Storage conditions and packaging greatly affects the stability of fortified wheat flour : influence on vitamin A, iron, zinc, and oxidation

Micronutrient deficiencies result in irreversible physical and cognitive consequences. Fortification of flour is widely applied to address micronutrient deficiencies, but vitamin losses can occur during the storage of fortified products. This work aimed at assessing the combined influence of different factors on vitamin A retention and the oxidative status of wheat flours: storage duration (up to 6 months), temperature during storage, relative humidity within storage facilities, type of packaging (oxygen-permeable or not), and premix composition (with or without ferrous sulphate). Vitamin A degradation was high and occurred rapidly: more than 45% was lost within 3 months in the mildest conditions, whereas over 85% was lost within 3 months in the most severe conditions. Vitamin A retention was related to the extent of oxidation reactions that occurred in flours during storage, and the factors that mostly affected vitamin A retention were the storage duration, the type of packaging and the temperature