Stability of Vitamin A in Nigerian Retailed Biscuits

Abstract

Vitamin A deficiency is a major public health problem affecting poor populations in developing countries. Biscuits baked with Nigerian vitamin A fortified flour (30 IU/g) have been consumed by pre-school children. This study aims at determining vitamin A content and stability in retailed biscuits at point of consumption. Pre-tested, semi-structured, interviewer-administered questionnaire was used to collect biscuit consumption pattern of pre-school children (n=1600). Out of 18 brands of biscuits reported, eight cartons of 8 commonly consumed brands were purchased from major markets in Lagos. Vitamin A (retinol) stability was determined by storing biscuit samples for 30 days. Pre- and post-storage retinol analyses were carried out using high performance liquid chromatography. Vitamin A stability was calculated as percentage of initial vitamin A biscuit values. Crunchiness and packaging of biscuit samples were also assessed. Data were analysed using descriptive and T-test at p<0.05. At pre-storage level, 62.5 % and 37.5 % samples had vitamin A and zero contents respectively. At post-storage, 25% had vitamin A content while 75% had zero content. Pre- and post-storage vitamin A content of samples was 5.2±4.9 IU/g and 1.9±1.8 IU/g. Mean vitamin A stability and loss in retailed biscuits at 2 months was 16.8% and 83.2% respectively. A significant difference was found in vitamin A content and stability of biscuits at pre- and post-storage levels. Biscuits lost crunchiness at post-storage level. Vitamin A content of retailed biscuit samples was below 30 IU/g resulting in very low stability. Use of fortified quality raw materials and compliance are essential.