Protein from pea mutants as a co‐product in starch separation – Isolates from wet and dry separation: yield,composition and solubility

The dry separation behaviour of cotyledon material of certain pea genotypes (wild type and 5r mutants) with different metabolic background in starch biosynthesis allowed satisfying protein recovery only with smooth seeded genotypes. Structural effects and protein distribution (starch granule size distribution, protein in non‐starch part) play an important role. According to expectations protein composition remained unaltered during dry separation procedures. Independent of genotypes used the applied conditions in wet separation allowed to recover just 50% of seed proteins while approximately 10% got lost with fibres and 40% with unspecified process water streams. Globular vicilins remained dissolved during iso‐electric precipitation and were discarded with waste water streams. The solubility of isolates was rather low under alkaline conditions, even for the round seeded cv. Odalett (0.4 to 0.7% dry substance).