The Effect of Pretreatment of Ultrasound Waves on the Functional Characteristics of Freeze-dried Egg White Powder

Egg plays an important role in the food processing due to the high nutritional value, functional properties and participation in nonenzymatic browning reactions to enhance the aroma and taste of the products. In this study, the effect of ultrasound power (0, 100, 200, 300, and 400 kW) on physicochemical and functional properties such as solubility, foaming properties, emulsifying properties, water and oil absorption capacity, viscosity, and particle size of freeze dried egg white powder was investigated in a completely randomized design with a 95% confidence level. The results showed that the foaming capacity of egg white powder ultrasonicated with the power of 300 and 400 kW increased compared to the control. The emulsifying activity and foam stability of the egg white powder ultrasonicated did not change compared to the control. Ultrasound and increasing its power had no significant effect on the solubility and viscosity of egg white powder. Egg white powder particle size was reduced at higher ultrasound powers (400 kW). The highest water absorption capacity and the lowest oil absorption capacity were related to egg white powder ultrasonicated with a power of 100 kW. Overall, the use of ultrasound was effective in improving the functional properties of egg white powder. In general, the application of high power ultrasound (300 and 400 kW) increased the ability to produce foam. Increasing the ultrasound power from 100 to 400 kW caused a significant reduction in the size of egg white powder particles.