Preparation and characterisation of palm-based tocotrienol-carotenoid emulsion stabilised by hemp protein isolate-ginsenoside emulsifier

The present work examined the effects of combining hemp protein isolate (HPI) and ginsenosides (GS) on emulsion stability. Emulsifiers at various HPI-to-GS ratios (1:0, 0.75:0.25, 0.5:0.5, 0.25:0.75, and 0:1) were evaluated. FT-IR spectroscopy revealed that GS formed hydrogen bonds with HPI, and modified its secondary structure, reducing β-sheet content and exposing hydrophobic regions. The mixed emulsifier showed significantly improved emulsifying activity, stability, and antioxidant capacity compared to pure HPI (p < 0.05). The emulsion prepared using a mixed emulsifier at 0.5:0.5 HPI to GS ratio exhibited smaller particle sizes (253.6 ± 4.3 nm), higher zeta potentials (-42.7 ± 1.0 mV), improved encapsulation efficiency (98.89%), and a more uniform particle size distribution, all of which contributed to stability enhancement. Additionally, the emulsions prepared with mixed emulsifier showed good storage stability (14 d) and thermal stability, but demonstrated poor resistant to ionic strength and freeze-thaw cycles. Overall, HPI-GS complexes showed promise as effective emulsifiers for producing stable emulsions.