Study on folate stability during thermal processing

Abstract

Stability of folate at different pH (3 to 9) toward thermal (65 to 140oC) treatments was studied on a kinetic basis. Residual folate concentration after thermal treatment was measured using reverse phase liquid chromatography. A model to describe the temperature effect on folate degradation rate constant is presented with the degradation of folates followed first-order reaction kinetics. The estimated Arrhenius activation energy (Ea) values of folate thermal degradation were determined.At all pH values studied, it was found that (i) folic acid and 5-formyltetrahydrofolic acid were more thermo stable than tetrahydrofolic acid and 5-methyltetrahydrofolic acid and (ii) all folates studied had the highest stability at neutral pH (pH 7.0) or alkaline pH (pH 9.2).

Keywords

• Folate
• thermal
• kinetic
• stability
• pH