Environmental Assessment of Industrially Applied Drying Technologies for the Treatment of Spirulina Platensis

Spirulina platensis is a high protein content cyanobacterium with known therapeutic properties. Its main protein Phycocyanin is currently as a functional ingredient into various food products to enhance their nutritional qualities acting as food colorant, antioxidant and emulsifier, reducing the use of synthetic additives. The post-harvest treatment of the microalga affects its content of proteins and pigments (carotenois, chlorophylls, etc.), as in the long run the environmental performance of the recovery process. In this study, industrially applied drying techniques, such as Accelerated Solar Drying (ASD) and Vacuum Drying (VD), were examined. The untreated Spirulina biomass showed the highest content in pigments and antioxidant activity, while in the case of dried biomass a significant decrease of the bioactivity was observed. ASD performed better on phycocyanin recovery, while VD showed higher total carotenoids content. Finally, ASD process showed a higher impact in all environmental impact categories, while VD’s cultivation and harvesting stage prior to drying showed significantly higher energy and carbon footprint.