食物烹调方法对含碘食盐中碘含量的影响

Effects of Cooking Methods on Iodine Content in Iodized Salt

本实验研究了含碘食盐中碘在食物烹调中的保留率，以及食物对含碘食盐中碘的保留率的影响，选择市售的蔬菜，按民间常用的烹调方法烹调，并规定了各种烹调方法的详细步骤。采用碳酸钾固定碘，在５５０℃下硫酸锌助灰化，砷铈接触比色法测定碘含量。不同烹调方法对含碘食盐中碘的保留率影响不同。炖和蒸的烹调方式使碘的保留率一般大于炒的。烹调过程中不同蔬菜对碘盐中碘的保留率有一定的影响，茄果类、叶菜类、根茎类、豆类在炒的过程中碘保留率依次为８４．２％，５６．９％，４４．５％，３６．６％。茄果类、根茎类、豆类、畜肉类在炖的过程中碘保留率依次为６６．１％，５３．４％，４７．０％，４３．２％。

Effects of cooking methods and variety of foods on the retention of iodine content in food with iodized salt were studied. Vegetables from market and usual cooking methods were selected, including procedures of various cooking methods. The samples were fixed by potassium carbonate, ashed with zinc sulfate at 550℃,then determined by colorimetric method with Ce As I catalytical reaction. The different cooking methods had different effects on the retention of iodine, in general, the retention of iodine by stewing of steaming was higher than by stir frying. The effect of various vegetables on the retention of iodine was also different. The retention of iodine after stir frying was 84 2%,56 9%,44 5%,36 6%for fruit bearing vegetables, leafy vegetables, roots and beans. The retention of iodine after stewing was 66 1%,53 4%,47 0%, and 43 2% for fruit bearing vegetables, roots, beans and meat. The stability of organic iodine in food is higher than that of inorganic iodine.