Temperature and pressure stability of l-ascorbic acid and/or [6s] 5-methyltetrahydrofolic acid: A kinetic study

摘要

Processing (i.e. pressure and temperature) stability of l-ascorbic acid (l-AA) and/or [6S]-5-methy-ltetrahydrofolate ([6S]-5-CH3-H4folate) was studied on a kinetic basis using different vitamin and initial oxygen concentrations. Stability of both folate and l-AA was enhanced by increasing the vitamin concentration or by decreasing the oxygen concentration. Based on this study, it was concluded that (i) l-AA increased the folate stability during processing; (ii) the molar ratio between l-AA or folate and the initial oxygen content was an important parameter to determine the proportion of aerobic degradation; and (iii) the minimum concentration of l-AA needed to prevent the oxidation of folate was at least 2 times as high as the molar concentration of the initial oxygen content when l-AA exists as a single antioxidant in the system.