Stability, microstructural and rheological properties of camellia oil emulsion stabilized by sodium caseinate with konjac glucomannan

Abstract Camellia oil is highly regarded for its rich nutritional value; however, its inherent instability limits its application in food processing. To enhance the stability of camellia oil emulsions, this study introduced konjac glucomannan (KGM) and systematically investigated its effects on the physical stability, rheological properties, and microstructure of sodium caseinate-stabilized camellia oil O/W emulsions. The emulsion droplet size and emulsification index were firstly analysed, and the results showed that high KGM concentration induced a decrease in droplet size and an increase in emulsion stability. With the increase in oil–water mass ratio (0.2–0.7), the droplet size gradually increased and was uniformly spherical, and the emulsification index of the emulsions decreased with the addition of high KGM level, which prolonged the storage time of the emulsions. The rheology and microstructure showed that with the increase in KGM concentration, film-like connections were formed between droplets, and a more solid, rigid gel network was formed inside the emulsion, which effectively trapped the emulsified droplets and further increased the stability of the emulsion. This study provides a new theoretical basis for optimizing the stability of camellia oil emulsions by KGM and broadens the application prospects of camellia oil in the food industry.