Effects of different germination conditions on the contents of free protein and non-protein amino acids of commercial legumes

Seeds of beans, lentils and peas were germinated for 2, 4 and 6 days, either under continuous light or continuous dark, and the free amino acids analysed by HPLC. The effects of germination on the free protein amino acids (FPA) and non-protein amino acids (FNPA) depended on the type of legumes and on the processing conditions. After germination of beans, histidine, glutamate, glycine, arginine, tyrosine and tryptophan contents decreased while, in lentils and peas, FPA increased after germination. Light germination gave the highest amounts of FPA in beans and lentils, but the lowest in peas. The FNPA changed markedly with germination. In beans, germination produced a reduction of α-amino adipic acid and an increase of GABA (γ-aminobutyric acid). All FNPA increased in lentils and peas. Light germination resulted in the highest α-amino adipic acid contents in beans, and the highest value of taurine in lentils. The highest FNPA content was found in peas after dark germination.