The Titrimetric and Spectrophotometric Determination of Ascorbic acid levels in Selected Nigerian Fruits

Abstract

In this study, the ascorbic acid levels in mango, pawpaw, pear, banana and plantain were determined by titrimetric and spectrophotometric methods using oxalic acid and orthophosphoric acid as extracting solvents. The yield of ascorbic acid by titrimetric method ranged from 0.20 ± 0.02 mg/100g to 13.20 ± 0.05 mg/100g while spectrophotometric method ranged from 7.76 ± 4.7 mg/100g to 87.1 ± 6.3 mg/100g. Regardless of the extracting solvents and the estimation methods, the results revealed that ascorbic acid content was very high in pawpaw and mango while it was very low in plantain, banana and pear. Comparison of the two estimation methods indicated that spectrophotometric method detected more ascorbic acid than titrimetric method in all the selected samples. While the results from both methods are generally comparable in all the samples, the spectrophotometric method is a preferred method because higher contents of ascorbic acid were obtained relative to the titrimetric method.