Winery waste valorisation as microalgae culture medium: A step forward for food circular economy

Wastewater is one of the critical environmental problems worldwide. In this study, the circular economy concept was applied to winery wastewater that has been considered as a rich source of nutrients for growing edible microalgae to produce a high value protein product. To this end, Chlorella vulgaris and Arthrospira platensis were co-cultured. The effects of processing parameters on the microalgae yield and protein recovery were examined. Different microalgae growth systems: open pond, column and tubular photobioreactor were used for obtaining more than two grams of dry weight biomass per liter. The protein fraction was extracted and recovered by ultrasound-assisted extraction. The image analysis shows that wastewater strongly affected the intracellular components concentration, cell morphology, and resistivity to cell rupture. The results of our study demonstrate that it is viable to use microalgae to substantially reduce the pollutant impact of the wastewater and produce high value products such as proteins.