Color stability and biochemical characteristics of bovine muscles when enhanced with L- or D-potassium lactate in high-oxygen modified atmospheres.

Two different bovine muscles -M.longissimus lumborum (LD) and M. psoas major (PM) - were injection-enhanced (n=10, respectively) with solutions containing phosphate and potassium L- or D-lactate, cut into steaks, packaged with a high-oxygen (80% O(2)) modified atmosphere packaging, stored 9d at 2°C and then displayed for 5d at 1°C. Instrumental color, total reducing activity (TRA), lactate dehydrogenase (LDH) activity, and NADH were measured. Enhancement with L-lactate resulted in less color deterioration, and higher a(∗) and chroma values (P<0.05) than non-enhanced control of the bovine muscles. L-lactate enhancement significantly increased NADH concentration and TRA of LD and PM than the non-enhanced control through increased LDH-B flux at 14d. This study presents supportive evidence that the lactate-LDH system remains active for muscles with different metabolic activities and may be a possible mechanism of the lactate-color stabilization effect. Further, L-lactate enhancement can be utilized for improving muscles with lower color stability in high-oxygen modified atmosphere.