title: Temperature- and pH-dependent effect of lactate on in vitro redox stability of red meat myoglobins.
abstract: Our objective was to evaluate the influence of lactate on in vitro redox stability and thermostability of beef, horse, pork, and sheep myoglobins. Lactate (200 mM) had no effect (P>0.05) on redox stability at physiological (pH7.4, 37°C) and meat (pH 5.6, 4°C) conditions. However, lactate increased (P<0.05) metmyoglobin formation at a condition simulating stressed live skeletal muscle (pH 6.5, 37°C). The redox stability of myoglobins at stressed live skeletal muscle and meat conditions was species-specific (P<0.05). Myoglobin thermostability at 71°C was lower (P<0.05) in the presence of lactate compared with controls and was influenced (P<0.05) by species. The results of the present study indicate that the effects of lactate on myoglobin are temperature and pH dependent. The observed lack of influence of lactate on myoglobin redox stability at meat condition suggests that the color stability of lactate-enhanced fresh meat is not due to direct interactions between the ingredient and the heme protein.
authors: Department of Animal and Food Sciences, University of Kentucky, Lexington, KY 40546, USA.
authors: M N
authors: MN
authors: Nair
authors: S P
authors: SP
authors: Suman
authors: S
authors: S
authors: Li
authors: R
authors: R
authors: Ramanathan
authors: R A
authors: RA
authors: Mancini
mesh_terms: D000818:Animals; D002417:Cattle; D003116:Color; D006736:Horses; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000494:pharmacology*; D008460:Meat / Q000032:analysis*; D018482:Muscle, Skeletal / Q000737:chemistry*; D009211:Myoglobin / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects*; D012756:Sheep; D013552:Swine; D013696:Temperature
chemical_list: D009211:Myoglobin; D019344:Lactic Acid
keywords: Lactate; Meat color; Myoglobin; Redox stability; Thermostability