Eating expired yogurt can be risky, but whether it is safe to eat yogurt that is 2 months past its expiration date depends on several factors. In some cases, yogurt that has been stored properly may still be consumable if it has only been expired for a short period of time. However, yogurt that is several months past its expiration should generally be discarded.
Yogurt that is 2 months past its printed expiration date could potentially still be safe to eat if it has been continually refrigerated and the seal remains unbroken. However, expired yogurt tends to taste sour and unpalatable due to bacteria growth, so it likely won’t be a pleasant experience. The risk of foodborne illness increases the longer yogurt sits past its expiration date. When in doubt, it’s best to discard yogurt 2 months after its expiration.
How to Tell if Expired Yogurt is Safe to Eat
Here are some tips for evaluating if yogurt is still safe to eat after its expiration date:
- Check the appearance – Unexpired yogurt should appear thick and creamy with no discoloration. Separation of whey or mold growth indicates spoilage.
- Smell the yogurt – Discard yogurt with an off or sour smell.
- Check the texture – Expired yogurt will become watery as whey separates. Toss yogurt with a slimy consistency.
- Taste a small amount – Sour, bitter, or funky flavors are a sign of spoilage.
- Ensure it was stored properly – Yogurt needs continuous refrigeration at 40°F or below.
- Look for signs of damage – Don’t eat yogurt from swollen, bloated, or leaking containers.
If the yogurt passes these checks and has only been expired for up to 2 months, it may be safe to eat if you’re willing to tolerate the weakened flavor and texture.
Why Yogurt Expires
Yogurt has a relatively short shelf life compared to many other dairy products. Fresh yogurt is perishable and has an optimal quality period of 1-2 weeks after the production date if stored properly in the refrigerator. There are two main reasons why yogurt goes bad quickly:
- Bacterial cultures – Yogurt is made by fermenting milk with live bacterial cultures like Lactobacillus bulgaricus and Streptococcus thermophilus. These cultures are sensitive to environmental changes and continue fermenting milk sugars during storage, causing yogurt to spoil faster.
- Water content – Yogurt has a high moisture content. Water promotes microbial growth and chemical reactions that can degrade nutrients, flavor, and texture.
Once opened, the bacterial cultures are exposed to more oxygen. Beneficial probiotics decline while contaminating microbes multiply, causing quicker spoilage.
Microbial Growth in Expired Yogurt
Bacteria and yeasts are the primary microbes responsible for yogurt spoilage. Here are some of the main offenders:
Lactic Acid Bacteria
As yogurt’s beneficial lactic acid bacteria like L. bulgaricus and S. thermophilus continue fermenting lactose, they produce lactic acid. Increased acidity gives expired yogurt its characteristically sour taste.
Yeasts like Candida, Saccharomyces, and Torulopsis are frequently found in spoiled yogurt. Yeasts ferment natural sugars into ethanol and carbon dioxide, resulting in yogurt that tastes alcoholic or fizzy.
Common yogurt molds include Mucor, Rhizopus, and Penicillium species. They grow filamentous hyphae that appear fuzzy or powdery on the surface. Mold growth may indicate severe spoilage.
Bacteria like Escherichia coli, Enterobacter, and Klebsiella produce gas from lactose breakdown that blows up yogurt packaging. These gas-producing coliforms are usually harmless, but indicate expired yogurt.
Dangerous bacteria like Staphylococcus aureus, Salmonella, and Listeria can rarely grow if yogurt is grossly mishandled. Proper refrigeration minimizes pathogenic growth. However, these bacteria may start multiplying once yogurt is expired.
Changes in Expired Yogurt
As yogurt ages past its expiration date, you can expect the following changes:
Expired yogurt becomes much more liquid as the structure breaks down. The thick, creamy texture is lost as whey separates. Syneresis or watery pockets appear due to proteins losing solubility.
The pH drops as lactic acid bacteria continue to convert lactose into lactic acid. Yogurt typically has a pH around 4.0-4.5 when fresh, but spoiled yogurt may drop below 4.0.
The yogurt separates into clumpy curds surrounded by yellowish whey. This whey contains water, lactose, proteins, and minerals.
Sour, yeasty, or unclean flavors develop as spoilage microbes grow. Rancid flavors may occur from lipid oxidation. The fruity, tangy taste is replaced by harsh acidity.
Gas-producing bacteria form carbon dioxide bubbles that blow up the yogurt packaging. The CO2 produces a fizzy, alcoholic taste.
