How power ultrasound helps you improve processing

10 December 2021 | Robbie McGill, Process Technologist

As many companies look to improve the efficiency of their processes and reduce energy and water usage, ultrasound has emerged as an assistive technology for a wide variety of applications in the food and drink industry. Previously having been proven in laboratory and pilot scale operations, power ultrasound now has a proven track record in industrial settings, actively providing reduced operating costs, product wastage and processing times on a variety of products. Ultrasound has been used to assist the processing for a wide variety of applications in the food and drink industry, even in processes with high throughputs.

Ultrasound mainly affects products with a phenomenon called cavitation, where micro bubbles are generated which rapidly expand and shrink until they reach a critical point and implode. This implosion can create local temperatures of up to 5000K and pressure of up to 1000 bar, which can lead to many processing benefits. In freezing, cavitation can lead to increased heat transfer, allowing for faster freezing of products and the generation of smaller ice crystals avoiding excess damage that may occur with traditional freezing. This technology is already available for the industry.

Increased mass transfer as a result of ultrasound can also be used for extraction applications such as the extraction of compounds from teas and coffees, protein from insects and even dry hopping in the brewing of beer, an application that has been explored in the latest published R&D report.

The acoustic oscillations from the air-coupled ultrasound can be used in defoaming applications such as the production of soft drinks. It works by causing the liquid to drain from the bubbles in the foam until they become unstable and collapse. This technology has proven benefits such as reduced rejects, increased filling speed, reduced packaging contamination and increased filling temperature.

There are a multitude of applications the ultrasound can be used in:

Extraction
De-foaming
Mass transfer
Microbial inactivation
Heat transfer
Viscosity modification
Freezing/Crystallisation

As part of our New technologies member funded research project, Campden BRI has published a New technology bulletin detailing the many applications that ultrasound can be employed in on an industrial scale as well as the benefits this can provide.

In addition, Campden BRI has also published an R&D report exploring the use of ultrasound in brewing applications. This report explores the extraction and mass transfer applications of ultrasound that can be applied in the brewing industry, studying the hydration of barley and impacts of accelerating dry hopping extraction and its effects on the quality of the resultant beer.

New technologies research

As part of the member funded research project, Campden BRI research emerging technologies of interest to the food and drink industry. Recently, this has led to the power ultrasound research project and its applications for the industry.

If you are a member of Campden BRI, you can access the current status of this project, the New technology bulletin and R&D report associated to it featuring three case studies of ultrasound applied in pilot scale brewing.

We’re always looking for feedback on technologies to explore or review. Submit your suggestions to newtechnologies@campdenbri.co.uk so we can investigate technologies that interest you.