The study, by researchers at the Agricultural University of Poznan looked at the effect of collagen preparations as carriers of iodine salts in pork meatballs and report that the carriers "The results of sensory evaluation and analyses of iodine and thiamine retention presented in this study indicate that collagen preparations (especially those with a high water binding capacity) may be used as alternative carriers of iodine salts in the production of processed meats," wrote authors Katazyna Waszkowiak and Krystyna Szymandera-Buszka.
Emerging evidence suggests that a widespread mild iodine deficiency exists in many countries.
The iodine content of food is a reflection of the environment, and as locally produced food is naturally low in iodine, it is difficult to meet dietary requirements through the diet.
Addition of iodine salts to foods is seen as a way of improving intake of this nutrient, but processing and in particular cooking is known to detrimentally effect iodine content.
Moreover, addition of such salts is also reported to increase the loss of the B vitamin thiamine from the product.
"Increasing the stability of potassium iodide during thermal processing and storage of enriched products would facilitate better control over the actual iodine content provided in this way to consumers," they added.
Waszkowiak and Szymandera-Buszka investigated the use of adding collagen fibre or collagen hydrolysate saturated with potassium iodide to fresh meat before cooking, and also the effects during cold- or freezer-storage Writing in the Journal of the Science of Food and Agriculture , the authors report that collagen fibre and collagen hydrolysate retaining iodine significantly more iodine after cooking than meatballs containing iodised table salt (88 and 84 versus 75 per cent, respectively).
After cold-storage there was no significant difference between the iodine content between collagen fibre and hydrolysate, but the fibre performed better at retaining iodine content after freeze storage.
Retention of thiamine was also improved by addition of the collagen preparations.
"The protective action of collagen towards potassium iodide needs to be linked with its functional properties," said the researchers.
"Since one of the essential factors having an adverse effect on the stability of potassium iodide is the moisture content, it may be assumed that the collagen preparation bound water, limiting in this way its contact with potassium iodide."
Commenting independently on the research Professor Hans Burgi of the International Council for Control of Iodine Deficiency Disorders (ICCIDD) in Switzerland said: "Since in iodine deficient areas, iodine is supplemented by salt as a carrier, improving its stability with collagen is of interest."
Source: Journal of the Science of Food and Agriculture Published on-line ahead of print, doi: 10.1002/jsfa.2844 "Effect of collagen preparations used as carriers of potassium iodide on retention of iodine and thiamine during cooking and storage of pork meatballs" Authors: K. Waszkowiak, K. Szymandera-Buszka