Tribo-electrostatic separation of yellow pea and its optimization based on milling types and screen sizes

A tribo-electrostatic separation was developed to produce protein concentrates from yellow pea flour. A mixed -level full factorial experiment followed by a multiple linear regression model was developed to assess the impacts of airflow rate, plate voltage, milling type, and screen size as operating factors on protein content, separation efficiency, and yield of the protein-enriched concentrates. Except for plate voltage, all factors showed significant impacts on protein content. The interaction of plate voltage and milling screen size was significant in protein content. Plate voltage was the only main effect statistically impacting protein separation efficiency; however, polynomial interactions of flow rate with plate voltage and flow rate with milling type and screen size were significant. The optimal parameters were laminar flow at +/- 6.5 kV electric field strength using pin-milled flour at the smallest tested milling screen size, which resulted in protein content of 57.1% and separation efficiency of 62%. Theoretical predictions agreed with experimental data.

Automated summary

A tribo-electrostatic separation method was developed for producing protein concentrates from yellow pea flour. A full factorial experiment and a multiple linear regression model were used to assess the impact of operating factors on protein content, separation efficiency, and yield. The results showed that airflow rate, milling type, and screen size significantly affected protein content, while plate voltage mainly influenced protein separation efficiency. The optimal parameters were laminar flow at +/- 6.5 kV electric field strength using pin-milled flour at the smallest tested screen size, resulting in a protein content of 57.1% and separation efficiency of 62%. Theoretical predictions matched experimental data.