Protein Shifting and Enrichment with the use of Dry Grinding and Classifying

The global food supply chain is undergoing significant changes. With the world's population growing, the demand for food, especially proteins, is increasing. This demand cannot be met solely by animal proteins due to the extensive land required for livestock and water usage. Additionally, consumers are increasingly demanding sustainable production methods.

Therefore, alternative protein sources obtained from plants, mushrooms, insects as well algae or bacteria fermented biomass are crucial for future needs and are intensively investigated nowadays. A well-established source are plant-based proteins. Focusing on the production of meat alternatives, protein isolates from soy with a protein content > 80 % are the means of choice as major ingredient therefore – mostly obtained through diverse wet extraction methods.

But due to ongoing developments in dry fractionation technologies and seed breeding, the process has become an energy-efficient method to produce high-quality protein concentrates with significant lower plant investment as wet technologies. The goal is to achieve a protein-rich fraction with a significantly higher protein content than the original material through dry grinding and air classification.

Starting mostly from dehulled pea, mung or faba bean, the resulting protein fractions are achieving protein concentration generally between 55 and 70 % - just mechanical treated with full functionality and native state of the protein. Without question, an economical yield of the fraction of 25 – 40 % (dm) should be generally achieved. Main influencing factors are species, moisture and protein starting level of each legume.

To understand the main principle of the protein shifting process, we must look on the cotyledon of a suitable legume, like pea: The size difference between big, elastic starch bodies (40 µm) and small protein granules (3 -10 µm) is the essential condition of the raw material!