Once, the only profit to be made from a bullock was from its body fat and new farming districts were built around the production of the greasy substance, ideal for a range of end uses.
The product was only marginally regarded, other more lucrative parts of the beast more favoured. But right now, animal fat is worth more than ever as it features in the distillation of future fuel production.
"Historically when the price reached $1000 a tonne we would get very excited and sell as far forward as possible," says Jeremy Millar, Casino Food Coop commercial supply chain manager.
"But before Christmas the price peaked at $2700/t. It has come off a bit, but remains extraordinarily high."
The pandemic worked in tallow's favour, as food shops shut their doors and availability dwindled for second-hand fryer oil, traditionally the go-to for biodiesel.
For that reason the bids went up from repeat buyers while more recently the US government has upped that ante on biodiesel production and so there have been two buyers at the rail.
"They both want tallow for the same purpose - and it's clean and pure," says Mr Millar.
"Tallow fits well into the green economy."
With the US sales encouraged by government-funded climate credits, there could be concern for the long-term viability of biodiesel as a stand-alone product, however, the program has been going for longer than President Biden has been in office.
"And Trump didn't change it, so it must be working," says Mr Millar.
Meanwhile, demand for biodiesel in 2023 is predicted to jump eight per cent while the International Energy Agency predicts a 20pc upswing for green diesel between 2020 and 2027.
As such, demand is expected to maintain upwards price pressure on tallow.
Sadly, the cosmetics industry is not in this market, having left the bidding back when the stuff was only $600/t.
Mr Millar recalls a time when a Singaporean shutdown caused the price of tallow to crash overnight - around 2015-16 - but the soap and cosmetics buyers flooded in.
"In the last 12 months the US has really stepped into that space and put a lot of competitive pressure on tallow," he says.
Industrial demand for new fuel from fat
A key player in the tallow space, and the dominant price maker, is refinery group Neste, with a plant in Singapore; part of a larger Finnish group that prides itself on sustainable fuel production from waste.
The company sources a range of source materials, but animal fat waste is an important raw material for Neste, belonging to its top three largest raw material categories used in its production, together with used cooking oil and various wastes and residues from vegetable oils processing.
Typical biodiesel is made by combining carboxylic acid with alcohol to reduce the viscosity of fat.
At Neste, the process is more refined with the company's NEXBTLE technology, using hydrotreatment to remove ammonia, hydrogen sulphide and water.
Unstable compounds that clog injectors convert to stable compounds with no damage to the distillate itself. In fact, hydroprocessing of the triglycerides that give fat its structure produces a diesel fuel chemically identical to its petroleum-derived relation, says a company spokesperson.
"The result is a very pure hydrocarbon," she says.
The high quality fuel that results is a straight substitute for fossil diesel but comes with a 100pc renewable rating.
"Unlike conventional biodiesels, our product is also suitable for very low temperatures, while there is also no deterioration in quality or water accumulation, which can promote microbial growth," the spokesperson says.
"Neste uses only sustainably-produced renewable raw materials that fully meet the sustainability requirements specified in the legislation in our key markets. We source renewable raw materials only from traceable sources, select our renewable raw material suppliers carefully and monitor their performance.
"All the renewable raw materials that we have in our portfolio provide significant greenhouse gas emissions savings when refined into renewable products: Our renewable products help reduce greenhouse gas emissions by 50 to 95 per cent over the life cycle of the product compared to similar products from fossil origins."