Konjac glucomannan enhances the freeze-thaw stability of Pickering emulsions with different oil phases stabilized by double-induced whey protein isolate nanoparticles and influences their digestion characteristics.

Firstly, the present study was conducted to characterize the freeze-thaw stability of Pickering emulsions (PEs) stabilized by double-induced whey protein isolation nanoparticles (DI-WPINPs), using corn oil, soybean oil, and flaxseed oil phases as distinct oil phases, while also elucidating the underlying mechanisms involved in this process. Results revealed that DI-WPINPs-stabilized PEs with the addition of 0.04% konjac glucomannan (KGM) maintained excellent freeze-thaw stability across different oil phases. Incorporating KGM did not significantly alter the particle size of DI-WPINPs, but it did reduce the magnitude of their negative charge. Meanwhile, KGM caused a notable reduction in the particle size of PEs. The interaction between KGM and DI-WPINPs resulted in a compact polygonal droplet structure for PEs, whereas those stabilized solely by DI-WPINPs displayed loose spherical particles. KGM also exerted remarkable effects on PEs: it modified their rheological properties, lowered interfacial tension and their freezing point. Secondly, the effect of KGM on the digestion properties of DI-WPINPs-stabilized PEs was explored. Notably, during the 120-min small intestine digestion process, KGM reduced the particle size and delayed the release of free fatty acids from DI-WPINPs-stabilized PEs. Overall, this study contributes to expanding the application range of PEs in the food industry and offers insights for designing them as carriers for liposoluble bioactive substances.