Fuzzy spots or filamentous strands of mold appear on the yogurt’s surface, often in green, black, or white colors. Mold occurs from exposure to oxygen.
How Long Does Yogurt Last When Unopened?
The shelf life of yogurt depends on the production and expiration date printed on the package. Here are some general yogurt expiration guidelines for unopened containers:
|Type of Yogurt
|Refrigerator Shelf Life
|1-2 weeks past sell-by date
|Up to 1 month past expiration
|Yogurt with fruit
|7-10 days past expiration
|10-14 days when unopened
|14 days refrigerated
Note that expiration dates are not always exact – they provide an estimate of when the manufacturer can still guarantee peak quality and safety. Unopened yogurt may still be usable for a short period beyond its sell-by date if it has been continuously refrigerated.
How Long Does Opened Yogurt Last?
Once opened, the shelf life of yogurt becomes much shorter. This is because exposing yogurt to air introduces contaminating yeasts and molds. Follow these yogurt storage guidelines after opening:
- Use within 7-10 days of opening.
- Yogurt parfaits last 3-5 days.
- Pureed fruit yogurt lasts 5-7 days.
- Greek yogurt keeps slightly longer, around 7-14 days.
Discard any yogurt that smells bad, looks moldy, or separates after opening. Don’t rely on the original expiration date once exposed to air.
Proper Yogurt Storage
To get the most shelf life out of yogurt after purchasing, be sure to store it properly:
- Refrigerate below 40°F – Cold temperatures slow yeast, mold, and bacteria growth.
- Avoid temperature fluctuations – Frequent warming ups and cool downs accelerate spoilage.
- Store in original container – This prevents contamination and leakage.
- Check seal integrity – Don’t use yogurt with a broken seal.
- Monitor expiration dates – Use oldest yogurt first.
- Keep away from light – Light degrades vitamins and flavors.
- Avoid freezing – Freezing separates whey and ruins texture.
Make sure your fridge temperature is adjusted properly and consistently around 40°F. The colder the storage, the longer yogurt stays fresh.
Can You Freeze Yogurt?
Freezing isn’t recommended for storing yogurt. The ice crystals that form damage the cell structure, causing an irreversible breakdown of the thick texture. Thawed yogurt becomes very runny as fluids separate from the solid curds.
However, frozen yogurt designed for freezing maintains its smooth, scoopable texture. This is because commercial frozen yogurt contains stabilizers like gelatin, guar gum, or carrageenan. So avoid freezing conventional yogurt, but frozen yogurt is fine.
What Happens If You Eat Bad Yogurt?
Eating expired, spoiled yogurt is not necessarily dangerous if it’s been refrigerated properly throughout its shelf life. However, yogurt that’s weeks or months past its prime carries some health risks:
- Foodborne illness – Outgrown bacteria like E. coli O157:H7 or Salmonella may cause nausea, vomiting, diarrhea, and fever if enough are ingested. Risk increases the longer yogurt is expired.
- Unpleasant symptoms – Stomach pain, indigestion, nausea, and vomiting can occur from eating very sour or moldy yogurt.
- Food intolerance – People with dairy sensitivities may experience bloating, gas, cramps, and diarrhea from excess lactic acid and galactose in spoiled yogurt.
If yogurt looks or smells questionable, err on the side of caution and throw it away. The potential stomach upset isn’t worth the risk of eating gross expired yogurt.
How To Use Up Yogurt Before It Expires
To avoid wasting half-used containers or yogurt that’s close to expiration, try these creative ways to use up yogurt before it spoils:
- Make yogurt parfaits with granola and fruit.
- Blend into smoothies with frozen fruit and juice.
- Swirl into oatmeal along with honey, cinnamon, or maple syrup.
- Use as a substitute for milk or mayo in dips and dressings.
- Make yogurt popsicles by mixing in fruit puree.
- Substitute for sour cream on top of baked potatoes.
- Whip up homemade yogurt ranch dressing.
- Freeze individual portions to use later in recipes.
- Make yogurt bark by mixing in fruit, spreading on a pan, and freezing.
Yogurt also works great in many baked goods like quick breads, muffins, and cakes. Get creative with ways to use up yogurt so it doesn’t end up in the trash.
The Bottom Line
Yogurt that is only a week or two past expiration can sometimes still be safe if it meets all the right quality checks. However, eating yogurt more than 2 months expired is generally not recommended. At that point, the probability of spoilage and foodborne illness is too high. Discard severely outdated yogurt and find a fresh container for the best flavor, texture, and safety.