Nutritional evaluation of ethanol-extracted lentil flours

Lentil, flours were extracted with 80% ethanol at 25 and 50 degreesC for 1, 2, or 3 h. The various nitrogen fractions, soluble carbohydrates, three am ino acids (Lys, His, and Tyr), available lysine, protein digestibility, and vitamins B-1 and B-2 were analyzed to evaluate the effect of extraction. E xtraction resulted in an increase in the total nitrogen content of the extr acted flours, with extraction temperature affecting the nature of the nitro gen (protein or nonprotein) content. There was also a large reduction in th e oligosaccharides of the raffinose family, although the effect of temperat ure was appreciable only in the case of stachyose. There was hardly any eff ect on the concentrations of the amino acids analyzed or on protein digesti bility; however, a positive correlation between protein digestibility and t he available lysine was recorded in the samples. The vitamin B-1 and B-2 co ntents underwent variable decreases depending on extraction temperature.