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 preblended powder enrichment, mixes includes, thiamins riboflavins, niacin, niacinamind, ferric orthophosphate (white iron) ferrous sulphate (yellow iron) or reduced iron which is relatively water insoluble and white in colour (Hffpaur 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 enrichement 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 nutrient levels are the same as those of brown rice. The multi nutrient enriched rice is blended with rice at ratio of 1:200 only 10percent 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 Philippines 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 Lec et al (1995). It consist of infusing calcium salt into the rice grain through controlled steaming technology, the fortification process met the united state standard. calcium fortified rice, 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 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).
Figure 1. Flow chart of Rice processes
Whole grain rice
Cleaning
Hulling
Sieving /Aspiration
Pearling /Milling
Aspiration
White rice
Polishing
Packaging
Packaged rice
Source: Okaka 1997
Related Posts: AGRICULTURE
Be the first to comment