Upon ultrasonic treatment at 20 kHz, protein aggregates in a dairy whey solution were broken down. In addition, when sonication was applied to a heated solution of denatured and aggregated proteins, there was a dramatic reduction in viscosity and aggregate size, which was maintained after re-heating. This observed heat stability may be due to shear forces that are induced by acoustic cavitation. To determine whether high shear mixing or homogenisation is able to cause similar effects to that of acoustic cavitation, sonication, high shear mixing and homogenisation were performed on 5 wt% whey protein concentrate solutions at identical energy density levels, which was based on the power drawn in each system.Homogenisation provided similar particle size and viscosity reductions as sonication while high shear mixing was less efficient in decreasing particle size. Cavitation was shown to be absent in both the mixing and homogenisation configurations, indicating that the shear forces generated are responsible for the observed particle size and viscosity reduction. In addition, heat stability was achieved in all systems indicating that a combination of heat treatment and any method that generates high shear forces can be used to improve the heat stability of whey proteins.

The production of whey protein concentrate powders is often limited by the fouling of the ultrafiltration membranes and the low heat stability of the whey protein solutions. Ultrasonic treatment of whey solutions has previously been shown to break down protein aggregates and improve heat stability. This study investigates the use of ultrasound as a pre-treatment step to improve downstream ultrafiltration performance. Results show that sonication alone alleviated membrane fouling to a small extent. However, the use of ultrasound following heat exposure reduced membrane pore blockage and growth of the foulant cake greatly, relative to heat exposure in the absence of ultrasound. The extent of changes to pore blockage and cake growth was greater at higher solids concentration. In all cases, the protein concentration in the permeate remained unchanged. This work has the potential to reduce energy requirements in the ultrafiltration of whey as feed pre-treatment by both ultrasound and the combination of heat and ultrasound produced a lower viscosity feed solution.

Integrating knowledge across disciplines has been shown to be a challenging, and yet it is a necessary skill that university students need to develop. Students who are able to connect different concepts, perspectives, and angles of a given topic are generally more engaged and have better understanding. However, designing lesson plans or assignments that integrate knowledge across disciplines is a challenge to most instructors. This paper describes our effort to provide an interdisciplinary and independent assignment that couples topics from a Physical Chemistry course with skills taught in an Introductory Computing course. It was shown that such an interdisciplinary assignment, though done independently, can help to boost students' learning. However, it helps only in the understanding of certain aspects of the topics. We present the design of the assignment and the lessons learned for other instructors willing to adopt this kind of interdisciplinary approach.

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