Polyphenol-enriched ethylcellulose oleogels with rice bran oil: properties, oxidative stability, and application in Harbin red sausage.

Ethylcellulose (EC)-based oleogels offer a promising alternative to animal fats, yet their lower oxidative stability remains a challenge. In order to explore the effects of polyphenols on the structure, physicochemical properties, and oxidative stability of oleogels, EC-based oleogels loading ferulic acid (FA), rosemary extract (RE), and resveratrol (RES) at concentrations of 0.1%, 0.3%, and 0.5% were prepared. Meanwhile, RES-loaded oleogel was employed as a pork fat replacer to prepare Harbin red sausage at substitution levels of 40% and 80% in this study. X-ray diffractometer, infrared spectroscopy, and thermogravimetric analyses revealed that the addition of polyphenols promoted a more compact and stable network microstructure of the oleogels, probably driven by physical interactions. All polyphenols, especially FA, significantly decreased the lightness of the oleogels. Texture and rheological results demonstrated that polyphenols improved mechanical strength and viscoelasticity, polyphenols-loaded oleogels also possessed higher oil binding capacity (OBC). The oleogels had considerable antioxidant activity after loaded with polyphenols. Meanwhile, the oxidative stability of oleogels was significantly improved by all three polyphenols in a concentration-dependent manner. Notably, RES was most effective in retarding primary oxidation, while FA showed superior suppression of secondary oxidation products. The substitution with RES (0.3%)-loaded oleogel decreased the lightness and hardness of sausage, partially alleviated hardness loss. E-nose distinguished sausages with different substitution ratios, while E-tongue showed no clear separation among groups. These findings demonstrate that polyphenols can enhance the mechanical strength, OBC, and oxidative stability of EC-based oleogels, while also noting trade-offs in color and texture.