Investigating carotenoid loss after drying and storage of

1.1 BACKGROUND
1.1.1 Introduction
CHAPTER 1.
LITERATURE REVIEW
1
1. Literature review
Vitamin A deficiency is a major public health issue in developing countries; with
children and pregnant/lactating women the most vulnerable (FAO/WHO 2002). Sub-
Saharan Africa is one of the most affected areas with 33 million pre-school children who
are deficient, which accounts for a third of the world cases (West 2002).
There are different strategies to tackle vitamin A deficiency. Traditional interventions
consist of administration of vitamin A capsules. Although a single dose can be given
every six months or every year, these medical interventions are costly (Nestel et al.
2006). Food fortification is another approach used to reduce vitamin A deficiency that
works by adding vitamin A to food commodities (e.g. sugar). An alternative approach is
biofortification, which consists of breeding staple crops to increase their content of
vitamins and/or minerals. Compared to the two other strategies, biofortification is
considered a more sustainable approach because it has the potential to provide vitamins
or minerals throughout the year with a one-off intervention and in the longer term at
lower cost (Kósambo et al. 1998). For the same level of impact on public health, the cost
of biofortification is estimated to be half that of vitamin A supplementation (Nestel et al.
2006). Moreover, rural and low-income communities, which have been shown to be
more at risk, can be reached by this approach and it also creates opportunities for income
generation from production and marketing of these crops.
Sweet potato is a very important crop that is widely consumed in sub-Saharan Africa and
Uganda one of the major producers (Woolfe 1992). In sub-Saharan Africa the majority
of sweet potato that is consumed is white-fleshed and has low levels of provitamin A (β-
carotene) (Ameny and Wilson 1997). There are efforts through the Vitamin A
Partnership for Africa (VITAA) Initiative and also through a Bill and Melinda Gates