Spectrophotometric Determination of Total Vitamin C in Some Fruits and Vegetables at Koya Area – Kurdistan Region/ Iraq

Abstract

A simple UV- spectrophotometric method for the determination of the total vitamin C (ascorbic acid + dehydroascorbic acid) in various fruits and vegetables at Koya area in Kurdistan Region is described. The spectrophotometric method involves the oxidation of ascorbic acid to dehydroascorbic acid by bromine water in presence of acetic acid. After coupling with 2,4 -dinitrophenyl hydrazine at 37°C temperature for about three hours, the solution is treated with 85% H2SO4 to produce a red color complex. Then, the absorbance was spectrophotometrically measured at 280 nm. The content of vitamin C was 1.868 to 51.74 mg/10g in fruits and 0.841 to 17.416 mg/10g in vegetables.The standard deviation and the possible interfering factors are also discussed.