Ione Christensen’s starter, one of the oldest strains around, is being added to a collection in a Belgian ‘library’ with 84 samples from 20 countries

Every Saturday night for the last sixty years, Ione Christensen has followed the same routine to prepare waffles for breakfast the following morning: she measures out two cups of flour and two cups of warm water, then she reaches into her fridge to bring out her sourdough starter.

“It’s a family pet, if you will,” she said from her home in Canada’s Yukon territory.

Like any pet, the starter needs to be constantly fed – in this case, with flour and water.

But the spongy blend of wild yeast and bacteria has far outlived any ordinary pet: at 120 years, the sourdough is much older than Christensen, who is 84.

Earlier this month, Christensen baked for a new guest: Karl De Smedt, a Belgian baker, who scours the globe for new sourdough strains to add to his “library” in Belgium.

So far, the collection in the town of St Vith contains 84 samples in refrigerated glass jars from 20 countries, including Mexico, Greece and Japan.

De Smedt’s archive is meant to both showcase geographically diverse varieties of yeast and preserve a growing collection for future generations to study.

Facebook Twitter Pinterest Ione Christensen with her parents in 1939. Christensen knows the starter travelled with her great-grandfather around 1897, but she is unsure of its exact origins. Photograph: Supplied

“The taste of Ione’s waffles was amazing. I am from Belgium and she was making Belgian waffles,” said De Smedt. “They were very light, but at the same time, I had a couple of them and they filled my stomach for hours.”

In baking, a starter is a culture of yeast and bacteria that converts starch molecules into sugars. During this process, the yeast also produces carbon dioxide, which in turn helps the bread rise. It is a critical – if under-appreciated – component of baking, said De Smedt.

“For 5,000 years, everybody on earth who wanted to make bread had to use sourdough,” he said. In modern baking, yeast is extracted, meaning bakers don’t need to feed their starter every few hours: “They were slaves to their sourdough,” he says.

De Smedt will bring a sample of Christensen’s starter – labeled “106” – back to the library and also provide some to Italian researchers, in order for them to sequence and study the DNA profile of the sourdough.

His visit to Christensen’s home in Whitehorse is part of a journey from Seattle to Alaska and the Yukon, where he is tracing a culinary legacy inadvertently established by gold prospectors.

Christensen knows the starter travelled with her great-grandfather around 1897, but she is unsure of its exact origins.

Small lumps of yeast and bacteria, often found tucked in the flour sacks of prospectors, were critical during the Klondike Gold Rush.

Because most food froze, flour – and the starter – became so important to prospectors that over time, a person from the Yukon became known as a “sourdough”.

Dating strains is difficult, says De Smedt, but Christensen’s is among the oldest in his collection.

Christensen laughs at the prospect that the starter, with its newfound fame, might eclipse her own impressive list of accomplishments – including first female mayor of Whitehorse, Commissioner of Yukon and Canadian senator.

Facebook Twitter Pinterest Christensen as Commissioner of Yukon in 1979. She laughs at the prospect that the starter might eclipse her impressive list of accomplishments, including first female mayor of Whitehorse, Commissioner of Yukon and Canadian senator. Photograph: Supplied

“I’m not looking for legacy. The Yukon is a small community. When there’s something to be done – there were no men’s jobs or ladies jobs – there were just jobs. And if you were there and it needed to be done, you did it.”

Before she bakes, Christensen is careful to set aside a small amount of the mixture, in order to feed it back to the starter in the jar. Without doing so, the legacy of the sourdough would come to an end.

That the starter will find a new home among other sourdoughs – and in history – is a pleasure in itself for Christensen.

“I’m quite proud, because I feel I’m sort of a keeper of a Yukon legend,” says Chirstensen. “I don’t feel it’s just my sourdough. It’s the Yukon’s sourdough.”

