Application of Ultrasound in Proteins: Physicochemical, Structural Changes, and Functional Properties with Emphasis on Foaming Properties

Proteins have the ability to form foam, which is a system consisting of a gas phase dispersed within a continuous phase, either liquid or solid. In certain types of food, the incorporation of gas is important for maintaining quality and sensory attributes. However, foam is a thermodynamically unstable system, and its stabilization is a highly researched area. In recent years, there has been growing interest in the application of ultrasound not only to improve foaming properties, but also to alter physicochemical and structural characteristics of proteins, making it an environmentally friendly and versatile technology. Ultrasound can enhance formation and stability by inducing conformational changes through the cavitation phenomenon. However, the benefits of this technology depend on the inherent characteristics of the proteins and the conditions applied during its use, such as frequency, time, amplitude, energy, protein concentration, volume, and medium conditions. This review aims to explore how ultrasound influences the physicochemical properties, induces structural modifications, and consequently enhances functional characteristics such as foaming capacity.