From interfacial regulation to functional enhancement: Microwave pretreatment optimized rice bran oil body stability and nobiletin delivery.

To clarify the regulatory effect of microwave pretreatment on the stability of rice bran oil body (RBOB) and its practical value, this study systematically investigated the impact of different microwave power pretreatments on the yield rate, rheological behavior, microstructure and multispectral structure of RBOB. It also systematically explored the regulatory mechanism of this pretreatment strategy on the RBOB stability. The results showed that microwave pretreatment significantly affected the extraction efficiency and physicochemical properties of RBOB. Among them, 300 W was confirmed as the optimal microwave power. Under this power, the yield rate (76.42%) of RBOB significantly enhanced, the rheological behavior exhibited typical shear thinning characteristics and the viscoelasticity was ascended. The microscopic structure presented that oil body (OB) particles were uniformly dispersed and the interface was clear and intact. The multi-spectral characteristics revealed that the interface protein conformation was moderately stretched and relaxed, forming an interface protein membrane with both mechanical flexibility and molecular looseness, thereby effectively improving the physical stability and dispersibility of OB. Based on RBOB pretreated with optimal microwave power, a comprehensive evaluation was conducted on the encapsulation performance, oxidative stability and in vitro release behavior of nobiletin. The results revealed that this approach significantly enhanced the encapsulation efficiency (80.75%) and loading capacity (4.0373 mg/g) of nobiletin, effectively delayed its oxidative degradation, and regulated its in vitro release rate (20.53%) to achieve sustained-release properties and significantly improve its bioaccessibility. Furthermore, it offers a theoretical basis and technical support for the resource utilisation of RBOB and the development of functional products.