Stability of the salt iodization agent potassium iodate: a differential thermal analysis / 中国地方病学杂志

ABSTRACT

Objective To investigate the thermal stability of solid potassium iodate and potassium iodate as additive in the sodium chloride,vitamin E,vitamin C and yellow prussiate.Methods HCR-2 type Differential Thermal Analyzer was used to carried out the differential thermal analysis of the potassium iodate and the potassium iodate in the sodium chloride,vitamin E,vitamin C and the yellow prussiate,and differential thermal curves were obtained and analyzed.Results The decomposition temperature of solid potassium iodate was 525℃ ; when mixed with sodium chloride,potassium iodate was stable below 300 ℃ ; vitamin C was unstable at 170-200 ℃ and underwent chemical changes; iodate and vitamin C underwent oxidation-reduction reaction at 145 to 160 ℃;potassium iodate with vitamin E at 300 ℃ was stable; yellow prussiate at 300 ℃ was stable; iodized salt was stable at cooking temperature below 300 ℃.Conclusions The potassium iodate has good stability below 525 ℃,however,potassium iodate iodized salt in the cooking process is easy to react with vitamin C in vegetables causing iodine losses,so iodized salt should be added just before the dish is done.