The CO2 micro algae biorefinery

Aim and goal

The D-Factory aims to set a world benchmark for a sustainable biorefinery based on biomass from the halophilic microalgae Dunaliella.

Challenge

Dunaliella is currently cultivated commercially for its high β-carotene content. The resulting product is a powder consisting of spray-dried Dunaliella cells and therefore a mixture which largely consists not only of carotenoids but also proteins, carbohydrates, fats and minerals. While the bio-refinery concept to be implemented within this project will go beyond the production of these crude products, it will also result in a number of extracts and extract-rich fractions with different specifications in terms of both compounds and purity. Thus, the challenge of the formulators assessing and evaluating the best possible uses of these extracts, will be not only to test and benchmark the properties of the actual individual components present in Dunaliella but also those of different extract-rich fractions produced as a result of economically viable separation processes.

Solution

Formulation know-how for specific high-value added products applications as well as a good understanding of current possibilities, challenges and limitations of the most important Dunaliella compounds and their properties was the basis for a successful outcome.

Effect

After processing biomass using supercritical CO2 and solvents for 9-cis b-carotene, the natural colorants produced as a by-product are well-suited for food markets that are growing to meet demand from the Lifestyles of Health and Sustainability (LOHAS) demographic and other food sectors, and extracts have been formulated in a variety of ways for use in different beverage-type applications. The defatted powder after processing also shows great promise in tests as a feed additive and also as a protein-rich bulking agent in fish sausages, and the individual starch, polar lipids and protein fractions have been processed as food additives, emulsifiers, and in gluten-free protein-enriched bread.