碘量法测水果蔬菜中维生素C的含量  

Determination of Ascorbic Acid in Vegetables and Fruits by Iodimetry

作　　者：库尔班江[1] 赛丽曼[2] 

机构地区：[1]伊犁师范学院化学与生物科学学院 [2]伊犁州技工学校,新疆伊宁835000

出　　处：《伊犁师范学院学报（自然科学版）》2007年第3期28-32,共5页Journal of Yili Normal University：Natural Science Edition

摘　　要：采用碘量法测定了当地产水果、蔬菜中维生素C的含量.因抗坏血酸有极强的还原性,而I2有强的氧化性,二者可定量地发生反应,因此先用纯品抗坏血酸配成的标准溶液标定配制的I2溶液,再用已标定的I2溶液滴定样品的提取液,用1%的淀粉溶液为指示剂,当滴至褪色且在30s不变色,则为滴定终点,计算出维生素C的含量.结果表明,此法较为成熟,条件易控制,操作快速方便、仪器简单,平均回收率为105.02%,其回归方程为Y=1.9144X+0.1962,R=0.9985.为一般基层机构对水果、蔬菜的质量控制提供了科学依据和可靠的方法.This experiment adopts iodimetry to ascertain the concentration of Vc in common fruits and vegetables. First,using the standard solution which is made up with pure Ascorbic Acid to standardize I2 solution that have been made up,then using the I2 solution which is standard to titration the extracted solution of the sample and the indicator should be 1% starch solution. That is not the end of titration until the titration solution change into slight blue and it won’t fade in 30 minutes. Finally,we can calculate the concentration of Vc in fruits and vegetables. This experiment shows that iodimetry is easy to operate. In this experiment the average rate of recovery is R=105.02% and the standard linear equation is Y=1.9144X+0.1962,R=0.9985.

关 键 词：碘量法 水果 蔬菜 抗坏血酸 维生素C 含量 测定 

分 类 号：TS255.7[轻工技术与工程—农产品加工及贮藏工程]