Integral Wheat Flour Based Biscuits as Sources of Phosphorus in Everyday Nutrition

Eight experimental integral wheat fl our based biscuits were prepared and investigated for total and bioavailable phosphorus content. Results were compared to the values obtained for classic white wheat fl our based biscuits in order to asses the impact of implantation of bran, different integral raw materials and fibers on the total phosphorus content and its availability. Since a study was conducted in the view of current trends of the excessive intake of this element in most of the developed countries, we expressed results obtained for total phosphorus content as percentages of allocated RDA values. Total phosphorus was determined by an offi cial AOAC method (AOAC 2001) and its bioavailability by an in vitro enzymatic method (Schwedt et al. 1998). Total phosphorus content of investigated samples ranged from 1.093 g kg-1 (biscuit based on type 500 wheat fl our) to 2.987 g kg-1 (biscuit enriched with integral wheat fl our and amaranth). Phosphorus availability was the highest in biscuit based on type 500 wheat fl our, as expected (86.1 %), and the lowest in the sample enriched with amaranth fl our (53.0 %), due to a very high phytic acid content. Considering revealed values of total phosphorus content and its bioavailability, we concluded that the richest source of this important macroelement was the sample enriched with soy flour providing 1.671 g kg-1 of available phosphorus.