Trametes versicolor as a Natural Source of Bioactive Compounds for the Production of Whey Protein Films with Functional Properties: A Holistic Approach to Valorize Cheese Whey.

Purpose: Cheese whey (CW) protein and lactose fractions were individually valorized in the direction of functional food development, employing a newly isolated Trametes versicolor strain from Kefalonia Island (Greece). Methods: T. versicolor growth was evaluated on solid-state fermentations, using potato dextrose agar (PDA), whereas submerged fermentations were employed under static and agitated conditions, using pure lactose and CW-lactose fraction as fermentation media. Subsequently, whey protein fraction was utilized for edible films production supplemented by the freeze-dried fungal biomass. Edible films properties were further characterized concerning their thickness, water-related properties, protein composition and antioxidant capacity. Results: T. versicolor presented a high growth rate (7.5 mm/day) on PDA. Submerged fermentations showed that T. versicolor assimilated lactose; however a slower consumption rate was observed in agitated cultures, compared to static cultures. The highest biomass production of 26 g/L was achieved in the CW-based medium, showing a protein content of 19.8%. Enrichment of whey protein films by T. versicolor biomass presented lower water vapor permeability and higher antioxidant capacity, compared to control films. Conclusion: The development of a novel CW biorefinery scheme was shown in this study, employing medicinal mushrooms for biomass production to create added-value food products towards a zero-food waste strategy. [ABSTRACT FROM AUTHOR]