For
restoration of vitamins and mineral cost during milling, the enrichment of rice is
important for better nutrition. There are two major approaches. Powder
enrichment and coated kernel enrichment. For pre-blended powder enrichment, mixes
includes, thiamins riboflavins, niacin, niacinamind, ferric orthophophate
(white iron) ferrous sulphate (yellow iron) or reduced iron which is relatively water
insoluble and white-in colour (HOWpaur 1992). This is an easy and less expensive approaches for
enrichment of rice. But the disadvantages of the powder enrichment are that
the nutrient are easily washed off by rinsing, less stability of
vitamins, and minerals and their reaction with the food component. An
alternative approach is the coated kernel enrichment this method integrates
the powder blended enrichment with insoluble food grads coating.
This
coating is broken down and the enriched vitamins and minerals. After enrichment, the
nuti%nt levels are the same as those of brown rice. The miltintrient
enriched rice is blended with rice at ratio of 1:200 only 10 percent of any nutrient is lost through
ordinary washing before
cooking and another 10 percent on cooking (Juliano 1993). The pioneering
enrichment field studies in Bothan province, the phillppiness in 1948-50 demonstrated that rice
enrichment was practical, with sticking reduction in the incidence of beriberi in the area in which enrichment was used (Saledo et al,
1950, Williams, 1956).
Moreso, a simple
procedure has been developed to fortify rice with calcium (Lee et al 1995,
Ha&iaracry ct al; lOOfi- It consist of infusing calcium salt into
the rice grain through controlled steaming technology, the fortification
process met the united state standard. Calcium fortificat^pljlce, 110-22mg/100g and
resulted in mineral washing losses of calcium.
Obstacles to the successful introduction of
rice enrichment by premix method includes the following.
* The
cost of the imported premix
* The difficulty of ensuring that the premix
is added to rice in correct proportion in the mill.
*
The slightly greater cost of enriched rice as compared with that of ordinary
rice/ which affects its sales to lower income groups.
*
Loss of added vitamins, which may occur when enriched rice is cooked
in excess water that is subsequently discarded according to current practice in some rice eating
countries.
*
Issues related to standards and analysis, part insularly of imported rice.
* Lack of knowledge about the lose of added
nutrients during storage (9^FAO 1854).
Under-milling has
been employed to retain B vitamins in milled rice, but the shift-life of
under-milled rice is shorter than that of milled rice and the product is less white (FAO
1954). Some consumers re-milled the under-milled rice to remove the rancid outer
layer and to make the rice white, with an accompanying lost of B vitamins, of B vitamins, Mille
rice has also been used for enrichment programmes for vitamin A as well as B vitamins in Thailand and Philippines (FAO 1954).