利用维生素C对紫外产生吸收和对碱不稳定的特性,用紫外分光光度法测定5种常见果蔬中维生素C的含量。最大吸收波长为243.4nm,标准曲线方程为A=0.0528c-0.0568,相关系数为R2=0.9996。5种果蔬中维生素C含量[mg.(100g)-1]分别为:青椒117.1、橙子69.3、黄瓜20.5、苹果14.9、西红柿18.4。该方法简单、快速,结果令人满意。

The vitamin C contents in five familiar fruits and vegetables were determined by UV spectrophotometry on the basis of the vitamin C characters of UV absorbing and alkali instability.The maximum absorbing wavelength of vitamin C determination by UV spectrophotometry was 243.4 nm,the standard curve equation was A=0.0528c-0.0568,the correlation coefficient R2=0.9996.The vitamin C content in green pepper,citrus junos,cucumber,apple,tomato was 117.1 mg·(100 g)-1,69.3 mg·(100 g)-1,20.5 mg·(100 g)-1,14.9 mg·(100 g)-1 and 18.4 mg·(100 g)-1,respectively.The determination of vitamin C content by UV spectrophotometric method was simple and fast with satisfactory result.