How to Tell If Yogurt Is Bad

Nutritious, delicious and versatile, yogurt is a staple in many people's kitchens. When your favorite yogurt goes on sale, you may be tempted to buy a couple of extra tubs to have on hand. But how long does it last? Can you still eat yogurt past the "use by" date on the carton? Read on to discover how to safely store yogurt both before and after you open it and the signs that indicate your yogurt might have gone bad.

How to Properly Store Yogurt

All types of refrigerator-stable yogurt—that is, yogurt you find in the refrigerated section of the grocery store—should be stored in the refrigerator and consumed within one to two weeks from the date of purchase, according to the USDA FoodKeeper app. Keep yogurt fresh by storing it in the coldest part of the fridge where the temperature is the most consistent. So, push yogurt to the back of a shelf, and don't store it in the fridge door, where temperature fluctuations can accelerate spoilage.

Your fridge's temperature is also important—it should be set at 40°F or below to delay spoilage and the growth of disease-causing bacteria that may lead to food poisoning.

How Long Does Yogurt Last in the Fridge Once Opened?

While yogurt should be eaten within the USDA's suggested time frame of one to two weeks, spoilage can occur in a matter of days if open containers of yogurt are not properly handled. Here are two factors that can come into play that could affect the shelf life of your opened yogurt container.

Staying out at room temperature for too long

Once the yogurt container is opened, make sure it doesn't stay at room temperature for longer than two hours or longer than one hour if it's 90°F or hotter—once the temperature is above 40°F your yogurt is in the "danger zone" and is prone to spoilage.

Simply exposing yogurt to open air also increases the growth of bacteria and the spoilage rate, and an open container of yogurt is also more likely to absorb odors from other food items in the fridge. So as soon as you've scooped out your serving of yogurt, put the lid back on and put the yogurt back in the coldest part of the refrigerator.

Using dirty utensils

Got a large tub of yogurt and can't finish it all? Instead of eating out of the container and storing the rest in the fridge, use a clean spoon to scoop out the needed portion. Doing so reduces the risk of cross-contamination, and the yogurt can last longer.

What to Know About Your Yogurt's Expiration Date

When purchasing yogurt, always look at the "use by," "sell by" or "best buy" date printed on the yogurt. Here's a breakdown of what those expiration dates mean:

• "Sell-by" dates are aimed more at the retailer than the consumer, letting them know when a product should be off the shelves. Your yogurt should still be good for several days after this date.
• "Best if used by/best before" dates are an indicator of quality. The yogurt might not taste as good after this date or the texture might suffer, but it should not be bad or make you sick if you consume it after this date.
• "Use-by" dates indicate the last day the manufacturer recommends using the product based on quality, not safety. (The exception to this is infant formula, which should not be used after use-by dates.)

Yogurt should also have a note on the label about how long it can be stored in the fridge once opened. The dates themselves don't mean the product will be spoiled by a certain date, nor do they guarantee that the product will be at its peak quality at this date.

That said, it is best to follow the recommendations provided by the USDA—use yogurt within one to two weeks after the date of purchase. And if you notice signs of spoilage, the "use by" date and the recommendation no longer matters—throw it out.

How to Tell If Yogurt Has Gone Bad

When handling perishable foods like yogurt, it is crucial to trust your senses to find out whether the yogurt is still edible and safe to eat. Here are some signs to look out for.

Appearance

If you notice that the yogurt container is bloated before you open it, this is a sign of fermentation and spoilage—toss it or return it to the store for a refund. (The exception is if you are at a high altitude, when all sorts of containers can bulge from differences in air pressure inside and outside the container.)

When you first open refrigerated yogurt, you may notice a layer of watery-looking liquid on the surface. This fluid is whey, which you should not be concerned about—simply stir it back into the yogurt. However, if you see a change in the yogurt texture, such as an unusually large amount of liquid or liquid that's still visible after stirring, you should throw it out.

You should also ditch yogurt that has any noticeable mold. Scraping or scooping mold out doesn't help, as once there is any mold the entire container is contaminated.

Smell

Unless it's flavored, fresh yogurt should have a neutral scent. If you note any rancid, sour or off odors, it is time to toss it out.

Taste

Hopefully, the tips above give you enough information to spot a spoiled yogurt, but if you want to be extra sure, you can taste a small spoonful to see if the yogurt is still good. Spoiled yogurt may taste stale or exceptionally sour—your instincts will tell you the flavor is off. Avoid swallowing it and throw out the entire container.

What Happens If You Eat Spoiled Yogurt?

Despite following all the safe food handling and storage steps, it's still possible to eat spoiled yogurt since there are disease-causing bacteria that are invisible to the naked eye. Young children, people over 65 years old and those with a weakened immune system, such as pregnant individuals and those living with a chronic disease, also are more prone to getting sick from food poisoning. If you feel ill and experience symptoms such as nausea, diarrhea, vomiting, cramps, chills and headache, you should seek medical help.

Can You Freeze Yogurt?

Planning to stock up on yogurt? You can freeze yogurt for up to two months from when you bought it (it will technically still be safe after that but the flavors might suffer).

You can freeze yogurt in the original container or divide it into portions in separate airtight containers. Or pour or spoon the yogurt into an ice cube tray and then transfer the cubes to a food-grade sealable bag once they're frozen.

When ready to use the yogurt, you can use it frozen—for example, toss a cube or two into the blender with some fruit for a smoothie—or thaw it in the fridge and use it within one week.

It's worth noting that previously frozen yogurt might have a grainy texture. To reduce the grittiness, stir the thawed yogurt thoroughly or whirl it in a blender or food processor for a smoother consistency.

If the texture of previously frozen yogurt bothers you but you want to avoid food waste, consider adding it as the base of your favorite smoothie or smoothie bowls. Another option is using yogurt in baked goods such as muffins, quick bread and cakes.

How to Use Up Yogurt Before It Goes Bad

If you have yogurt sitting in the fridge close to the end of its shelf life and you don't feel like eating yet another bowl of yogurt, there are other ways to incorporate this nutritious food into your meals and snacks. You can use it to make tasty sweet treats like our Granola & Yogurt Breakfast Popsicles or Strawberry-Chocolate Greek Yogurt Bark. Yogurt also complements savory dishes like Chicken Shawarma, Sole Cakes and Red Lentil Fritters with Ginger-Yogurt Sauce. It's also a wonderful base for marinades, salad dressings, sauces and dips.

Bottom Line

Yogurt is a smooth and creamy dairy product that can be enjoyed alone or added to a variety of recipes. With a relatively short shelf life of one to two weeks in the refrigerator once opened, yogurt is best consumed as soon as possible. While you can also freeze yogurt for future use, yogurt can spoil anytime, even before it technically expires. Always trust your gut by using your senses to determine if it is edible. When in doubt, discard the yogurt to avoid unnecessary and unpleasant food poisoning symptoms.