​How to Tell If Greek Yogurt Is Bad?

Storage conditions change its lifespan. Being opened or unopened matters. Homemade yogurt spoils faster than store-bought. Leaving yogurt out too long speeds up spoilage. Poor sealing helps mold and bacteria grow.

How Long Is the Shelf Life of Greek Yogurt?

Homemade Greek Yogurt
Homemade yogurt has a short life. It uses fresh milk and cultures. It lacks commercial preservatives. Keep it in a sealed container in the fridge. It lasts three to five days.
Use clean spoons to serve it. This prevents germs. If you see texture, smell, or color changes, throw it away. You can freeze it. But thawed yogurt may be watery. Use it in smoothies after thawing.
Commercially Purchased Greek Yogurt
Store-bought yogurt lasts longer. Factories use special processes. Machines like Yogurt Filling Machine pack it cleanly. This prevents germs. An unopened container lasts two to four weeks past the "sell-by" date. Keep it cold in the fridge.
The "sell-by" date is for stores. The "best-by" date is for top quality. Yogurt is often safe after this date if it looks fine. Once opened, it spoils faster.

First, look for mold. Mold can be fuzzy and white, green, blue, or black. Throw it all away if you see mold. Also, look for odd colors. Good yogurt is white or cream-colored. Yellow or gray means it is bad.

Next, smell it. Fresh yogurt smells tangy. Bad yogurt smells very sour, rotten, or yeasty. If it smells wrong, do not eat it. Then, feel the texture. Good yogurt is thick and smooth. Bad yogurt is runny, lumpy, or slimy. A little liquid on top is normal. You can mix it in. But a lot of liquid or slime means it is spoiled.

Last, taste a tiny bit if other signs are good. Bad yogurt tastes very sour or bitter. Spit it out if it tastes wrong.

How Long Does Greek Yogurt Last After Opening?

Opened yogurt spoils quickly. Air and germs get inside.  It lasts five to ten days in the fridge.
Keep the lid shut tight. Use a clean spoon every time. Put the yogurt back in the fridge right away. Do not leave it out for over two hours.
You can freeze opened yogurt. It lasts two months frozen. Thaw it in the fridge. It will be watery. Use it for smoothies or baking.

Usually, do not eat expired yogurt. This is especially true if stored wrong. The date is a quality guide. Safety is key. Bacteria can grow without visible signs.
It might be safe if it is only a few days past the "best-by" date. It must be cold and look normal. But be careful. Sick, pregnant, or elderly people should not risk it. They get sick more easily.
Remember, the "sell-by" date is not an expiration date. Yogurt is often safe after that date. But always check it first.

What Happens If You Eat Expired Greek Yogurt?

Eating bad yogurt can make you sick. You may feel nauseous. You might vomit or have diarrhea. You could get stomach cramps or a fever. These signs start hours or days later.
Most times, the illness is mild. It ends in a day or two. Drink lots of water. Have broth or electrolyte drinks. Avoid dairy, spicy foods, and caffeine until you feel better.
See a doctor if symptoms are severe. Get help for constant vomiting, bloody stool, a high fever, or dehydration. This is vital for children, the elderly, and people with health problems.