Nutrients and non-nutrients composition and in vitro starch digestibility of five Algerian legume seed flours

Lentil (Lens culinarius L.), faba bean (Vicia faba L.), chick pea (Cicer arietinum L.), common bean (Phaseolus vulgaris L.) and yellow pea (Pisum sativum L.) seeds produced in Algeria were evaluated for physico-chemical properties, chemical composition, in vitro starch digestibility and phytate and protease inhibitor content. Significant differences were observed in bulk density (0.794-1.293 g/mL), hydration capacity (0.030-0.362 g/seed), hydration index (0.704-0.937), swelling capacity (0.032-0.353 mL/seed) and swelling index (0.488-1.087). The crude protein content ranged between 20.10 and 26.37%. V. faba and P. sativum seed flours had comparatively higher total non-starch polysaccharides (NSP) contents, with mean values of 172.26 and 192.51 mg/g, respectively. Among the minerals of nutritional interest, seed meals were rich in potassium (838.56-285.43 mg/100g) and magnesium (46.20-77.33 mg/100g). Significant differences were determined in in vitro starch digestibility. V. faba flour was hydrolysed more slowly than the other legumes. The amount of slowly digestible starch (SDS) in V. faba flour was the highest among these legume flours, but also had the lowest resistant starch (RS) content. Trypsin and chymotrypsin inhibitor contents of the different samples ranged from 2.27 to 16.22 TIU/g, and from 1.77 to 27.15 CIU/mg, respectively. Protease inhibitor content was significantly higher in common bean, while pea and faba bean showed the lowest TIU/mg and CIU/mg content. The total amino acids content was 190.42- 223.33 mg/g, and the total essential amino acids content was 74.82-84.77 mg/g. The tannin content of faba beans and peas was the lowest, while the amount in common beans was the highest. The potential nutritional implications of these results are discussed. The present work demonstrated that chick pea, lentil, faba bean, common bean and pea whole flours have a great potential as nutritious and healthy food ingredients.