Research for Selecting The Optimized Vitamin C Analysis Method

摘要

2,4-Dinitrophenylhydrazine (DNP), indophenol, and HPLC methods, which are generally used to analyze vitamin C, were evaluated by comparing changes in vitamin C contents in various samples kept at 10 and 20°C. Amount of total ascorbic acid (TAA) in yoghurt A kept at 10°C, as measured by DNP method, decreased from 26.7 mg/ 100 mL for early period to 22.8 mg/100 mL for final period of storage, whereas, on 3rd and 10th storage days, increased contrary to general results. Using indophenol, TAA measuredat 28.6 and 9.5 mg/100 mL, and 30.5 and 14.6 mg/100 mL using HPLC for early and final periods, respectively. With indophenol and HPLC, TAA amount showed steady tendency to decrease. In conclusion, HPLC is the most suitable method to analyze vitamin C content, and indophenol method can be also used during early storage stage.