Effect of four plant oils on the stability of high internal phase Pickering emulsions stabilized by ovalbumin-tannic acid complex

The poor interfacial stability of protein-stabilized high internal phase Pickering emulsions (HIPEs) is a major hurdle to realize their practical applications in food processing. The emulsifying stability is not only related to the protein itself, but also dependent upon the oil phases. In this study, four plant-based oils were studied to understand their respective effects on the interfacial stability of HIPEs prepared by ovalbumin (OVA) and ovalbumin-tannic acid complex (OVA-TA). Our findings revealed that the interfacial activities were closely related to the physicochemical properties of the oil phase, such as the number of carbon‑carbon double bonds in the unsaturated fatty acids, melting point, and polarity. The emulsifying abilities were ranked as palm oil > soybean oil > olive oil > perilla oil. OVA-TA stabilized HIPEs exhibited excellent emulsifying stability compared with free OVA stabilized ones. This work provided a unique insight into understanding the interfacial stabilization mechanisms for protein-stabilized HIPEs with different kinds of oil phases.