PHYTIC ACID IN RELATION TO MINERALS AVAILABILITY AT DIFFERENT EXTRACTION RATES OF WHEAT FLOUR

Abstract

Minerals are one of the nutrient groups vital to the human health and the deficiencies of minerals remain a momentous public health problem in many parts of the world, predominantly in developing and under developing countries where imperfection to vitamin A, iron, iodine and other micronutrients leads to adverse health disorders. The phytic acid has serious health concerns as it decreases the bioavailability of many essential minerals by interacting with multivalent cations and proteins to form complexes that may be insoluble or otherwise unavailable under physiologic conditions. This project is designed to increase the availability of minerals in flour with high and low extraction rates. In the present study three wheat varieties namely AARI-11, Faisalabad-08 and Lasani-08 at different extraction rates were characterized with special reference to physico-chemical analysis. The grains of each wheat variety was tempered and then milled through Quadrumate Senior Mill and whole wheat flour was formed through Udy Cyclon Mill. The results showed that significant variations were found in physico- chemical analysis and mineral profile of different wheat varieties. The test weight and thousand kernel weight ranged from 73.79 to 76.97 kg/hL and 40.71 to 43.85 grams, respectively, among different wheat varieties. The chemical parameters including moisture, ash, protein, fat and fiber contents were affected significantly by the wheat varieties and the extraction rates. The results exhibited variations among different extraction rates flour. It was revealed that 70% extraction rates flour possessed the highest moisture (12.36%), wet and dry gluten contents (27.56% and 10.58%, respectively) where as the whole wheat flour exhibited the highest ash (1.66%), fat (2.48%), protein (12.84%) and fiber (1.54%) contents. Rheological characteristics i.e. Farinographic and Mixographic studies of the flour were significantly affected by the different extraction rates and wheat varieties. The whole wheat flour exhibited the highest mineral contents as compared to the flour with low extraction rates. Hydrochloric acid extractability of minerals was increased significantly with the increase in extraction rates and significantly affected by the extraction rates and wheat varieties. Low phytate flour was prepared through autoclaving, fermentation and enzymatic degradation of phytic acid. The phytic acid content was significantly affected by the different processing treatments. The highest phytic acid content was found in whole wheat flour. Sensory parameters of chapattis and naan demonstrated non significant (P>0.05) effect among the wheat varieties where as significant effect was observed among the extraction rates. The efficacy study was conceded and degraded phytic acid samples were fed to rats for the analysis of serum biochemical profile. Two year study i.e. 2011 and 2012 was carried out to check the efficiency of the product and then results of both years were compared. It was concluded that fermented flour has higher value in the bioavailability of the minerals