There’s a lot to choose when it comes to yogurt: Traditional, Greek, Kefir, Australian, Viking, non-dairy, lactose-free, low-fat and no-fat, bio-yogurt, and frozen yogurt. These are common kinds of yogurt that are produced around the world. It’s a favorite snack to cool down on a hot summer day for most adults and children. Yogurt is known as one of the miraculous foods or functional foods because it can give you some incredible benefits to your health.
Yogurt is an ancient probiotic milk product that is obtained by fermentation of milk-specific microorganisms. This fermented product contains live strains of good bacteria, usually from the Lactobacillus and Streptococcus strains, healthy for our gut.
Yogurt is usually purchased in refrigerated conditions since it contains probiotics that must be stored in particular storage conditions to keep these live organisms active.
If you consume yogurt that was not correctly stored, its probiotics may have already died. Unfortunately, in that case, you will get no benefit from it anymore but only a plain sour creamy snack.
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How to store yogurt?
Basically, you should always store yogurt in the refrigerator no matter what type of yogurt it is.
After purchasing the yogurt at the grocery store, you must immediately store it in the refrigerator. Avoid leaving it the yogurt at room temperature for more than two hours, the bacteria can begin to multiply at abnormal levels.
If you have already opened the package, that means you have already shortened its shelf-life. Make sure you cover it tightly if ever cannot consume all its contents. Uncovered open yogurt will dry out, and it can pick up any strong odors from different foods stored in the fridge.
Do not altogether remove the aluminum top of the yogurt’s package if you plan to leave some leftovers to be consumed later on the same day. You can re-use as a temporary cover to preserve the yogurt you left for your next meal of the day. Don’t let it stay in the refrigerator for days in that way. Instead, transfer the yogurt to a mason jar or a small airtight container to retain its freshness for a longer time.
Keep your yogurt in the fridge temperature of 4 ° c at all times. An opened pack of yogurt can last a maximum of about 2 hours. Hence, it is better to consume yogurt immediately after opening. Actually, there are times it can last for a few more hours, depending on the consistency of its storage temperature.
Storing yogurt in non-refrigerated conditions can consequently cause digestive disorders because these little bacteria may multiply in abnormal levels, and it may be harmful to you instead. Bacteria grow fast at temperatures between 40 degrees F and 140 degrees F.
Take note that you need to read the storage instructions provided on each product and follow the required, ideal storage conditions to avoid product damage.
Also, if you have mixed your plain yogurt with added sugar and fruits, this will increase the chances of bacteria growing faster, especially in unrefrigerated conditions.
Does yogurt go bad?
Yes. It can deteriorate earlier than you expect if you leave it in the wrong storage conditions. An opened pack of yogurt spoils faster than unopened yogurt.
Yogurt is full of life, and that’s good as long as it’s under control. The milk in yogurt is fertile material for growing microbes like bacteria and yeast and mold, so yogurt producers take great care in processing and packaging so that only the desired microbes are in the yogurt. Some of the information here can also apply to other dairy products like sour cream.
These tips cover commercially-produced yogurt which must follow certain rules covering production and testing . Home-made yogurt (pick one of these best yogurt makers) can be more unpredictable, for example not having an expiration date. The same signs of spoilage still apply, though.
What could be growing in that yogurt?
Yogurt can spoil in more than one way, depending on what might contaminate it. Yogurt production combines sterilization and deliberate inoculation with desired bacteria. The process faces risks of contamination. The Neogen Blog, a food-safety publication, explains that many wild species of bacteria, mold and yeast exist in ambient air. We go around inhaling them all the time. This accounts for the majority of contamination cases in yogurt processing.
Several species of bacteria can culture yogurt, usually strains of Streptococcus thermophilus and Lactobacillus acidophilus That name is descriptive; it’s a bacillus (rod-shaped bacteria) that lives on lactose and likes an acidic environment. When yogurt is cultured with the right bacteria, they raise the level of lactic acid which makes the yogurt less hospitable to other bacteria. But mold and yeast are fungi, which are completely different kinds of organisms.
Mold grows on the surface of the yogurt and spreads by threads. It may appear as green or black or orange spots, or as a blue fuzz. Mold can produce toxins, so it’s a sign that the yogurt is not safe. But is that absolute? Since the mold stays on the surface, if there’s just a little dot of it on the surface of a big tub of yogurt, you could spoon it out (and wash the lid to remove any spores). In that case, use it up before more mold grows.
Yeast is less visible, partly because it shows as white spots, which Neogen says are difficult to identify because they blend with the appearance of a dairy product. Yeasts can grow down into the product, below the surface. They can produce gases, which can make a product fizzy or bubbly.
How to tell if yogurt has gone bad?
First things first, you might be surprised to find some liquid on top of your yogurt. It is something that you should not worry about because that’s only the whey that has separated. That merely indicates that your yogurt is preservative-free. So, just give it a little stir to regain its uniformed texture.
Here are the signs you should check to tell if your yogurt has already gone bad:
Step 1: Check the expiration date
The most obvious thing to check is the expiration date. If the container is intact and the date has not passed, the yogurt is probably still good. Yogurt may still be good after this date, as long as it has been stored properly at a cool temperature.
