How Long Can You Leave Butter Out?
If you didn't grow up in a "counter butter" household, the idea may seem counterintuitive. We don't store milk or sour cream outside of the refrigerator because it spoils. So what's that all about?
Can You Keep Butter on the Counter?
Yes, butter can be left out on the counter for hours or even days. It's pretty unique among dairy products that way.
Just because you can doesn't mean you should, however. At the least, there are some rules you should follow to keep room-temperature butter fresh and safe to consume. More on this in a moment.
Why Can You Leave Butter Out, But Not Other Dairy?
Most dairy products have a balance of proteins, carbohydrates, and fats that make them excellent food – not just for us, but for bacteria and fungi. Some of these microorganisms "spoil" the product by making it unpleasant to eat, while others make the food outright dangerous by causing foodborne illness.
Since bacteria multiply so quickly in most dairy products, they're considered Time and Temperature Control for Safety (TCS) foods. Basically, this means that to keep the food safe to eat, you need to control how long it spends at certain temperatures. Room temperature is usually the best environment for microbes to breed. Keeping dairy in the fridge slows this process down.
To be extra safe, most dairy is pasteurized to kill harmful microbes.
Butter is special because it's not as tasty to bacteria and fungi as other dairy. To qualify as butter according to U.S. guidelines, a dairy product has to be at least 80% fat. Microbes don't like high-fat foods. They prefer proteins and carbohydrates, and the process of making butter strips those out. Salted butter is even less hospitable to microbes because salt inhibits bacterial growth.
The USDA considers all butter sold commercially in the U.S. to be safe at room temperature, partly because the FDA has banned the sale of raw (unpasteurized) dairy.
If you buy homemade, raw, or unpasteurized butter, it will spoil much faster on the counter and may make you sick.
Can You Leave Margerine Out On the Counter?
It doesn't matter if you can't believe it's not butter – margarine is made of different stuff. Like butter, it's high in fat and low in ideal microbe food. That makes it safe to leave out on the counter, but not wise.
At room temperature, margarine (especially the soft kind, in a tub) will change shape, texture, and flavor. If left out long enough, it can turn liquid and go rancid overnight. Stick margarine (also called hard margarine) can last a little longer than soft margarine, but for margarine to taste good, it needs to be kept in the fridge.
How Long Can Butter Sit Out?
This is a little complicated – it depends on the kind of butter, the temperature of the room, and the container you use.
We already explained why the type of butter matters – pasteurized and salted butter has less microbial activity than raw and unsalted butter.
The container matters because exposure to light and air will shorten butter's shelf-life. Remove the wax paper from the butter stick and use either a butter dish or a butter crock/bell. Butter dishes and butter bells both reduce exposure to air and light, but butter crocks or bells do so by submerging the butter in water. Butter dishes are just a dry, closed space.
Temperature is a big one, though, because outside of the refrigerator, it can vary a lot.
How Long Does Butter Last at Room Temperature?
"Room temperature" is generally between 68 and 77°F. That's a reasonable range for people, but a significant gap for microbial growth.
If your kitchen or pantry is 65°F, salted butter can last for weeks in the right container, but at 80°F, you'll only get a couple days. If your home is on the warmer end, you may want to limit the amount of butter stored at room temperature (or simply keep all your butter in the fridge).
The best way to know how long butter will stay good on your counter is to look it over before each use. Pay attention to its appearance, texture, odor, and flavor. Rancid butter can't actually make you sick, so it's really subjective. It's a matter of how long it stays edible by your standards.
How Long Does Butter Last in the Fridge? In the Freezer?
Butter can safely last three to six months in the fridge. In the freezer, butter can remain "safe" indefinitely. However, its quality will degrade eventually. It's best to use frozen stick butter within 8-12 months.
The exact length of time in all cases depends (again) on temperature and storage methods. It also depends on your sensitivity to taste and texture – since butter absorbs the odors and flavors around it, it can become unusable long before it spoils.
It's best to store stick butter wrapped in foil, parchment paper, or cling wrap. Wax paper degrades the butter's flavor and quality, so avoid it. For longer-lasting quality, replace the wrapping with foil or parchment paper.
Ideally, you want to package butter in a way that minimizes air and light exposure, as well as excess moisture (to prevent freezer burn). You also want to store butter away from anything with a strong odor.
Butter stored in the door of your refrigerator or freezer will go bad faster because it will be warmer (or at least, more variable in temperature). To get the most out of butter, store it at the back of the compartment, where the temperature is the lowest and most consistent.
Learn More About Food Safety
Food safety is a complicated subject. It's one thing if only your stomach is on the line, but food service professionals need training and practice to manage food safety consistently. Check out our ANAB-accredited, state-approved online courses to learn more about safe food handling and food safety management.