摘要
目的:测定部分蔬菜水果中维生素C含量,测定碱、重金属盐和高温处理对维生素C的破坏作用。方法:采用2,6-二氯酚靛酚氧化还原滴定法测定部分蔬菜水果中维生素C的含量;采用不同浓度NaOH,不同浓度CuSO_4,不同温度处理,测定这些因素对维生素C的破坏作用。结果:鲜枣、猕猴桃、青椒等含量较高,每100g样品含维生素C分别达287mg、200mg和116mg;碱(NaOH)对维生素C有破坏作用,随着碱性增强破坏程度越来越大;重金属(Cu^(2+))对维生素C有破坏作用,随着CuSO_4浓度的增加,破坏程度逐渐加大;高温对维生素C有破坏作用,60℃处理已有破坏,随着温度的升高破坏程度越来越大。结论:水果蔬菜中维生素C含量差异较大,且维生素C极不稳定,易受到碱、重金属及高温等因素破坏。
Objectives to determine the vitamin C content in some fruits and vegetables, to determine vitamin C's stability under the treatment of three factors including base, heavy metal salt and high temperature. Methods using the 2,6-dichlorophe—nolindophenol oxidation-reduction titration method to determine the vitamin C content in some fruits and vegetables; using a series of NaOH and CuSO_4 concentrations and temperatures to treat vitamin C to determine stability of vitamin C. Results fresh Chinese date, Chinese goosebeery and green pepper contain vitamin C much higher than other fruits or vegetables, the figures are 287 mg, 200 mg and 116 mg per 100 g sample respectively; base(NaOH) has the destructive effect on vitamin C and the destructive extent is direct proportional to the concentration of base; heavy metal salt(CuSO_4) has destructive effect on vitamin C and the destructive extent is direct proportional to the concentration of the salt; high temperature has destructive effect on vitamin C, treat with 60℃ begins to destroy vitamin C, the extent of destruction becomes higher with the increase of temperature. Conclusions the differences of vitamin C contents in fruits and vegetables are large, and vitamin C is instable, it can be destroyed by the factors such as base, heavy metal salt and high temperature.
出处
《科教导刊》
2017年第12Z期60-61,共2页
The Guide Of Science & Education
