Ultrasound project to manipulate dairy processing
industry capable of slashing production costs and enabling new,
high-value products by manipulating ingredients during processing,
writes Chris Mercer.
The ground-breaking project, undertaken by scientists in Australia, aims to improve processing control and cut costs in common processes like heat stabilisation.
Dr Muthupandian Ashokkumar, one of the researchers, said: "High-frequency sound waves can be used to generate chemical and physical interactions in milk components, which may then provide us with an opportunity to modify the processing characteristics and end-use functionality of dairy ingredients."
Ashokkumar said the technique could help producers develop new high-value dairy products more cheaply - giving Australia a leading position in heat-stable and new functional ingredients.
"By harnessing this technology to modulate the heat stability of dairy proteins, for example, we hope to greatly improve the effectiveness and significantly reduce the cost of common industrial processes used in the manufacture of high-value dairy products."
Ashokkumar, of the University of Melbourne, has received AUS$375,000 (€233,600) to investigate the use of ultrasound in dairy processing, in collaboration with Food Science Australia and the Dairy Ingredients Group of Australia.
The work is also being funded by a $3.5m government grant designed to explore the potential of ultrasound and other emerging technologies in food processing. The money was awarded to a consortium of researchers from the University of Melbourne, Food Science Australia, Swinburne University of Technology and CSIRO Plant Industry.
"Already the technique has been used in a range of processes from the decomposition of organic wastes to the enhancement of drug absorption, though its use in the food industry in still in a developmental stage," said Ashokkumar.
The whole process is called sonochemistry and has proved to have great potential for manipulating the structures of molecules, and the chemical interactions, that occur in liquids.
How It Works
? Ultra-high frequency sound waves (ultrasound) are passed through a liquid, generating a series of chemical and physical reactions.
? Tiny micro-bubbles begin to form. These bubbles then grow and shrink as each wave of sound passes through until eventually they grow to a certain size and implode.
? The imploded bubbles leave localised areas of heat. This generates a sequence of reactions that begins with the production of radicals - pairs or groups of atoms bound together but incapable of surviving in this form, and looking for another atom or molecule to attach to.
? This may be used to change the characteristics of components in the milk, such as proteins.
Hygiene benefits of ultrasound
Ashokkumar and a colleague, Dr Sandra Kentish, have also found that ultrasound can make the process of ultrafiltration faster and more hygienic.
Ultrafiltration uses porous membranes to siphon off whey, a by-product of cheese production, and separate different proteins according to their size. Some proteins recovered by this method can be re-used in food processing.
However, the pores often get clogged and must be cleaned and sanitised after each batch.
The researchers found that ultrasound could remove these proteins in only 10 minutes.
