The Science of Yogurt 

And the hardworking bacteria who produce it.

Published Apr. 22, 2022.

Yogurt is an incredibly important staple in cultures across the globe—while its exact origins are a little bit fuzzy, historians believe it was discovered by happy accident sometime around 5000 BC in Mesopotamia, when fresh milk was exposed to wild bacteria. The results tasted great, were more shelf stable than fresh milk, and could be used in countless ways, so it’s no wonder that the product gained a worldwide following. 

These days, there are tons of options for buying yogurt at the supermarket—but for the best-ever yogurt, try your hand at homemade. When you make your own yogurt, you’re in full control of the end result, so you can dial in your yogurt to your ideal levels of creaminess and tartness, or even add extra flavors. All you need is a little scientific know-how.

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How Liquid Milk Turns into Creamy Yogurt

1. Milk is heated to pasteurize it. This improves the milk protein’s ability to set into a creamy texture, and it kills off any wild bacteria that could negatively impact fermentation.

2. Live bacteria are added to the mix and left to do their work in a process known as culturing. They’re pretty picky about temperature, so the yogurt needs to be held at about 110-115 F.

3. As the milk becomes more acidic, the milk proteins form a network that traps water and forms a soft gel.

What does this process look like in your kitchen? Watch the full episode of What’s Eating Dan? below to find out. 

Homemade Yogurt

DIY yogurt has an incomparably fresh, milky taste—and it's entirely customizable. Whether you like it mild or tart, creamy or lean, our foolproof method has you covered.
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Tanabour (Armenian Yogurt and Barley Soup)

Yogurt brings milky tang—and an exceptional satiny texture—to the soothing Armenian soup known as tanabour.
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Frozen Yogurt

In most homemade fro yo, tangy taste and a creamy, smooth texture are mutually exclusive. We wanted both qualities in the same scoop.
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