Stability of added iodine in different Indian cooking processes T. Longvah a,⇑ , G.S. Toteja b , G. Bulliyya c , R.S. Raghuvanshi d , Shashi Jain e , Vishnuvardhan Rao a , A. Upadhya f a National Institute of Nutrition, Jamai Osmania PO, Hyderabad 500007, India b Indian Council of Medical Research, Ansari Nagar, New Delhi 110 029, India c Regional Medical Research Centre, Bhubaneshwar 751 023, India d College of Home Science, G.B. Pant University, Pantnagar 263 145, India e Maharana Pratap University of Agriculture and Technology, Udaipur 313 001, India f Hislop College, Civil Lines, Nagpur 440 001, India article info Article history: Received 6 April 2011 Received in revised form 1 June 2011 Accepted 8 August 2011 Available online 16 August 2011 Keywords: Iodised salt Indian recipes Iodine retention abstract Universal salt iodisation programme is recognised as an economical, convenient and effective means of preventing iodine deficiency disorders (IDD). However, information on the retention of iodine during cooking is scant. Therefore this study was undertaken to investigate the retention of iodine from iodised salt when added to the most commonly used Indian recipes. The Mean ± SD retention of iodine in 140 of the most common Indian recipes was 60 ± 21%. The frequency distribution showed low retention (<20%) of iodine in 5.7% of the recipes, moderate retention (20–40%) in 15.7% while very high retention (>80%) was observed in 20%. Significant correlation (r = 0.194, P < 0.05) was observed between iodine retention and the time of iodised salt addition to the recipe. The retention of iodine was observed to be a minimum in shallow frying with oil (52 ± 23%) and a maximum in pressure cooking (82.2 ± 6.2%). The data gener- ated in this study would usefully augment the negligible information regarding iodine retention in recipes. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction Food is mankind’s major source of total iodine intake, with water and beverages also contributing small amounts. The iodine content of different foods depends on the iodine content of the soil where it is grown, which explains why the same food item may have a vastly different iodine content depending upon the locality where it is produced. In general, grain crops are poorer sources of iodine than vegetables. Green leafy vegetables contain higher lev- els of iodine than other vegetables but fish and seafood are the richest natural source in foodstuffs. Thus the proportion of each type of food consumed determines the dietary iodine exposure (EGVM, 2000; Fordyce, 2003; Haldimann, Alt, Blanc, & Blondeau, 2005; Longvah & Deosthale, 1998; WHO, 1996). Iodine occurs in foods mainly as inorganic iodide, which is read- ily, and almost completely, absorbed from the gastro intestinal tract. Iodine is required for the synthesis of thyroid hormones, thy- roxine (T4) and tri-iodothyronine (T3) which regulates a wide range of physiological processes. The thyroid must trap about 60 lg of iodine per day to ensure an adequate supply of thyroid hormones (Underwood, 1977). However in order to provide a margin of safety, the recommended daily intake of iodine is 90 lg for preschool children (0–59 months); 120 lg for school children (6–12 years); 150 lg for persons 12 years and above and 250 lg for pregnant and lactating women (WHO/UNICEF/ICCIDD, 2007). The inability to meet the requirement leads to a diverse ar- ray of iodine deficiency problems commonly termed as iodine defi- ciency disorders (IDD) (Hetzel, 1983). Currently, out of 130 countries for which national and sub- national level data is available on iodine deficiency, IDD still remains a public health problem in 47 countries despite concerted efforts to eradicate it (WHO/UNICEF/ICCIDD, 2007). Iodine defi- ciency is not only of nutritional and public health concern, but also a major impediment to human and economic development. Elimi- nation of Iodine deficiency is thus a global health priority and the only way to eliminate IDD is to make iodine available to the defi- cient population. From the public health point of view, universal salt iodisation programme is recognised as an economical, conve- nient and effective means of preventing IDD. The WHO/UNICEF/IC- CIDD (2001) has recommended fortification levels of iodine for salt at different levels, taking into consideration the environment and packaging conditions. In India, the mandatory minimum level of iodine in salt at the time of production is 30 and 15 ppm at the time of consumption. The actual availability of iodine from iodised salt at the con- sumer level can vary widely due to a number of factors including 0308-8146/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodchem.2011.08.024 ⇑ Corresponding author. Tel.: +91 40 27197216; fax: +91 40 27000339. E-mail address: tlongvah@gmail.com (T. Longvah). Food Chemistry 130 (2012) 953–959 Contents lists available at SciVerse ScienceDirect Food Chemistry journal homepage: www.elsevier.com/locate/foodchem