How long does yogurt last once opened in the fridge?

According to the USDA, refrigerated yogurt is typically best consumed within one to two weeks of purchase. The shelf life, however, can shorten significantly after the container has been opened, depending on proper storage and the type of yogurt. Knowing the signs of spoilage and correct handling procedures is crucial to ensure food safety.

Quick Summary

Once opened, yogurt should generally be consumed within 7 to 10 days, but this timeframe can vary based on storage and yogurt type. Proper storage involves keeping it in the coldest part of the fridge and using clean utensils. Key indicators of spoilage include mold, a bad smell, or excessive liquid, requiring immediate disposal.

Key Points

• Shelf Life Varies: Once opened, consume most yogurts within 7-10 days, though Greek yogurt can last longer.

• Check for Spoilage: Look for mold, excessive liquid, or a change in texture and smell before eating.

• Proper Storage is Key: Store yogurt in the coldest part of the fridge and keep the container tightly sealed.

• Avoid Contamination: Always use a clean spoon and avoid double-dipping to prevent introducing bacteria.

• Freezing is an Option: Unfinished yogurt can be frozen for up to two months, though the texture may change upon thawing.

General Shelf Life of Opened Yogurt

Once you break the seal on a container of yogurt, its protective barrier is gone, making it susceptible to bacteria and other contaminants. While an unopened tub can last for weeks past its sell-by date, the clock on an opened container is much shorter. For optimal quality and safety, most opened yogurts are best enjoyed within 7 to 10 days. This guideline applies to most store-bought varieties, though specific factors like yogurt type and storage practices can influence this timeframe.

Factors That Affect Yogurt's Freshness

Several variables determine how long your opened yogurt will remain fresh and safe to eat. Paying attention to these can help you maximize its longevity and minimize waste.

• Storage Temperature: Yogurt must be kept at a consistent temperature of 40°F (4°C) or below. The back of the refrigerator is typically the coldest and most stable area, while the door often fluctuates in temperature and should be avoided for dairy products.
• Cross-Contamination: A major cause of premature spoilage is introducing foreign bacteria. Always use a clean spoon each time you scoop out yogurt. Double-dipping or using a utensil that has touched other food can accelerate spoilage.
• Container Sealing: Ensure the container is tightly sealed after every use to minimize air exposure. Exposure to air promotes mold and bacterial growth, shortening the shelf life significantly.
• Added Ingredients: Flavored yogurts, especially those with added fruit or sugar, may spoil faster than plain yogurt. The sugars can provide a food source for spoilage-causing bacteria and yeast. Plain yogurt's natural acidity acts as a preservative, offering a bit more resistance.
• Ingredient Quality: The initial freshness and quality of the yogurt upon opening also play a role. If a yogurt is already close to its sell-by date when opened, its remaining shelf life will be shorter.

Spotting the Signs of Spoiled Yogurt

While a sell-by date offers a guideline for peak quality, your senses are the most reliable tool for checking if yogurt has gone bad. If you notice any of these signs, it's best to discard the yogurt to avoid foodborne illness.

• Mold Growth: Any visible mold, regardless of color (green, blue, gray, or white), is a clear sign of spoilage. Do not simply scrape off the mold, as the microscopic roots have likely contaminated the entire container.
• Excessive Liquid: A small layer of whey separation on top of fresh yogurt is normal. However, if there's a large amount of liquid, or if the yogurt is watery or curdled even after stirring, it's an indicator of age and potential spoilage.
• Bad Odor: A fresh, plain yogurt has a mild, tangy scent. If you detect a rancid, sour, or musty smell, it's a sign that the product has spoiled and should be thrown out.
• Texture Change: Spoiled yogurt will often have a lumpy, grainy, or excessively thick texture that is no longer smooth and creamy. A bloated container is also a sign of fermentation and bacterial activity.
• Off Taste: If you decide to do a small taste test and the flavor is unusually sour, bitter, or stale, discard the yogurt immediately without swallowing.

Comparison of Different Yogurt Types

Not all yogurts are created equal when it comes to shelf life. The processing and consistency of different types can impact how long they stay fresh after opening. This table provides a helpful comparison for reference.

