NATURAL FERMENTATION OF LENTILS - INFLUENCE OF TIME, CONCENTRATION AND TEMPERATURE ON PROTEIN-CONTENT, TRYPSIN-INHIBITOR ACTIVITY AND PHENOLIC COMPOUND CONTENT

Lentil (Lens culinaris, is var. vulgaris) flour was naturally fermente d for 4 days at different temperatures (28 degrees C, 35 degrees C and 42 degrees C) and concentrations (79 g/l, 150 g/l and 221 g/l). Sampl es were analysed to establish the changes of total protein content and in vitro protein digestibility, trypsin inhibitor activity (TIA) and phenolic compound content during natural fermentation of lentils. The preparation of lentil flour suspensions to be fermented caused a sligh t increase in total protein and in vitro protein digestibility content , a decrease of TIA and a sharp decrease the tannin/catechin ratio. Du ring the whole fermentation procedure, the minimum initial lentil conc entration and temperature used (79 g/l, 28 degrees C) achieved the max imum protein content and the lowest tannin/catechin ratio. The TIA was more affected by temperature than by concentration, and a 62.5% reduc tion was observed at 42 degrees C and 79 g/l.