The coffee industry has always been hot for technology. The forerunner to the modern espresso machine was invented in 1884, only to be replaced by a string of rival designs touting superior pressure, faster extraction and more consistent heat.

After 130 years, this arms race hasn’t abated. Today’s cafes are proving grounds for numerous gadgets, from new-model espresso machines to automatic tampers and milk-dispensing taps. Some of these toys turn out to be expensive fads, while others become essential to keeping up with the competition.

But in 2020, the next frontier isn’t a newfangled grinder or brewer. It’s an everyday appliance that pre-dates the espresso machine by 50 years: the freezer. Some of Australia’s top roasters and cafe operators are finding it increasingly useful for serving coffee at its best.

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Nolan Hirte founded Melbourne-based roaster Proud Mary. In addition to three cafes in Melbourne, the company now runs a cafe in Portland, Oregon and has another on the way in Austin, Texas.

Hirte has spent a decade trying to predict how many espressos his baristas will pull in a given week so that he can roast the appropriate amount of beans. When he gets it right, the coffee is served eight days after roasting – what he sees as the ideal amount of time to vent carbon dioxide and unpleasant flavours. But just as often, the beans could be three, five or 14 days old, outside their prime.

Hirte, a confident tradesperson, last year drilled three fist-sized holes in the bottom of a small bar freezer at Proud Mary in Portland. The cafe’s grinders sit underneath, with their hoppers projecting up inside, a set-up later repeated at Aunty Peg’s in Melbourne. The espresso roasts at both locations are now aged for eight days, then vacuum-sealed and deep-frozen to arrest the ageing process. When beans are needed for service, they’re moved directly to the hoppers.

“Once it’s in there, it’s exposed,” Hirte says. “It’s not ideal. There’s air around it and there’s potential moisture in the freezer.” Still, as a fridge extends the life of milk, this system ensures each new batch of coffee pretty much stays at its prime until it’s used. Studies have also shown that frozen beans grind more evenly than room-temperature beans, resulting in a cleaner, more focused cup.

“The goal for us is not to store coffee in the freezer for long periods of time,” Hirte says. “We’re just trying to create consistency with what we do.”

In contrast, three years ago, Canberra-based roaster Ona Coffee began vacuum-freezing unground beans into individual serves for the express purpose of long-term storage. At its cafe in Marrickville, in Sydney’s inner west, a leather-bound “freezer menu” lists 20 to 30 reserve coffees. Later this year the same concept will be rolled out at Ona’s forthcoming cafe in Brunswick, in Melbourne’s inner north. Though preceded internationally by 1914 Coffee Company in Squamish, Canada, and George Howell Coffee in Boston, USA, Ona is thus far the only player in Australia running such a program.

Coffee in this back catalogue ranges from $4.50 to $34 a cup and is mostly served black, meaning it appeals to a relatively small number of customers. But Ona’s training manager, Hugh Kelly, believes there’s a knock-on effect for everyone. Roasters and other industry professionals can easily become desensitised to overly tannic or astringent coffee over time, he says. Freezing samples of past work allows them to continually benchmark new against old and ultimately improve quality at the wholesale level.

Matt Perger, the founder of Barista Hustle, a coffee training hub and R&D lab associated with Melbourne roaster St Ali, sees the freezer as coffee’s answer to Coravin, the vacuum-sealed machine that allows single glasses of wine to be extracted from a bottle without introducing oxygen and spoiling the remainder.

“It opens up the possibility of spreading out the enjoyment over a longer period of time,” Perger says. “Which is excellent because with coffee, it’s very ephemeral. It’s good, and then it’s bad.”

Coffee stored properly, the way Ona does it, won’t suffer freezer burn and can last for several years without a discernible drop in quality. Thus temperature control, freezing or otherwise, may soon become integrated into the entire coffee supply chain, as in the meat, dairy, fruit and vegetable industries.

“Now that we’ve unlocked this ability to freeze coffee, everyone is going to be clapping and saying, ‘Hey, we can have more expensive coffee and enjoy it for longer’,” Perger says. But he’s less excited about this than the possibility of roasting happening in the countries where coffee is actually grown.

“With frozen logistics and the fact that we can trust coffee is preserved when frozen, why isn’t more value going to be sent down the chain, towards the farmers, towards the countries that have a lower GDP than ours?” he says. “We should be sending much, much, much more of the value. That’s a question I really want to start exploring.”

This story first appeared in print issue 29.