New Zealand’s first-ever wild beer yeast harvested from the banks of the Rangitīkei River

Froth Technologies co-founders Ryan Carville (left) and Simon Cooke have created the first wild strain of brewing yeast in New Zealand, thanks to yeast from the banks of the Rangitīkei River.

A trip to the banks of the Rangitīkei River has resulted in the creation of New Zealand’s first-ever wild beer yeast.

Lower Hutt-based beer lab Froth Technologies is releasing the beer isolate, named Wilding, with the first commercial beer brewed with the yeast set to debut later in November.

Froth Technologies co-owner Simon Cooke said the discovery came from a desire to find a wild strain of yeast, something the company had never worked with.

“The strains that we grow here in our yeast factory currently have been domesticated, in that they’ve been in breweries for hundreds of years in parts of the world, so they’re quite tame,” Cooke said.

Only one of the 1500 kinds of yeast microbes is useful for brewing so, to better the chances of success, the lab team went to a raft of remote environments across Aotearoa, including the banks of the Rangitīkei River near Hunterville.

Their adventures netted 400 yeast isolates taken from 45 samples and, of these, Rangitīkei’s Wilding is the first of the batch to be used in beer production.

Wilding was found using an air trap, which Cooke said involved leaving an open jar of unfermented beer on the riverbank overnight with a cloth filter on top to allow any microbes in the air to ferment in the brew.

“It’s kind of just intentionally spoiling a beer to see what’s in there,” he said.

Flavour-wise, he said pilot beers fermented from Wilding were quite dry, meaning the yeast consumed most of the sugar in the drink.

“There’s a unique gene found in wild yeast which helps it ferment really dry,” Cooke said.

The wild nature of the strain gave the beer a funkier taste than those brewed with domesticated yeast.

“Domestic strains are referred to as being quite clean so they’re quite subtle in what they offer to a beer, while this wild strain... you can expect a bit more character from the yeast.”

The wild beer developed fruity-tasting esters with hints of pear and banana, while also having a warm, dry spice to it.

“Then the strong, dry fermentation gives a nice dry finish with a lager-like quality,” Cooke said.

The first commercial beer, also called Wilding, to be brewed by Emerson’s Brewery with the strain will be launched on Friday, November 10.

Emerson’s head brewer Mason Pratt said Froth Technologies approached them to work with the yeast and the brewery jumped at the opportunity.

“Yeasts are as distinctive as fingerprints, so using a yeast with origins in the unspoiled New Zealand wilderness that’s wild in character and completely unique is exciting,” Pratt said.

The brewery deliberately dialled down the brew’s hops to accentuate the yeast’s unique flavour.

“The result is reminiscent of Belgian-style ale with spiced aromas, banana richness, but with a lager-like clean finish and a unique blend of sweet and dry.”

Other commercial brewers have been sent the Wilding yeast to see what they can make from it.

With its flavour profile, Cooke thought the strand might remind brewers of Belgian-style beers like Saison, as they were brewed with similar techniques and also often used wild yeast.

However, the lab was encouraging brewers to experiment and come up with something new.

“We’re just encouraging them to create something inherently, uniquely Kiwi.”

Froth Technologies is currently crowdfunding a release of homebrew yeast pouches via PledgeMe, for which Wilding will also be an option.

Finn Williams is a multimedia journalist for the Whanganui Chronicle. He joined the Chronicle in early 2022 and regularly covers stories about business, events and emergencies. He also enjoys writing opinion columns on whatever interests him.