The United States Department of Agriculture (USDA) food product dating fact sheet  says the selected expiration dates relate to food quality and not to food safety. The best-quality date is set by the manufacturers and retailers according to conditions like packaging, handling and storage.
Yogurt may spoil before the date if not stored properly; the stores keep it cold like any other dairy item so if the yogurt has been sitting at room temperature, it may spoil like other dairy items.
Step 2: Check the container
The care taken in yogurt production can’t protect the product once it’s out in the world. When you inspect a container, look for any signs that its original seal has been broken in any way – and that includes a container that has been sitting around after being opened. If the seal is compromised, look for more warning signs.
Also, check the container for cleanliness. Sometimes an intact container can be spattered with product from some other container that failed. This can also be true for other foods like plastic-wrapped meats.
Step 3: Check for signs of molds, discoloration, or change in texture (clumpy).
Look for any signs of mold spots or scum on the surface. Don’t forget to check the underside of the lid. If you see signs of mold, maybe you could skim it off, but it’s better to not take chances, and just throw it away. Discard the yogurt immediately if you find either one of these given signs
Step 4: Smell your yogurt to find out if it gives off any off-odor that is stale and sour. If yes, then throw it out.
Yeast is not as easily visible as mold but it produces gas, so intact seals on infected containers will show pressure by puffing out. (Pressure in sealed food containers is often a warning sign anyway.) If the container seal has been compromised, for whatever reason, another way to detect yeast is to smell the yogurt. The aroma should be slightly acidic, but not tangy like the aroma of rising bread dough.
Step 5: If your yogurt passed your smell test, you would have to taste it. If it tastes too sour, then it’s a sign that the yogurt is not at its best quality anymore, and you may want to throw it away.
Examine the texture. This brings up a distinction between yogurt products with or without active cultures. Pasteurized yogurt is like “processed” cheese which has no active culture so it’s stable. Natural yogurt, like “natural” cheese, has live cultures which continue to grow, just as natural cheese continues to ripen.
The US Food and Drug administration requires natural yogurt to list what cultures are present and their concentration in “colony-forming units.” The longer the cultures grow, the more the yogurt will thicken and taste acidic. It also develops some separation between the milk solids and the whey. You’ve probably seen some loose liquid on the top of older yogurt, and that’s not necessarily a sign of spoilage. You can simply pour it off.
Step 6: Finally, you better dispose of your half-opened yogurt for safety if it stays in your fridge for more than one week. And, if you have accidentally left it overnight at room temperature, toss it out too. It’s better to be safe from any risks of foodborne illness.
These basic tips should help you make a better-informed decision whether some yogurt is “bad” or still useable. Even if the yogurt isn’t in “best” condition, it might still be acceptable. As USDA says, “Consumers must evaluate the quality of the product prior to its consumption to determine if the product shows signs of spoilage.”
How Long Does Yogurt Last?
The shelf-life of yogurt depends on several factors: (1) the kind of yogurt, (2) the preservatives it has, (3) the storage condition before it reaches the store.
Each variety of yogurt has its unique ingredients, and it undergoes different kinds of preparation and processing. See this table on the shelf life of varying yogurt types in refrigerated and frozen conditions based on the “sell by date.”
|TYPE OF YOGURT||REFRIGERATED||FROZEN|
|Any opened pack of yogurt||7 days||1 month|
|Plain yogurt (unopened)||2 – 3 weeks||1 – 2 months|
|Greek yogurt (unopened)||1 – 2 weeks||1 – 2 months|
|Yogurt drink (unopened)||Up to 10 days||1 – 2 months|
|Low-fat yogurt (unopened)||1 – 2 weeks||1 – 2 months|
|Fruity yogurt (unopened)||Up to 10 days||1 – 2 months|
|Frozen yogurt (unopened)||N. A.||2 – 3 months|
One concern that is out of your control that can affect your yogurt’s shelf-life is how it was handled before it is displayed for sale. If there was mishandling that happened along the way, it could spoil your yogurt earlier than you expect.
Be warned that if the yogurt you purchased is free from preservatives, it will only last for a day or two.
When you purchase yogurt in the supermarket, check its “best before,” “best by,” or expiration date. Usually, yogurt can last for one to three weeks if unopened. Yogurt’s shelf life and its ultimate expiration date depend on various factors, like its sell-by or manufacturing date, preparation method, and storage instructions.
It is essential to read the storage information on specific types of yogurt. Each kind of yogurt may indicate different instructions on how to properly store the product, and it will tell you how to know if this specific kind of yogurt has gone bad.
Is it okay to freeze yogurt?
Yes, you can freeze yogurt. It is better to freeze yogurt in a heavy-duty freezer bag or in a covered airtight container. Once you defrost the yogurt in the fridge, you can keep for an additional 3 to 4 days before using it.
However, it will separate once thawed. To fix this little issue, stir it slightly to regain some of its texture but don’t expect it will be as smooth as freshly purchased. Thicker kinds of yogurts like Greek yogurt can freeze better than the ordinary ones.
Frozen yogurt is usually good to use in cooked or baked dishes, popsicles, smoothies, and desserts because the change in its texture will not matter all that much.