Effect of selected Egyptian cooking methods on faba bean nutritive value and dietary protein utilization 2: Ability of faba bean products to support hemoglobin response in rats

Abstract

To evaluate the dietary protein utilization and iron deficiency anemia as affected by the faba bean nutrient intake, a bioassay with rats was carried out with different experimental diets containing four faba bean products (stewed beans ‘Medammis’, deep fried dough ‘Falafel’, boiled germinated beans ‘Nabet Soup’ and poured paste ‘Bissara’) widely consumed in the Middle East. Amino acid composition of all faba bean products was determined and compared to raw beans. Severe heat-processing markedly decreased some essential amino acids, especially phenylalanine, cystine, methionine and tryptophan. Protein scores were 24.6, 19.5, 29.2, 28.2 and 35.6 for raw faba beans, ‘Medammis’, ‘Falafel’, ‘Nabet Soup’ and ‘Bissara’, respectively. ‘Bissara’ possessed the highest nutritional value, since it had the lowest GDR value [Grams consumed of product to cover the daily requirements for adult man in protein (63 g) and in energy (2900 kcal)] for the limiting amino acids (L A A). As indicated by P S/150 values [Satisfaction of the daily requirements of the adult man when 150 g (one can content) are consumed of product] for L A A, i.e. methionine+cystine (lowest P S/150 value), the above-mentioned faba bean products cover about 53, 77, 77 and 97% of the daily requirements of adult man in L A A, respectively. Fecal nitrogen excretion increased and true nitrogen digestibility decreased significantly (p<0.01) with the inclusion of ‘Medammis’ in the diet. ‘Nabet Soup’ exhibited the highest true nitrogen digestibility. In contrast, the biological value of nitrogen was apparently unaffected. Highest blood hemoglobin level was found in rats fed diets containing ‘Bissara’, ‘Falafel’ and ‘Nabet Soup’, whereas the addition of ‘Medammis’ in the diet induced a significant (p<0.05) reduction in blood hemoglobin level of fed rats.