6533b7dbfe1ef96bd1270874

RESEARCH PRODUCT

Effects of legume processing on calcium, iron and zinc contents and dialysabilities

subject

description

Legumes are a good source of calcium, iron and zinc, but are also a source of phytates and dietary fibre components that can negatively affect the bioavailability of these minerals. To estimate the latter, an in vitro dialysis method can be applied that gives the dialysability of a mineral as an estimate of its availability for absorption. Calcium, iron and zinc contents and dialysabilities in three legumes (beans, chickpeas and lentils) and the effects of cooking treatments and industrial processing on these parameters were studied. Beans had the highest calcium content (1.54 g kg -1 dry matter (DM)) and chickpeas the lowest iron content (46.9mg kg -1 DM), whilst the zinc contents were similar in all three raw legumes (33.7-36.9 mg kg -1 DM). Traditional and microwave cooking reduced the mineral contents by 9.7-36.4% for calcium, 14.2-31% for iron and 11.1-28.9% for zinc. The dialysabilities of calcium with respect to the values for the raw products were also reduced by these cooking techniques. Industrially processed legumes had higher dialysabilities of calcium, iron and zinc than traditionally or microwave cooked legumes. Les legumes sont une bonne source de calcium, de fer et de zinc mais aussi de phytates et de fibres alimentaires qui peuvent affecter la biodisponibilite de ces mineraux. Pour evaluer ces derniers, une methode de dialyse in vitro peut etre utilisee, elle donne la capacite de dialyse d'un mineral comme estimation de sa capacite d'absorption. Les teneurs en calcium, en fer et en zinc sont etudiees dans 3 legumes (haricots blancs, pois chiches et lentilles) ainsi que les effets des traitements de cuisson. Les resultats montrent que les procedes industriels sur les legumes engendrent de meilleures capacites de dialyse de ces elements que les procedes de cuisson traditionnels ou par microondes.