Investigating carotenoid loss after drying and storage of

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1. Literature review
Vitamin A deficiency affects over 127 million pre-school children (West 2002) and is
reported to affect 38% of the children under five in Uganda (Ugandan Bureau of
Statistics 2001) and 71% of the children in Mozambique (Aguayo and Baker 2005). This
corresponds to an estimated 2.3 million children under five in each of Uganda and
Mozambique.
In order to tackle vitamin A deficiency, daily nutritional needs in vitamin A for different
class-ages were evaluated by FAO/WHO. The mean requirement intake is the minimum
intake to prevent xerophtalmia in the absence of clinical or sub-clinical infection.
Recommended safe intake is the average intake of vitamin A to permit adequate growth
and other vitamin A dependent functions and maintain an acceptable total body reserve
of the vitamin (FAO/WHO 2002). Recommended safe intake is also called
Recommended Dietary Allowance (RDA). These requirements in microgram retinol
equivalents per day (!g RE/day) are summarised in Table 1-1.
Table 1-1: Estimated mean requirement and safe level of intake for vitamin A.
FAO/WHO (2002).
Some earlier studies estimated that 6 µg of "-carotene from plant sources were providing
one retinol equivalent (RE). More recent studies have however suggested that the
appropriate conversion factor varies by plant species and might be much lower (Sommer
1998). Consequently conversions factors published by National Academy of
Sciences/Institute of Medicine (2001) stated that 12 µg of "-carotene (or 24 µg of other
carotenoids such as #-carotene, 5,6-epoxy-β-carotene and β-cryptoxanthin) found in