Effects of two debittering processes on the alkaloid content and quality characteristics of lupin (Lupinus mutabilis Sweet)

Background: The presence of quinolizidine alkaloids (QAs) in the species Lupinus mutabilis Sweet limits the expansion of its consumption and use, despite its high protein content. Therefore, the objective of this research was to determine the effect of two thermal treatments, aqueous (ATT) and saline (STT) on QAs and total protein contents, as well as on the texture (fracturability and hardness), the attributes of the visual perception Hue (H*), Luminosity (L*) and chromatism (C*) and grain size in three lupin varieties (INIAP‐450, INIAP‐451 and Criollo). In addition, the water consumption of each treatment was measured. Results: The debittering process with the ATT helped to concentrate the total nitrogen by 560 g kg‐1 and decreased the grain hardness to 2037gf in the Criollo variety, while the chromatic parameters H* and C* increased in the three varieties. The STT was more efficient than the ATT in terms of the time required and the volume of water used to reduce the QAs to safe levels for consumption (2.5‐3.5 g kg‐1). The size of the grain increased to 4 times its original size; the luminosity L* decreased during cooking to a value of 41.49 in the Criollo variety and then increased to 57.42 during grain washing. Conclusions: the STT was advisable for lupin debittering, although the extent of the effect was dependent on the variety.

The authors acknowledge the Cooperative Program for the Regional Agricultural Technology Fund (FONTAGRO) (Project FTG/RF-14893-RG, 2016-2018) and financial support from the Inter-American Development Bank (BID). (Project FTG/RF-14893-RG, 2016-2018) and Spanish Ministry of Science, Innovation and Universities (RTI2018-339 095919-B-C21), the European Regional Development Fund (FEDER).

Peer reviewed