There are bakers, and then there are sourdough bakers. A curious breed, all their own.
The most passionate among them enjoy an oddly close relationship with a living, amorphous blob, sometimes generations old, that requires warmth and constant feeding - about every eight hours.
This is the sourdough starter, or levain: a bubbling cluster of yeasts and bacteria, a dash of which is essential for making every loaf of authentic sourdough bread.
These bakers will cancel a trip if no suitable starter-sitter can be found. Some give their starters names, and when they think no one is listening might even whisper words of encouragement.
Tracy Marks of Cakebread Artisan Bakery, in Courtenay on Vancouver Island, admits to talking to the starter all the time. "Our sour is called The Master of the Universe, and it really is a member of the bakery team and a tangible personality around the shop," she says.
Andrea Damon Gibson, baker and founder of Toronto-based Fred's Bread, explains this relationship.
"When you mix together flour and water at room temperature, cover and leave it for a day or so, it will begin to bubble. It's then that your lifelong responsibility begins," she says. "This baby has a regular feeding schedule; three times a day, every day, or else. It needs a constant temperature of about 24C, and it needs you."
Ms. Gibson made her first starter in her apartment, in December, 1994, and like any new mother made mistakes.
"We woke up Christmas morning, the kitchen floor covered with gooey, sour, bubbling batter that had escaped from the bins overnight because I had neglected to feed it before falling into bed on Christmas Eve. It took hours to scrape it off the floor."
Sounds like the plot of a cheesy seventies horror flick. But the life of a sourdough starter and its guardian can also read like a spy novel. Ms. Marks recounts how Cakebread acquired its starter. "It was born at the San Francisco Baking Institute - a hive of artisan-style bread enthusiasts - and we all tend and cajole it along with the greatest of care and respect."
It was smuggled across the border six years ago "with a bit of luck and skulduggery" - as Ms. Marks puts it - by Sherry Marshall-Bruce, Cakebread's late founder. Tucking a container of the smelly stuff into her luggage, Ms. Marshall-Bruce successfully slipped it past Canada Customs. That's the kind of thing one could get away with in those innocent pre-9/11 days.
While "the sour" is relatively young, at six years of age, Ms. Marks explains what makes it special.
"It contains unique and famous wild yeasts from San Francisco, arguably the epicentre of sourdough bread on the West Coast. The offspring of those tiny creatures, carefully nurtured in the moist Pacific Coast air, commingled with the ambient yeasts of the B.C. rain forest to form the backbone of the bread we bake."
Famous wild yeasts, eh? Guess you'd have to be a sourdough nerd to know that. But just as the yeasts that ferment the sugars in grapes and barley affect the flavour of wine and beer, so bread yeasts from different regions result in the loaf's personality, or terroir. And according to Ms. Marks, the strains that drift on the air around San Francisco Bay are renowned in the world of sourdough.
In the life of a starter, six years is a mere infant. Toronto-based chef Marc Thuet's levain is still bubbling away after 200 years in the family and one clandestine trip across the pond.
At Brick Street Bread in Toronto, baker Simon Silander's starter, at 35, has racked up a few air miles too. It's the offspring of a "mother" belonging to Clive Mellum, a fifth-generation British baker, who teaches craft bread-making.
This is what these folks do. Mentors share bits of their starters with favourite students, and families pass down these living heirlooms, sometimes through several generations.
But not all bakers are so sentimental.
Jean Marc Riant of Boulangerie La Vendéenne in Halifax is a practical sort and a believer in technology. Originally from La Vendée on the Atlantic coast of France, Mr. Riant has been baking with a starter he began in 1991, made from whole-wheat flour, water and a bit of honey.
"I don't have a special name for it, but I take special care of it. I don't want to have to start again. It takes too long."
And unlike some, Mr. Riant is not trapped at home, afraid to leave his precious levain in the clumsy hands of, well, anyone else.
"Not me. I go on vacation!" There's a hint of superiority and a little chuckle in his voice. "I have a machine, the patolevain."
So, it's technology - an incubator-babysitter - that keeps Mr. Riant and his levain from becoming co-dependant.
For many, the starter is a living link to the past. For Ms. Marks, it's also a memorial. "Sherry is gone, but the San Francisco sourdough starter she crafted is with us every day as a reminder of things transitory and perennial."
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