碘与铁强化盐中碘的稳定性。

Ranganathan Srinivasaiyengar, Karmarkar Madhu G, Krupadanam Muddepaka, Brahmam Ginnela N V, Rao Mendhu Vishnuvardhana, Vijayaraghavan Kamasamudram, Sivakumar Bhattriprolu

Isotope Division, National Institute of Nutrition, Indian Council of Medical Research, Hyderabad 500 007, India.

Food Nutr Bull. 2007 Mar;28(1):109-15. doi: 10.1177/156482650702800112.

BACKGROUND

Determining the stability of iodine in fortified salt can be difficult under certain conditions. Current methods are sometimes unreliable in the presence of iron.

OBJECTIVE

To test the new method to more accurately estimate iodine content in double-fortified salt (DFS) fortified with iodine and iron by using orthophosphoric acid instead of sulfuric acid in the titration procedure.

METHODS

A double-blind, placebo-controlled study was carried out on DFS and iodized salt produced by the dry-mixing method. DFS and iodized salt were packed and sealed in color-coded, 0.5-kg, low-density polyethylene pouches, and 25 of these pouches were further packed and sealed in color-coded, double-lined, high-density polyethylene bags and transported by road in closed, light-protected containers to the International Council for the Control of Iodine Deficiency Disorders (ICCIDD), Delhi; the National Institute of Nutrition (NIN), Hyderabad; and the Orissa Unit of the National Nutrition Monitoring Bureau (NNMB), Bhubaneswar. The iodine content of DFS and iodized salt stored under normal room conditions in these places was measured by the modified method every month on the same prescribed dates during the first 6 months and also after 15 months. The iodine content of DFS and iodized salt stored under simulated household conditions was also measured in the first 3 months.

RESULTS

After the color code was broken at the end of the study, it was found that the DFS and iodized salt stored at Bhubaneswar, Delhi, and Hyderabad retained more or less the same initial iodine content (30-40 ppm) during the first 6 months, and the stability was not affected after 15 months. The proportion of salt samples having more than 30 ppm iodine was 100% in DFS and iodized salt throughout the study period. Daily opening and closing of salt pouches under simulated household conditions did not result in any iodine loss.

CONCLUSIONS

The DFS and iodized salt prepared by the dry-mixing method and stored at normal room conditions had excellent iodine stability for more than 1 year.

背景

在某些条件下，确定强化盐中碘的稳定性可能具有挑战性。在有铁存在的情况下，目前的方法有时并不可靠。

目的

通过在滴定过程中使用正磷酸代替硫酸，测试一种新方法，以更准确地估计同时添加碘和铁的双重强化盐（DFS）中的碘含量。

方法

对通过干混法生产的DFS和加碘盐进行了一项双盲、安慰剂对照研究。DFS和加碘盐被包装并密封在带有颜色编码的0.5千克低密度聚乙烯袋中，其中25个这样的袋子进一步被包装并密封在带有颜色编码的双层高密度聚乙烯袋中，并通过公路运输，装在封闭的、防光的容器中，运往位于德里的国际碘缺乏病控制理事会（ICCIDD）、位于海得拉巴的国家营养研究所（NIN）以及位于布巴内斯瓦尔的国家营养监测局（NNMB）奥里萨邦分部。在最初6个月的相同规定日期每月以及15个月后，使用改良方法测量这些地方在正常室温条件下储存的DFS和加碘盐的碘含量。在最初3个月还测量了在模拟家庭条件下储存的DFS和加碘盐的碘含量。

结果

在研究结束时打破颜色编码后发现，在布巴内斯瓦尔、德里和海得拉巴储存的DFS和加碘盐在最初6个月内或多或少保留了相同的初始碘含量（30 - 40 ppm），15个月后稳定性未受影响。在整个研究期间，DFS和加碘盐中碘含量超过30 ppm的盐样本比例均为100%。在模拟家庭条件下每天打开和关闭盐袋并未导致任何碘损失。