New research suggests converting the Australian dairy industry's whey waste into a valuable food product is more feasible than many realise, with significant potential for industry-wide change.
Researcher at the University of Adelaide, Jack Hetherington
Whey is a by-product of cheese manufacturing and one of the largest sources of food loss and waste in the Australian dairy sector, and the country's food industry more broadly. It's the liquid that remains after milk is curdled and strained during cheese and yoghurt production.
Jack Hetherington, from the University of Adelaide's Centre for Global Food and Resources, says while there are multiple high-value reuse options - such as protein powders, alcoholic beverages (beer or vodka), kombucha, and cooking stocks - his new report reveals the sector has not fully capitalised on this valuable by-product.
"A key finding from my research is that only a small number of cheese manufacturers, across all production scales, have adopted innovative technologies and business models to upcycle whey into high-value products," Hetherington says.
"The broader sector has been slow to adopt these practices due to a lack of clear incentives, persistent and unique barriers, and an absence of enabling conditions. Despite this, there is significant potential for widespread change in a relatively short period, particularly if collaborative efforts receive greater support."
The dairy sector significantly contributes to Australia's overall food loss and waste, accounting for an estimated 14.9 per cent. According to Dairy Australia, approximately half of this dairy waste is whey.
As part of a mixed-methods study, funded by the University of Adelaide, the End Food Waste Cooperative Research Centre and Australia's national science agency CSIRO, Hetherington interviewed large and small cheese manufacturers across Australia to understand where their whey goes and what factors influence their decisions to repurpose it.
Hetherington explored four potential business models and collaboration strategies to reduce whey waste: in-house processing; third-party partnerships, where whey is sold or given to another business for processing; joint ventures, where manufacturers collaborate to achieve scale and share processing infrastructure; and focal companies, where existing whey processors accept whey from other cheesemakers, increasing throughput and reducing waste.
"All four models ultimately achieve the same goal: transforming whey waste into a valuable food product," Hetherington says.
"Manufacturers already processing whey should consider accepting whey from nearby cheesemakers, which would demonstrate industry leadership, reduce waste, and generate additional revenue. One business I spoke to makes more money from whey than cheese - there's great potential for success.
"For retail businesses, such as supermarkets, shifting procurement policies towards whey-based alternatives would also incentivise change, while consumers should consider opting for whey-based products."
Regulatory hurdles could be streamlined to make it easier for cheesemakers and other sectors to seize these opportunities.
"While regulations like waste levies incentivise change, other policies - such as food safety regulations and alcohol taxation - can act as barriers," Hetherington says.
"Finding ways to improve the circularity of our food system could unlock economic benefits for the industry and enable us to produce more with less. This will require both new forms of collaboration and the right incentives to help businesses overcome barriers and invest in change. Dealing with food loss and waste is a complex, ever-evolving issue, with no single solution."
