Chemical engineers will play a pivotal role in ensuring the ongoing success of one of Australia's largest industries following a grant awarded to a major research center there that focuses on Australia's dairy industry.[pullquote]
Australia's national dairy herd of 1.6 million cows produces just shy of 10 million liters (2.6 million gallons) of milk a year. According to Dairy Australia, Southbank, Victoria, this is worth A$4 billion at the farm gate or A$12 billion at wholesale. (The Australian dollar currently is at parity with the U.S. dollar.) With 40,000 employees, dairy production is the country's third largest rural industry.
A substantial part of this production is used in the manufacture of 342,000 tons of cheese, 148,500 tons of butter and 359,600 tons of milk powders. These powders are worth in excess of A$1 billion — with spray-dried dairy products accounting for over 50% of exports.
Milk powder production is the most-energy-intensive dairy manufacturing process, with the Australian manufacturers under increasing pressure to improve efficiencies and reduce the cost of bulk powder production.
And it is these powders that chemical engineers in the department of chemical engineering at Monash University, Victoria, are focusing their thoughts.
A chemical engineering project titled "Breakthrough technologies for energy-efficient manufacture of dairy powders" has just won a four-year A$320,000 grant from the Australian Research Council (ARC) Linkage project.
The grant is specifically aimed at supporting collaborative research and development (R&D) projects between higher education researchers and other parts of the national innovation system, which are undertaken to acquire new knowledge, and which involve risk or innovation.
In this case, professor Xiao Dong Chen and Dr. Cordelia Selomulya from the department of chemical engineering at Monash are working in collaboration with Dairy Innovation Australia Limited (DIAL), Werribee, Victoria, to revolutionize dairy manufacturing processes in Australia.
DIAL leads R&D in the areas of food technology, engineering, microbiology, health and nutrition for the Australian dairy industry. In providing cutting-edge solutions in these areas it partners and funds research with private research organizations, research institutes, universities and government bodies.
For his part, professor Dong Chen specializes in a wide variety of large-scale food-related processing issues, including: powder technology, drying (spray drying in particular), falling film evaporation, frying, powder agglomeration, lumping and caking, powder functionality, heat exchanger fouling, cleaning, new coatings for anti-fouling purposes, heat and mass transfer, and evaporation processes.
Selomulya's specialization includes functional (nano) materials, characterization and functionalization of smart materials for applications in medical diagnostics and therapeutics, food, national security, and the environment. Selomulya also focuses on low-temperature synthesis of bioactive composites for the manufacturing of high-value products such as controlled-release particles for pharmaceutical and functional food applications.
"This project will address how the industry can achieve tremendous gain in energy savings while reducing environmental costs through a combination of lower temperature spray drying and more efficient evaporation processes in generating high quality powders from high solid liquids," explains Selomulya.
The innovation is also applicable to food and pharmaceutical industries where spray and fluidized-bed drying are integral parts of the manufacturing process. The project will train graduates to be able to make a high-level contribution to these industries.
The outcomes of this project should lead to significant change for the dairy industry in Australia. In particular, the enormous cost-saving and environmental benefits due to a more efficient drying process should boost the international competitiveness of the industry.
"The ARC funding will enable the research group at Monash to recruit high quality postgraduate students to the project, while working closely with the dairy industry. It will also be used to extend the pilot-scale facility for the dairy research at Monash University," Selomulya adds.
In other dairy-related work at Monash, professor Dong Chen has been tackling the general lack of information on large-scale operation of an immobilized enzyme reactor with realistic production capacity for the enzymatic hydrolysis of lactose by ß-galactosidase. This is one of the most popular technologies used to produce lactose-reduced milk and related dairy products for consumption by lactose-intolerant people.
A pilot-scale 10-liter packed-bed reactor using ß-galactosidase immobilized on cotton fabric has served to hydrolyze lactose in whole milk, both in batch and continuous runs. About 95% of lactose conversion was achieved after two hours of batch operation, while productivity during continuous operation was found to vary with residence time of the milk. Investigations are still underway.
Seán Ottewell is Chemical Processing's Editor at Large. You can e-mail him at [email protected].