DEGRADATION KINETICS OF ASCORBIC ACID AND Β-CAROTENE IN MANGO SLICES USING DIFFERENT DRYING METHODS

Abstract

Ascorbic acid and β-carotene are one of the most important vitamins that is essential in human system. Freshly mango was procured from a local farmer in Ogbomoso, Oyo State Nigeria. Mango was sorted, washed to remove extraneous material, peeled, and then cut into slice thicknesses of 3, 6, and 9 mm. The sliced mango samples were dried using three drying methods: oven (40, 45 and 50 °C), solar and sun drying methods. Degradation kinetic of ascorbic and β-carotene was determined and it follow first order kinetics. Half-life and D-value were also determined. For ascorbic acid, the mean value of rate constant at drying temperature of 40 °C was 0.0265 min-1; for 45 °C was 0.0279 min-1; for 50 °C was 0.0344 min-1 while that of solar and sun were 0.0541 min-1 and 0.0546 min-1, respectively. For β-carotene, the range of values of rate constant for the three drying methods considered were 0.0259 - 0.05342 min-1; 0.0265 - 0.05342 min-1and 0.0270 - 0.0561 min-1 for slice thicknesses of 3, 6 and 9 mm, respectively. Half- life and β-carotene value decrease with increase in drying temperature for all the drying methods considered. In conclusion, due to reduction in ascorbic acid and β-carotene, it was inferred that heat has effect on the two vitamins considered.