Research Progress on Plant Polyphenols Encapsulated by Emulsion Systems and Its Application in Food Industry

Plant polyphenols are a class of plant secondary metabolites containing several phenolic hydroxyl groups in their molecular structure, which have physiological properties such as anti-inflammatory, anticancer, antibacterial, etc., and can be used as excellent dietary supplements. However, some of the polyphenols are poorly stabilized, and they are prone to degradation during food production, processing, and storage, so it is necessary to use encapsulation technology to improve their stability and maintain their activity at the same time. The emulsion possesses the characteristics of stability and versatility with the potential to encapsulate and protect plant polyphenols. This paper firstly analyzes the properties of plant polyphenols and the underlying reasons for their limited applications, further discusses the encapsulation effect of different types of emulsions (normal emulsion, microemulsion, nanoemulsion, Pickering emulsion, multilayer emulsion and emulsion gel, etc.) on polyphenols, and finally summarizes the current status of polyphenol emulsion encapsulation systems in the food industry such as meat, fruits and vegetables, ice cream, bakery, and beverage, etc., and provides an overview of polyphenol emulsions in the future preparation direction and its development direction in the food field. This paper can provide some reference for the application of plant polyphenol emulsion encapsulation system in the future food industry.