Everything You Ever Wanted to Know About Butter

Butter! It’s one of those things that makes things delicious. But what do we really know about the stuff? Let’s spread our butter knowledge with this butter FAQ.

What is butter?

Butter is basically the churned fat and protein component of cream—cream is, of course, the highest fat layer of milk. Take cream, agitate it in some way, and you basically have butter. 

Is butter dairy?

Yes, butter is absolutely a dairy product. Most butter you buy in the store is made from cow’s milk, though technically it can be made from any kind of milk. 

Does butter have lactose?

Butter is not 100% lactose-free, but it’s about as close as you can get—there are only .1 grams of lactose in an entire cup of butter. For this reason, many people who are lactose intolerant are still perfectly fine eating butter, though individual results may vary.

What is butter made of?

Butter is made of cream, which is the fattiest part of the milk. The cream is churned and salt is added, if it’s salted butter.

How is butter made?

If you’ve ever been to a living museum like Colonial Williamsburg, you may have seen a butter churn. This is how butter was made in the old days: You agitate the cream like this until the milk fat begins clumping together, making buttermilk. After churning, the grains of yellow fat are removed and blended together to make butter. You can accomplish the same thing with some cream, a Mason jar, and a lot of shaking. 

Today, the same basic process is used, though often at an industrial scale. The people at Grand Fermage have an interesting, illustrated step-by-step breakdown of how they make their product. It includes separating the cream from the milk, pasteurizing the cream, leaving the cream to cool and “mature” for 24 hours, churning, washing the butter grains, blending them together, and packaging the butter. 

Does butter go bad?

Yes, butter can go bad. While it can eventually grow mold, the earlier warning sign is a rancid smell. If your butter smells bad, it’s time to toss it. 

How long does butter last?

When kept in the fridge, butter will last for about two to three months. Out of the fridge, it will last for significantly less time, so best to keep it cool.

Can you freeze butter?

Of course, you literally can freeze butter—it will fit in the freezer and everything—but should you? The answer is, yes. You can keep butter in the freezer for up to four months. After that, it might start to pick up other flavors, which sounds gross.

Does butter have gluten?

Butter is a gluten-free food stuff, meaning it should be fine if you’re trying to cut gluten out of your diet. The only possible exception would be butter with added flavorings, which could conceivably contain gluten, so be sure to check the nutritional information on the label. 

What is sweet cream butter?

Don’t let the fancy name fool you; sweet cream butter is just another name for the typical butter you’d find on the grocery store shelf. It is made with cream and, typically, salt, although unsalted varieties are also available. 

What is cultivated butter?

With cultivated butter, bacterial cultures (similar to those used to make cheese and yogurt) are added to the cream before churning. These cultures ferment, giving the butter a creamier texture and a tangier flavor. 

What is Irish butter? 

Irish butter is just like normal butter but with a higher butterfat content—specifically 82%—so it’s super spreadable and extremely creamy. It also has a distinctive yellow hue, thanks to the carotene levels in the milk, which are due to Irish cows’ diets of carotene-rich grass. And, of course, Irish butter is from Ireland.