Sustainable approaches to utilization of lactoferrin and dissolved air flotation dairy by-products for high-value applications

The dairy industry produces large quantities of waste, including by-products of dissolved air flotation (DAF) sludge and lactoferrin front fraction. Protein- and lipid-rich DAF sludge is produced during the removal of fats, oils, and suspended solids from wastewater. The lactoferrin front fraction is a by-product of extraction of lactoferrin and contains residual proteins and compounds. Currently, these streams are under-utilized and are typically disposed of. This review highlights the current and future potential of repurposing these side streams into high-value products. These side streams have been applied as media for microbial growth and use in precision fermentation, and could serve as sources for high-value proteins, such as growth factors, or peptones. We identify gaps to guide future development of applications with economic and environmental benefits. Research into these applications will support sustainability and innovation in the global dairy industry by enabling processing of waste into valuable resources.