Yogurt Type	Typical Shelf Life Once Opened	Why it's different	Considerations
Regular Yogurt	7 to 10 days	Standard water content and texture.	Subject to general spoilage rules; watch for whey separation.
Greek or Icelandic Yogurt	10 to 14 days or longer	Strained, thicker consistency with less whey and water content. The straining process often increases acidity.	Still needs proper storage; dense texture can hide early signs of spoilage.
Flavored Yogurt	5 to 7 days, or shorter	Added sugars and fruit can accelerate yeast and mold growth.	Always check the consistency and smell carefully before consuming.
Homemade Yogurt	Around 7 to 10 days	Contains live cultures but lacks the stabilizers and pasteurization processes of commercial products.	Monitor closely for any changes in smell or appearance; follow best storage practices diligently.
Plant-Based Yogurt	Varies by brand	Ingredients like coconut, almond, or soy can have different spoilage rates.	Check the manufacturer's specific instructions on the packaging for shelf life.

Best Practices for Optimal Yogurt Storage

To extend the life of your opened yogurt and maintain its quality, follow these key practices:

• Refrigerate Immediately: Return the yogurt to the fridge as soon as you've used it. Never leave it out at room temperature for more than two hours.
• Keep it Airtight: After serving, smooth the surface of the remaining yogurt and press plastic wrap directly against it before sealing the lid. This minimizes air contact and helps prevent mold.
• Store in the Right Spot: Place the yogurt in the back of the fridge, away from the door, where the temperature is most consistent.
• Use Clean Utensils: Only use fresh, clean utensils to prevent introducing bacteria from your mouth or other foods.
• Freeze if Needed: If you know you won't finish a large tub, yogurt can be frozen for up to two months, though the texture may change upon thawing. It's still suitable for baking or smoothies after being thawed safely in the refrigerator.

Conclusion

For optimal safety and flavor, an opened container of yogurt should be consumed within 7 to 10 days, with variations depending on the type and how it is stored. Paying close attention to visual cues like mold, excessive liquid, and changes in texture, as well as any off smells, is the most reliable way to determine freshness. Following simple best practices, such as immediate refrigeration and using clean utensils, can help extend your yogurt's life and ensure a safe and pleasant eating experience. When in doubt, it's always safest to throw it out rather than risk foodborne illness.

USDA's Food Safety and Inspection Service Foodkeeper app provides additional resources for food storage guidelines.

Frequently Asked Questions

Can you eat yogurt that has been open for longer than two weeks?

Eating yogurt that has been open for longer than two weeks is not recommended, as it significantly increases the risk of foodborne illness, especially if not stored under perfect conditions. Always check for signs of spoilage before consuming.

What does spoiled yogurt smell like?

Spoiled yogurt will have a distinctly off, rancid, or musty smell that is different from its usual mild, tangy aroma. When in doubt, trust your nose and throw it out.

Is the liquid on top of yogurt a sign of spoilage?

A small amount of liquid (whey) on top of yogurt is normal and can be stirred back in. However, an excessive amount of liquid that doesn't mix back in, or a watery consistency throughout, is a sign of spoilage.

Does freezing yogurt kill the probiotics?

Freezing does not kill probiotics, but it can alter the texture of the yogurt upon thawing. The thawed yogurt can still be used in recipes like smoothies or baking where a creamy consistency isn't essential.

Is it safe to eat yogurt past its 'best by' date if it's still unopened?

Yes, an unopened yogurt can often be safe to eat past its 'best by' date, which refers to peak quality, not safety. However, once opened, the recommended 7-10 day rule applies.

Can I just scrape off the mold from my yogurt and eat the rest?

No, if you see any mold on your yogurt, you should discard the entire container. Mold has microscopic roots that spread throughout the food, even if it's only visible on the surface.

How long can yogurt be left out at room temperature?

Yogurt should not be left out at room temperature for more than two hours. If left out longer, it enters the 'Danger Zone' where bacteria can multiply rapidly, and it should be discarded.