African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5232

Full Length Research Paper

The stability of micronutrients in fortified food stuffs after processing and storage: Iodine in salt and iron in wheat flour

Abebe Ayelign1*, Kelbessa Urga2 and Negussie Retta1    
  1Faculty of Science, Food Science and Nutrition program, Addis Ababa University, Addis Ababa, Ethiopia. 2Ethiopian Health and Nutrition Research Institute, Addis Ababa, Ethiopia.  
Email: [email protected]

  •  Accepted: 21 October 2011
  •  Published: 30 May 2012


Salt was fortified by potassium iodate in the level 66 mg/kg of salt with wet method of fortification. Then the iodized salt was stored using three packaging materials; low density polyethylene (LDPE), high density polyethylene (HDPE) and woven high density polyethylene (WHDPE) at two conditions: room temperature (20-25°C) and medium RH (50-60%) for about 6 months and accelerated temperature (40°C) and high Relative Humidity (RH) (70-100%) for about 18 days. Generally, the amount of iodine decreased with time (p < 0.05) but accelerated storage resulted in rapid loss of iodine. Among the three packaging materials used, HDPE retained iodine from iodized salt better than the other two packaging materials. In addition, a significant amount of iodine was lost from the iodized salt after processing the iodized salt at different temperatures. Wheat flour was fortified by ferrous sulfate in the level 40 mg/kg of wheat flour for room temperature (for 45 days) storage and 30 mg/kg of wheat flour for accelerated temperature (40°C) and high RH (70-100%) (for 4.5 days) storage. For both storage conditions iron was found to be stable (p > 0.05). When the amount of iron was evaluated after processing (baking bread), the result was found to be non-significantly different. In addition, the sensory quality scores of the 30 and 40 ppm iron fortified bread were above moderately liked scale and were not different from the bread made from the control.


Key words: Fortification, salt, wheat flour, micronutrients, iron, iodine, storage, relative humidity, temperature, packaging materials, processing, sensory evaluation.