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The Science of Yogurt 

And the hardworking bacteria who produce it.
By 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. 

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JC
JOHN C.
16 days

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too. I've done this using a rimmed sheet pan instead of a skillet and put veggies and potatoes around the chicken for a one-pan meal. Broccoli gets nicely browned and yummy!

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too.

MD
MILES D.
JOHN C.
9 days

Amazed this recipe works out as well as it does. Would not have thought that the amount of time under the broiler would have produced a very juicy and favorable chicken with a very crispy crust. Used my 12" Lodge Cast Iron skillet (which can withstand 1000 degree temps to respond to those who wondered if it would work) and it turned out great. A "make again" as my family rates things. This is a great recipe, and I will definitely make it again. My butcher gladly butterflied the chicken for me, therefore I found it to be a fast and easy prep. I used my cast iron skillet- marvellous!

CM
CHARLES M.
11 days

John, wasn't it just amazing chicken? So much better than your typical oven baked chicken and on par if not better than gas or even charcoal grilled. It gets that smokey charcoal tasted and overnight koshering definitely helps, something I do when time permits. First-time I've pierced a whole chicken minus the times I make jerk chicken on the grill. Yup, the cast iron was not an issue.