Biofortification of maize and sweetpotatoes with provitamin A carotenoids and implication on eradicating vitamin A deficiency in developing countries

Abstract

Vitamin A deficiency (VAD) continues threatening lives of many children and adults in many developing countries. While many strategies such as vitamin A supplementation and food fortification have been put in place, the decrease in VAD still remains slow while in some countries improvement has only been modest. This is attributed to poor coverage and compliance by targeted population. Biofortification overcomes these shortfalls by targeting crops already consumed by a majority of population and therefore has a wider reach. Unfortunately biofortification has its problems that need to be addressed in order to make it an effective tool in reducing VAD. Though the International Maize and Wheat Improvement Center (CIMMYT)/International Institute of Tropical Agriculture (IITA) and International Potato Center (CIP) have recently released biofortified maize and orange-fleshed sweetpotatoes (OFSP) varieties, respectively, that compare very well with traditional varieties in terms of yield and environmental adaptability, the yield of some available biofortified varieties are comparatively lower compared to traditional white varieties. Moreover, provitamin A carotenoids are highly oxidative resulting into significant losses during both storage and processing thereby lowering nutritional values of final products. Proper storage of these crops may slow down carotenoid loss. Though different processing methods increase carotenoid losses, they consequently increase their bioaccessibility and bioavailability. With genetic improvement in the past decade that has resulted into better varieties coupled with more awareness campaigns and nutrition education about the nutritional superiority of biofortified crops, adoption and home utilization of these crops will continue to increase. Developing different products from these biofortified crops can go a long way in increasing acceptability and utilization and consequently increase dietary intake of provitamin A carotenoids. This review therefore presents some of the progress made on biofortified maize and sweetpotatoes and highlights challenges facing biofortification and how they are being addressed.

Keywords

• Biofortification
• Provitamin a carotenoids
• Vitamin a deficiency
• Sweetpotatoes
• Orange maize
• Carotenoid degradation