Experimental Design and Optimization of Ultrasound Treatment:Functional and Physical Properties of Sonicated Ice Cream Model Mixtures

Abstract

The aim of this study was to determine the effect of high power ultrasound on functional properties of ice-cream model mixtures. Mixture composed of sucrose, glucose, whole milk powder, whey protein concentrates (WPC) and distilled water was ultrasonically treated according to different parameters. Amplitude of ultrasounds, percentage of WPC in the sample and time of treatment are the three variables considered. Effect of ultrasound parameters on rheological properties (measurement of coefficient of consistency), thermal properties (measurement of initial freezing point) and foaming properties (measurement of maximal foam capacity) was observed. Experiment was designed using model called Central Composite Design (CCD) permitting to consider the significant factors for each property, and results were analyzed and process was optimized through response surface methodology-RSM. Through study, optimal conditions of ultrasound treatment (amplitude, treatment time and percentage of WPC) by which experiment should be performed were obtained. The factor “percentage of WPC” is significant from a rheological and thermal point of view. Regarding foaming properties, the significant factor that is to say affecting most the value of the maximum foam capacity is the duration of ultrasound treatment.