Recent advances in antibacterial food preservation using soy protein isolate-stabilized essential oil nanoemulsions

With increasing demand for safe, natural, and sustainable food preservation, soy protein isolate (SPI)-based nanoemulsions have emerged as promising carriers for bioactive compounds such as essential oils (EOs). Several techniques, including high-pressure homogenization, microfluidization, ultrasonication, spontaneous emulsification, phase inversion temperature (PIT), and phase inversion composition (PIC), have been employed to fabricate SPI-based EO nanoemulsions with desirable droplets (50–200 nm) and improved physicochemical stability (up to 30–60 days). Mechanistic insights into stabilization strategies, including SPI secondary structure transitions (e.g., β-sheet enrichment), covalent/non-covalent SPI–polyphenol interactions, and Pickering-like interfacial structuring, are critically examined. This review systematically categorized SPI-based emulsifiers, elucidated the functional characteristics of SPI-stabilized EO nanoemulsions, and discussed the key factors influencing their stability, biofunctionality, and applications in meat, fruits, and dairy matrices. Moreover, this review uniquely connects formulation parameters to food-specific outcomes, and discusses challenges such as EO volatility, sensory impact, and safety evaluation. Finally, regulatory considerations and future perspectives on improving delivery efficacy, stability, and nutritional compatibility are addressed. This comprehensive synthesis offers a practical framework for the design and food industry application of SPI-based nanoemulsions.