IMPACT OF PROCESSING ON FE DIALYZABILITY FROM BEAN (PHASEOLUS-VULGARIS L)

The influence of dehulling and cooking on in-vitro Fe dialysability fr om two varieties of Phaseolus vulgaris L. (mottled and white beans) wa s investigated. Fe and seed constituents (phytate, tannin, dietary fib re) were differently distributed between hull and cotyledon. Fe dialys ability from mottled bean was 2.5%, from white bean 3.6%. Dehulling si gnificantly decreased Fe dialysability (36%, P < 0.025) from both vari eties. Cooking significantly reduced Fe dialysability from mottled bea n (59%, P < 0.025), whereas in white bean no modifications were detect ed. On the other hand, cooking positively influenced Fe dialysability from cotyledon: compared with the raw samples, both varieties showed a significant increase (54%, P < 0.005) in Fe dialysability. This study showed that localization of both Fe and some seed constituents in see d affected Fe dialysability. Changes in food constituents (i.e. degree of protein digestion) account for the modifications in Fe dialysabili ty subsequent to cooking.