Indigenous food processing methods that improve zinc absorption and bioavailability of plant diets consumed by the Kenyan population

Abstract

Zinc deficiency is a public health problem associated with pregnancy complications
and birth outcomes, impaired immune function, and increased duration and severity of
diarrhea in children. Zinc is an essential trace mineral that is a component of over 200
enzymes and is known to be necessary for normal collagen synthesis, mineralization
of bones, and is also involved in vital processes such as mitosis, synthesis of DNA
and protein, and gene expression and activation. In many low-income countries diets
are composed primarily of cereals and legumes which contain phytate that inhibit zinc
absorption. Most Kenyan diets are composed of cereals and legumes that have high
content of zinc inhibitors, whose levels may be reduced through appropriate food
processing technologies at the household level. Indigenous food processing methods
like soaking, germination, drying, fermentation, boiling, and roasting, and diet
combinations usually reduce the levels of zinc antagonists in the plant diets, thus
increasing zinc absorption and bio-availability. These methods are used in
combination to both enhance organoleptic properties of food, increasing acceptability
and also promoting complementation of nutrients. There are food combination
patterns that enhance nutrient bioavailability and complementation that was known to
most traditional households and are quickly being forgotten due to changing lifestyles,
food preparation methods and food tastes. This is worsened by lack of proper
knowledge transfer from the older generation. However, the transfer of indigenous
knowledge in food processing, preparation and diet combinations need to be profiled
to identify processes that promote nutrient content and bioavailability for improved
health and nutrient situation of rural populations whose diets are basically plant based.
There is need to identify suitable sources of absorbable zinc and possible suitable
dietary combinations that can contribute towards the reduction of zinc deficiency.
This paper discusses the indigenous food processing methods that enhance zinc
absorption and bioavailability of zinc in local dietary combinations that could reduce
zinc deficiency.

Keywords: Zinc, soaking, germination, drying, fermentation.

AJFAND Vol. 9 (1) 2009: pp. 524-535