Does Yogurt Go Bad? Know Its Shelf Life & Storage Tips

How long is yogurt good for
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Yogurt is a dairy product that is a derivative of milk and must be stored and used within its pre-determined shelf life. How long is yogurt good for past the expiration date? Well, there are ways to extend this shelf life by up to a month by using deep freezing or refrigeration methods that are easy to do. Not following the recommended storage methods can result in the yogurt going bad and may cause illness and dehydration.

Yogurt, a dairy product that is popular all over the world, finds use in almost all the world’s cuisines. Have you ever wondered, how long is yogurt good for? After it leaves the dairy where it is made, how long does it take to reach the shelf? How to store it if you made your own yogurt? Read on and we will answer these questions as well as a few more.

Does Yogurt Go Bad?

Yogurt is formed by the action of bacteria in milk to turn it sour. So, before you even begin to check if it has gone bad, you should know that there are bacteria in it. Does yogurt go bad then? If some bacteria are already present, what harm can some more do?

Time and Temperature Affect Quality of Yogurt

Turns out, increase in bacteria is not the only way it can go bad. Being a milk product, time and warm temperatures are a bane to yogurt. Not just the bacteria, but fungus and other germs can grow on it, turning it bad. All the yogurt containers in the market come with a sell-by date and a use-by date, too. If stored properly all this while, the yogurt pack can be consumed without any doubt in mind for as long as 14 days after the sell-by date.

The U.S. FDA recommends that yogurt be kept refrigerated at 40 degrees F at all times. For every hour that it remains at room temperature, the chances of bacteria and germs causing food-borne illness increase. Bacteria double or triple every hour at room temperature. So keeping the yogurt out of the refrigerator beyond this time is not recommended.

Shelf Life of Different Types of Yogurt

So, how long is yogurt good for? In technical terms, what is the shelf life of a pack of yogurt? Open yogurt typically has shelf life of not more than one week to enjoy it at its peak quality. To enjoy it after the sell-by date mentioned on the container, it needs to be stored properly.

If the yogurt has been continuously refrigerated, then its shelf life could be extended by one to two weeks from the sell-by date. It is suggested by the FDA that yogurt that is properly stored can be consumed for up to 14 days after its expiry date, after which it may start to lose its quality.

If yogurt is left at room temperature for more than two or three hours, bacteria can grow rapidly on it, and the quality will deteriorate significantly. Any pack that has crossed the expiration date must be checked properly. A simple table to determine the extended shelf life is depicted below:

Shelf Life of Yogurt

Table for Shelf Life Of Different Types of Yogurt

Based on the way it is stored, the shelf life highly varies. Deep freezing it in the freezer can extend the life to almost one month even after opening the pack.

What Affects Storage Life of Yogurt?

How can you determine its storage time? Is there any mathematical or reasoning model to find out how long is yogurt good for?

The shelf life is affected by many factors, such as:

  • How you store the packs before opening them
  • The ingredients mixed with the yogurt for flavor
  • Where and how it is stored on the rack—exposure to bright light or a warm air draft from a ventilator can significantly affect the shelf life

Experiments conducted at various locations under varying temperatures have shown a rapid buildup of germs and bacteria that makes the yogurt go bad and unfit for consumption.

According to some research, the lactic acid bacteria survive better in plain whole milk yogurt rather than those with added sugars or fruits. So, we can say, the added sugars and fruits shorten the shelf life or impact the proteolytic activity of the bacteria. So, ideally, while extending the shelf life of your yogurt, whether it is plain or flavored may be one of the criteria.

How to Tell If Yogurt Is Bad

Like other dairy products, yogurt lasts for a small period if it is not stored properly. The best way to check if yogurt is of good quality would be to use your senses in the right way:

1. By Look & Smell:

First of all, you can tell by look and smell of the yogurt. Take note of any signs of spoilage like watery consistency, any clumpy structure, or sour smell.

2. Formation of Molds:

If molds are formed, it is best to discard the yogurt immediately. Do not to taste the yogurt if you see any of the above mentioned signs.

3. Water Content above Yogurt:

If the yogurt has a significant amount of water above it, trashing is your only option. If there is a limited amount of water, it can be mixed in the yogurt to keep its nutritional value intact.

What Happens if You Eat Expired Yogurt?

Sometimes, to avoid wasting food, we consume the expired food products that look edible. There is a possibility that you will experience the following side effects.

1. Diarrhea:

A common symptom of food-borne illness. If you experience this, make sure you consume a lot of fluids to prevent dehydration. If the condition persists for more than two days, consult your doctor.

2. Abdominal cramps:

Eating expired yogurt can result in abdominal cramps and pain. If it is severe and worsens with time, seek medical help immediately.

3. Vomiting:

In some individuals, consuming expired yogurt can lead to vomiting and physical weakness. In extreme cases, call your doctor at the earliest to prevent further loss of fluids and dehydration.

How to Store Yogurt for a Longer Shelf Life

Storing yogurt to prolong its shelf life is an essential kitchen skill.

1. Dehydrating Yogurt:

What if there was an emergency and you had no access to yogurt packs for many weeks. It is possible to dehydrate yogurt completely and freeze it to keep it fresh for long periods. This way, you can consume the yogurt as a frozen snack instead of the regular way of eating it.

2. Home-Made Yogurt:

You can also try to make it yourself at home. The only prerequisite is that you should have a small amount of yogurt (one to two teaspoons is enough). Take a flat bottomed container that fits well in your refrigerator and add half to one tablespoon of existing yogurt (depending on the quantity of milk) to it.

Then, pour warm milk to the extent that the container can hold, stir it, and set it aside covered on the kitchen table or platform. Let the good bacteria do its work and voila – you have homemade yogurt in a matter of hours. Be sure to refrigerate it as soon as the mixture has solidified to form yogurt.

The yogurt thus formed is plain. You can add fruit pulps or fresh fruits to it to give it your favorite flavor. Be careful, as you cannot really know how long such a yogurt is good for. But if stored properly, it can easily last you for a week, provided you do not finish it up earlier.

The Final Word on How Long Is Yogurt Good For?

Be it your regular pack of yogurt made in the best manufacturing dairy or a homemade one, it does have a shelf life.

Using a few kitchen tricks and storage methods, you can easily prolong its shelf life up to an additional week after its expiration date. This popular food is really versatile and nutritious, and finds use in main course cooking as well as desserts. Make sure you use fresh and appropriately stored products to prevent food wastage as well as unwanted illness.


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