Adding Dairy To Your Instant Pot Could Be A Recipe For Failure. Here's Why - Tasting Table

"The Instant Pot is great for making quick work of tough cuts of meat ( transform steak into a flavorful London broil, perhaps?), soups, or stews that would have otherwise taken hours of slow and steady simmering. However, if you've ever tried to make a creamy sauce or a cheesy soup in an Instant Pot, you may have encountered some textural trouble. Dairy and high-pressure cooking just do not mix well. Without the right touch, the hope of a velvety chowder or a decadent mac and cheese can quickly turn into a pot of split, grainy disappointment."

"Dairy is finicky under both heat and pressure. When cooking with milk, cream, or cheese on the stove, you can add it slowly or monitor the temperature and make gentle adjustments. In an Instant Pot, though, heat builds quickly and can climb much higher than what you would use on the stove. This rapid, uncontrolled heating causes milk proteins to seize up and separate from the fat and liquid. The result is a sauce or soup that can curdle and clump. If you're aiming for smooth, creamy results, it's essential to understand why this happens and know how to avoid it. The simplest solution is to wait until the very end of cooking to stir in your dairy. That way, you get the convenience of the Instant Pot without sacrificing texture or flavor."

"Dairy products are delicate due to the structure of their proteins and fats. Milk contains casein and whey proteins suspended in liquid, along with milk fat globules. When you heat milk or cream slowly on the stove, these proteins stay stable, and the mixture remains smooth. But in the high-pressure, high-temperature environment of an Instant Pot, those proteins denature rapidly. They bind to each other, squeeze out liquid, and form visible curds."

The Instant Pot excels at quickly cooking tough cuts of meat, soups, and stews that normally require long simmering. Dairy ingredients often separate under high-pressure cooking because heat builds rapidly and denatures milk proteins, causing them to bind, squeeze out liquid, and form curds. Acidic ingredients can worsen separation. Creamy sauces and cheesy soups risk becoming grainy or curdled if dairy is exposed to prolonged, uncontrolled heat and pressure. The simplest and most reliable technique to preserve a smooth texture is to add milk, cream, or cheese at the very end of the cooking cycle.

Read at Tasting Table