Sodium lactate influences myoglobin redox stability in vitro
Injection-enhancement of beef with lactate improves color stability;
however, the mechanism is unclear. Thus, our ives were to assess
the effects of sodium lactate on equine myoglobin redox stability in
vitro. Oxymyoglobin at pH 5.6 (50 mM sodium citrate) and pH 7.4 (50 mM
sodium phosphate) was incubated at 4 °C with lactate (0, 5, 10, 100, or
200 mM) and myoglobin redox form was determined using absorbance
spectra. Metmyoglobin formation at pH 5.6 and 7.4 was significantly (P < 0.05)
decreased by lactate at concentrations of 100 and 200 mM. In general,
increasing lactate concentration from 100 to 200 mM increased (P < 0.05)
oxymyoglobin redox stability. This effect of lactate on myoglobin redox
stability could be partially responsible for the improved color
stability associated with lactate injection-enhanced beef products.
Further work should determine the effect of lactate on beef myoglobin.