significant opportunity exists to use genetic selection and management to reduce animal variation in color stability. The present experiment was conducted to characterize the relative contribution of animal and muscle effects to beef lean color stability.…”