Dry fractionation for production of functional pea protein concentrates

Dry milling in combination with air classification was evaluated as an alternative to conventional wet extraction of protein from yellow field peas (Pisum sativum). Major advantages of dry fractionation are retention of native functionality of proteins and its lower energy and water use. Peas were ground by impact (ZPS50) and jet milling (AFG100) at various classifier wheel speeds to provide pea flours with different particle size distributions, protein contents and damaged starch levels. Peas were milled under various conditions to maximally disentangle starch granules from the surrounding protein bodies. The optimal milling conditions were confirmed by particle size analysis and scanning electron microscope imaging. Too extensive milling, e.g. using ultrafine impact or jet milling, resulted in very fine flours (with D0.5