Improving the cryoprotective effect of antifreeze proteins from Daucus carota on plant-based meat by eliminating N-glycosylation.

As a novel animal meat alternative, plant-based meat (PBM) frequently suffers from quality problems as a result of freeze-thaw cycles in commercial transportation and household storage. There is a need to reduce the deterioration of PBM attributes, such as water holding capacity, as a result of these freeze-thaw cycles. In this study, Daucus carota antifreeze protein (DcAFP) and its deglycosylated mutant DcAFP-N294G were heterologously expressed in Komagataella phaffii X33. The effects of pretreatment with recombinant AFPs (rAFPs) on the microstructure, rheological properties, water mobility, and water distribution of PBM were assessed. The rDcAFP-N294G-treated PBM samples had superior viscoelasticity and water distribution features compared to the rDcAFP-treated group because the complex N-linked oligosaccharides did not interfere with the binding of rAFPs to ice molecules. In addition, rAFP pretreatment resulted in a smoother and flatter surface of the high-moisture protein extrudate matrix compared to the commercial cryoprotectant trehalose. Deglycosylated DcAFP has potential applications as a new effective cryoprotectant in meat alternatives.