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We tested the effects of several processing methods on the nutritional value of faba beans. Nutritional assessment was based on chemical analyses of legume protein content and on the digestive and metabolic utilization in rats. Protein content in Vicia faba (V. faba) was 28%, and the supply of essential amino acids, except for sulfur-containing acids, was sufficient to cover the rat's nutritional requirements. Food intake was significantly lower in animals fed with raw faba beans than in the control group given the casein diet. We attribute this to the deficient levels of some amino acids and the presence of antinutritional factors (α-galactosides and tannins) in faba beans. All processing methods except heating under pressure increased food intake. The digestive utilization of V. faba protein was high, although lower than that of the casein diet. This may be related to the presence of protease inhibitors and tannins in faba beans. Nitrogen retention was similar in control animals and rats fed with raw beans; however, growth was faster in the former group, probably because of the better balance in amino acids supplied by this diet. Soaking in basic medium with or without subsequent cooking greatly increased growth, probably as a result of greater nitrogen retention and utilization of carbohydrates, which may have been stored as fat. Keywords: Faba beans; nutritive utilization; processing; digestive utilization; metabolic utilization

An experimental animal model was used to investigate whether processing improved the nutritive utilization of phytic acid phosphorus in faba beans. Phytic acid had been considered an antinutritional factor because of its ability of chelate minerals and impede their absorption and because of the limited capacity of monogastric species to hydrolyze and utilize phosphorus from this molecule. This is of particular significance in legumes, where a large portion of phosphorus is in the form of phytic acid. Heating and soaking in acid solution followed by cooking led to large decreases in phytic acid. Soaking reduced phosphorus content (15.4%).Processing made part of the phytic acid phosphorus available, as suggested by our finding that absorbed P was greater than P from sources other than phytic acid. The lower phosphorus content in bone and blood in rats led to a significantly lower phosphorus balance in animals fed faba beans. Keywords: Faba beans; nutritive utilization; phosphorus; processing; phytic acid; inositol hexaphosphate

Changes in the trypsin inhibitor activity (TIA) of faba beans (Vicia faba L. Major) were investigated after beans were soaked in distilled water, citric acid, and sodium bicarbonate solutions. The soaking solution was discarded. The effect of cookingsdiscarding both soaking and cooking solutionsswas also studied. Finally, a dry-heating process was examined. Soaking treatment produced a slight decrease of trypsin inhibitor activity. Cooking the presoaked seeds brought about the total or partial removal of TIA, depending on the soaking solution used. TIA was partially removed after dryheating. Trypsin inhibitor activity analyses were completed with 28-day biological trials for raw and dry-heated faba beans. For 21 and 28 days of experimental time food intake, protein intake, and weight gain were similar for rats fed raw and dry-heated faba beans. However, after 28 days protein efficiency ratio (PER) and food transformation index (FTI) improved in rats fed dry-heated faba beans compared with those fed raw faba beans. This was related to lower TIA values found in dry-heated faba beans.