Sweet Kangaroo Island discovery for sour beers

By Shannon Pearce

Researchers from the University of Adelaide have found new species of lactic acid bacteria on Kangaroo Island that could be used in the fermentation of wine, ciders and sour beers.

The team discovered five new species in samples taken from insects, including meat ants and cockroaches, and flowers around KI bee hives at Kangaroo Island Ciders, Clifford’s Honey Farms, Living Honey, De Tong Ling, Island Beehive and near Sunrise on Falie accommodation.

PhD candidate Scott Oliphant from the University of Adelaide’s School of Agriculture, Food and Wine said they chose Kangaroo Island “due to its unique microclimates, undisturbed and biodiverse plant life and beekeeping industry with intact biosecurity protocols”.

“This type of bacteria like to live in sugar-rich places. So, honey having tons of sugar, a good place to look for lactic acid bacteria is around hives.”

The samples were collected shortly before the devastating bushfires in the summer of 2019-20.

“Some of the microbes we assessed were from Flinders Chase National Park apiaries, which were destroyed in those bushfires,” Oliphant said

He said besides taking samples from flowers, the team looked at the guts of insects because they harbour a core set of lactic acid bacteria.

“It’s basically that they have these bacteria as symbionts inside of them. It’s part of their gut microbiome,” Oliphant said.

“Bees, wasps, sawflies and ants exchanges these microorganisms when they visit different types of flowers.”

Testing on the new bacteria has found that a number of the Kangaroo Island bacteria are able to sour wort for sour beer production.

“We have one isolate there that we’re working on trying to see its industrial potential. That’s been sent overseas. They’re doing some more testing on it too to see its applicability,” Oliphant said.

There are also hopes that one of the bacteria can perform malolactic fermentation, a process that removes malic acid from wine.

“We’re working on a project with the microbrewery on campus,” Oliphant said.

“Hopefully, we’ll get some larger scale studies soon and actually have some consumer testing in the next couple of months to see the utility of the strains in making a sour beer, and if consumers actually find that preferable.”

Lactic acid has been harnessed for yoghurt, wine and beer production for millennia, but the newly discovered species of bacteria could offer something new.

“They might have different properties or impart different flavours than what’s currently on the market or currently being cultivated,” Oliphant said.

The project was funded by Wine Australia in partnership with the University of Adelaide, The Australian Research Council Training Centre for Innovative Wine Production and wine and yeast company BioLaffort.

The research was published in the International Journal of Systematic and Evolutionary Microbiology.

This article originally appeared at The Lead SA.