Impact of the maturity stage at harvest on the nutritional value of four pulses

Pulses have a high nutritional value. However, their limiting amount of sulfur-containing amino acids and their content in antinutritional compounds negatively affect its qualities. It is well known that the nutritional value of pulses varies according to several parameters including the maturity stage at harvest. Thus, the harvest at different maturity stages could be of interest to modulate and enhance the nutritional value of pulses. Since there is very limited data available on this research topic, this project aims to study the physicochemical composition of four pulses at two maturity stages at harvest.

Borlotti beans, red beans, black beans and chickpeas at the fresh (FMS) and the dry maturity stage (DMS) were characterized for their dry matter (DM), mineral, fat, protein, trypsin inhibitor and α-galactosides contents as well as their protein and amino acid profiles. The evolution of the albumin: globulin ratios was also studied.

On a dry basis and compared to the DMS, the FMS borlotti beans contained more protein and α-galactosides. The FMS red beans were characterized by their high content in α-galactosides. The FMS black beans contained more mineral, fat, essential amino acids and α-galactosides compared to the DMS. Finally, the FMS chickpeas contained a higher albumin: globulin ratio, more trypsin inhibitors and less α-galactosides compared to the DMS. Depending on the pulse, the maturity stage at harvest affected the nutritional profile and the most interesting differences were notably found in the antinutritional factor content. Consequently, the harvest at different stages of maturity could be of great interest to generate pulses with optimized nutritional values.