Optimizing the Use of High Intensity Ultrasound to Decrease Turbidity in Whey Protein Suspensions

This research employed power ultrasound (US) to decrease the turbidity of whey suspensions. US was applied using a 20 kHz generator and different power levels (3 and 15 W) for different application times (5 and 15 min) at different temperatures (20, 60 °C, and no temperature control [NTC]) to whey suspensions obtained at 4 different steps in a commercial process. The whey suspensions varied from 6.9 to 30.2% solids and 13.5 to 88% protein. This research shows an approximately 90% decrease in turbidity when US was applied to a whey suspension of 28.2% of solids containing 35.6% of protein on a dry basis. The greatest decrease in turbidity was observed when US was applied for 15 min using 15 W of electrical power at 60 °C and NTC conditions. Surprisingly, when US was used in whey suspensions containing 88.0% protein an increase in turbidity of samples was observed