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  • Quartz Obsession — Sourdough — Card 1

    Sourdough is slow stuff—bread with a timeline that stretches over days, where you’re expected to be on hand to tend to its whims, prod it and fold it, and lay it gently to rest in a basket at seemingly random multi-hour intervals. In this modern world, who has the time? Enter lockdown. Sourdough is the undisputed king of Covid-19, and slow, quiet days that cry out for well-buttered bread.

    Sourdough has its detractors: Baking forums are full of sob stories about loaves the shape and consistency of a deflated American football. Meanwhile, experienced bakers have taken to kvetching about newbie enthusiasts laying claim to bags and bags of flour. Ignore them all. Sourdough isn’t as hard as it looks, providing you read carefully, follow the instructions, and don’t rush it. Your patience will be rewarded with delicious, Insta-friendly loaves. Let’s dig in.

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  • Quartz Obsession — Sourdough — Card 2

    2,600: Pages in Modernist Bread, a $500, five-volume meditation on all things bread

    304,000: Members of the subreddit r/breadit, where “everything must be related to bread (leavened cooked flour of any kind), especially made at home”

    $11.25: Cost of a sourdough country loaf at San Francisco’s iconic Tartine bakery

    $2.6 billion: Estimated value of the global sourdough market in 2018

    1,900: Approximate calories in an average loaf of whole wheat sourdough

    5 billion: Lactobacilli bacteria in every teaspoon of starter dough

    3.8 to 4.6: pH range of sourdough bread

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  • Quartz Obsession — Sourdough — Card 3

    Normally, you might beg some starter off a friend. To properly observe social distancing, you can make your own from a mixture of flour and water, “fed” with more flour and water daily over the course of about a week. Quartz reporter and resident sourdough expert Tim McDonnell describes the result as a “a naturally fermented goo that can replace yeast as a leavening agent in bread and requires only flour, water, and time.”

    Here’s the science behind it: “Flour naturally contains a mixture of wild yeast and bacteria. When mixed with water, starch in the flour is converted to the sugars glucose and maltose. Yeast love to eat those, and then emit carbon dioxide. As the carbon dioxide bubbles are captured by gluten protein strands in dough, they cause the mixture to rise…. Free-floating yeast and bacteria in the atmosphere in your kitchen can also join the party (the ‘sour’ tang comes from lactic acid bacteria).” Your sourdough starter is unique, telling a rich microbial story about your kitchen, pets, and environment.

    McDonnell’s own recipe uses a mixture of two flours and water, though the Kitchn’s version is simpler for those with limited access to grocers. Why bother? It just tastes better. “Using a starter to make bread takes longer than using yeast,” McDonnell writes, “but the result is well worth it: A more complex, tangy, nutty flavor, and a chewier texture.”

    Once your starter is well underway, here’s his well-tested recipe for a straight-forward boule.

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  • Quartz Obsession — Sourdough — Card 4

    To the uninitiated, a proliferation of intensely nerdy vocab can make it hard to know where to start. But it’s not so complicated. Here’s a shortlist to demystify the process:

    🍞Autolyse: The process of leaving a combination of flour and water to sit, allowing the flour to hydrate. (It saves you having to knead.)

    🍞Banneton: A basket, sometimes lined with linen, used to shape and hold the loaf while it proves.

    🍞Boule: A round loaf, from the French for “ball.”

    🍞Crumb: What the inside of the loaf looks like.

    🍞Hydration: The ratio of water and other liquid ingredients to flour in the dough.

    🍞Levain: Another term for a sourdough starter, though you sometimes see finished loaves referred to as levain, a shortened version of “pain au levain,” or “bread from levain.”

    🍞Score: To lightly cut into an uncut loaf, helping to create pretty patterns. Bakers often use a double-sided blade known as a lame for this.

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  • Quartz Obsession — Sourdough — Card 5

    Bittersweet strategies. Why do some medical crowdfunding campaigns succeed, and others fail? Some of the reasons are beyond people’s control. But there are key elements to money-making campaigns, and optimizing those is the work of a cottage industry of consultants.

