Development of protein isolation methods from microalgae

Developing cost-effective and sustainable methods to harvest water-soluble proteins from microalgae biomass for applications in human and animal food products.

This will be achieved by:

  • Adapting existing bio-refinery technologies to mildly separate and isolate water-soluble proteins from microalgae, while maintaining protein functionality.

Background

Algae protein to increase algae biomass value

To develop cost-effective algae processes, the value of algae biomass has to increase. This can be achieved by utilizing as many potentially useful algae biomass components as possible. Protein, and especially water-soluble protein, is one of the promising ingredients of algae. It may account for half of total algae biomass and can be applied in human and animal food products. Consequently, algae protein could replace imported and unsustainable tropical soya proteins.  

Extraction of Rubisco protein from algae cells

The water-soluble protein Rubisco has many applications for use in food products, such as a natural foam-stabilizer and emulsifier. The soluble protein fraction in algae may contain as much as 70 percent Rubisco. In many algae, Rubisco is protected by starch structures, making extraction extra challenging.

Methods

Development of water-soluble algae protein extraction methods

Innovative bio-refinery methods will be tested and adapted for water-soluble protein extraction in algae biomass, with emphasis on extraction of Rubisco. Bio-refinery methods should not jeopardize protein functionality and this requires mild technologies. For example, the algae cell wall will be cracked using ‘pulse electric field’ methods, that punctures the cell wall, but may leave the cell contents intact. Mild technologies to remove the protective starch structures from Rubisco proteins will be developed. The water soluble protein fraction, containing Rubisco, will be separated from more hydrophobic proteins using a mild two-phase extraction liquid (ionic liquid extraction).