Wheat Bread: Potential Approach to Fortify its Lysine Content

Wheat bread is the main foodstuff and supply of dietary energy/protein in most developing countries. Wheat based diets are poor regarding essential amino acid content especially lysine as the first limiting amino acid. Since human body is unable to build lysine, it is necessary to be taken via food and/or supplements. Recommended daily intake of lysine is estimated to be around 30-64 mg/kg body weight. Inadequate intake of lysine results in a syndrome called ‘protein energy malnutrition’ which is suspected to be more prevalent in developing countries. Since lysine is provided by different sources (especially meat), there is no published data about the lack of lysine, however it is estimated to be prevalent in developing countries where the lysine-rich sources are generally expensive and low accessible there. The lysine fortification of wheat bread is conducted mainly to provide an accessible lysine-rich source. Biofortification, using lysine rich sources (either as flour or protein concentrates) and directly addition of lysine amino acid and its derivative have been investigated in different studies. The aim of this article is to review the potential strategies to improve the lysine content of wheat bread from both nutritional and technological points of view.