Development and performance optimization of capillary bridge-driven oleogels using cellulose nanocrystals

Abstract

In recent years, replacing saturated fats with liquid oils rich in unsaturated fatty acids has gained significant attention. However, practical applications still face challenges, such as high costs, complex processes, and suboptimal performance. To address these challenges, this study proposed a strategy for constructing capillary bridge-driven oleogels using cellulose nanocrystals (CNC) and systematically investigated the key factors and mechanisms influencing gel formation and performance. The results showed that both the CNC mass fraction (φ) and secondary fluid saturation (S) significantly affected oleogels. Specifically, S significantly influenced oleogel formation, with stable oleogels formed at S = 0.10–0.20 and φ = 0.20–0.30 maintaining their structure after 24 h of inverted storage. CLSM results demonstrated that an optimal S level (S = 0.15) drove the oleogel into the funicular state, thereby enhancing stability. The φ mainly regulated oleogel performance, improving structural stability, viscosity, and modulus as it increased. At S = 0.15 and φ = 0.30, the oil holding capacity of oleogel reached 90.23 %. Further studies showed that the ionic strength and pH of the aqueous phase significantly impacted the regulation of oleogel rheological properties. The addition of salt ions increased network cross-linking, while extreme pH levels might weaken hydrogen bonding. This study proposed a simple and efficient liquid oil structuring solution with excellent performance, providing valuable theoretical and technical support for the design and application of oleogels in the food industry.