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  • Quartz Obsession — Sourdough — Card 6

    “To ferment your own food is to lodge a small but eloquent protest—on behalf of the senses and the microbes—against the homogenization of flavors and food experiences now rolling like a great, undifferentiated lawn across the globe.”

    Journalist Michael Pollan, in Cooked

    “Sourdough bread is much overrated and is difficult to perfect at home.”

    Food writer and television personality James Beard

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  • Quartz Obsession — Sourdough — Card 8

    Until recently, Seamus Blackley’s main claim to fame was inventing the Xbox, one of the world’s most popular gaming consoles. Now he has another feather in his cap, having successfully recreated ancient Egyptian bread, using yeast cultivated from samples from four millennia ago and the traditional tools and techniques of the period.

    In a surprisingly thrilling Twitter thread, Blackley lays out the whos, wheres, and hows of the process. The bread itself was baked in a conical clay pot, cooked in a fire pit. But how did it taste? Amazing, he said, despite having scorched its top: “Light and fluffy and satisfying. Old Kingdom Egyptians were really smart, and really good bakers!”

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  • Quartz Obsession — Sourdough — Card 9

    12,400 BC: The oldest known bread is baked in what is now northeast Jordan.

    202 BC: Water-powered mills are used for the first time, in China, to turn grain into flour.

    1849: Isidore Boudin, a recent arrival from Burgundy, France, establishes San Francisco’s Boudin Bakery and the sourdough starter used to this day.

    1860: Microbiologist Louis Pasteur discovers the microbes that make yeast-powered fermentation work.

    1932: Pierre Poilâne opens his eponymous bakery on Paris’s Left Bank, specializing in sourdough boules.

    1943: The US Secretary of Agriculture bans sliced bread to conserve resources during WWII. Fleischmann’s begins to sell active dry yeast, developed for use in the war.

    2014: “Artisanal toast” is named the year’s greatest food trend, sparking an outsized backlash.

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  • Quartz Obsession — Sourdough — Card 10

    In the early 20th century, California Klondike gold miners were often known as “Sourdoughs” for their habit of carrying sourdough starter in their backpacks. The same term was used in Alaska for trappers and miners, who kept their starters warm by keeping them close to their bodies.

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  • Quartz Obsession — Sourdough — Card 11

    One of the more distressing elements of making sourdough is the discard—excess starter produced in the feeding process. You could make pancakes, crackers, or any number of “sourdough discard” recipes with the excess, but it’s a nuisance. Chucking the “discard,” meanwhile, feels wasteful.

    In a video tutorial, British sourdough master Bake with Jack has a solution, the “scrapings method.” Here’s the gist: You don’t need to feed your starter as much as you think you do.

    He feeds the starter once a week with only a little more flour and water than he’ll need for his weekly loaf. The rest of the time, he keeps the scrapings of the starter in his fridge, lying dormant until he needs it. “Pop the lid back on, pop it in the fridge for a week and do the same thing next week,” he says. “Nothing left over, nothing to throw away, just a dirty pot.”

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  • Quartz Obsession — Sourdough — Card 12

    You don’t need to be a baker to enjoy this deeply soothing collection of bread timelapse videos. Marvel as the dough inflates; goggle at the perfect scoring; catch yourself gasping aloud as the loaf’s ear burnishes to a rich gold. These videos are the work of Instagram user Jacob Rosendahl, aka @bread_by_rosendahl.

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  • Quartz Obsession — Sourdough — Card 13

    The curator of the Puratos Center for Bread Flavor, in St. Vith, Belgium, has living treasure on his hands: Bubbling away on the library’s refrigerated shelves sit more than 150 sourdough starters, sourced from every corner of the globe. Each is lovingly cared for, keeper Karl De Smedt told the New York Times: “A starter has its own heart, almost its own will,” he said. “Treat a starter nice and it will reward you tremendously, like a good friend.” Some are said to be more than 500 years old (though he cautions there’s no way of knowing for sure). The library is closed to visitors, but can be perused at a distance online.

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