Prefeasibility project of a dry process for bitter quinoa varieties, based on the application of a spouted bed
Quinoa is an Andean natural resource with exceptional nutritional properties. Its cultivation is encouraged with the purpose of contributing to food security and generating exports, in order to improve the quality of life of the inhabitants of one of the most impoverished and ecologically fragile areas of Bolivia.
Quinoa varieties most used for domestic consumption and export, contain between 0,6 and 3,0% of saponins in the episperm of the grains, which are bitter alkaloids that must be removed before eating.
The most advanced processes of debittering of the quinoa grains consist of three steps: a soft scarification not to destroy the grain, followed by a wash with agitation and several rinses, and a drying. Washing and rinsing consume significant amounts of water (5 - 14 m3 ton of product), which is a scarce resource in the region where quinoa is processed, and generate effluents contaminated with saponins which are toxic for cold-blooded species.
The UPB proposed the development of an optimized dry process, through the novel use of a spouted bed reactor.The study corresponding to the laboratory research phase has been developed on the basic operating characteristics of a Fluidized Type Bed (LFTS), used in the dry removal of saponins from 2 bitter varieties of royal quinoa provided by two beneficiary companies. located in the towns of Salinas de Garci Mendoza and Uyuni in the departments of Oruro and Potosí, respectively.
The most important results of the study are:
Saponin removal - Analysis of experimental design results
• The most prominent factors in saponin removal are bed diameter and nozzle diameter, followed by variety. Bed height has very little effect.
• Lower concentrations of saponins are obtained from the two varieties studied (all below the acceptable value for human consumption for benefited quinoa) when quinoa is processed in the smallest diameter bed with the smallest diameter mouthpiece and with the highest height. bedding. On the other hand, white real quinoa is processed better than yellow real quinoa.
• Minimum saponin values (0 - 0.04%) are reached in the ranges from 1.4 to 2.2 mm for the nozzle diameter and 7.5 to 12.5 cm for the bed diameter and a bed height 12.5 cm.
• None of the factors studied: nozzle diameter, bed diameter, bed height and variety has a significant effect on the percentage of proteins at a confidence level of 95%.
• The percentage of protein in the grains increases with the removal of saponins.
• Unit consumption of electrical energy is high when using a compressor
• The recovery of saponins is total
As a general conclusion, it can be affirmed that the configuration of the dispensing type fluidized bed that does not use water is ideal for the removal of saponins from different varieties of bitter quinoa on a laboratory scale (homemade scale).
References about the project: ccquiroga@upb.edu
* The project had the financing of the Strategic Research Project of Bolivia PIEB
Responsible:
Carla Quiroga Ledezma, Ph. D.
E-mail: ccquiroga@upb.edu
Researchers:
Ramiro Escalera Vázquez, Ph. D.
Ing. MSc. Luis Artega W
Ing. Francisco Montaño
Mgr. Ricardo Nogales
Important_Link: Strategic Research Program in Bolivia - PIEB
