How long does Yoghurt Last? [And How Best to Store it for Longevity]

Yoghurt is easily one of the most commonly consumed milk products, not just in the country, but in the world as a whole. The one characteristic that stands out about milk, aside from its nutritional benefits and great taste, is that it has the tendency to go bad real quick, especially when it is unprocessed or poorly preserved. Seeing as yoghurt is primarily a milk product, it is only expected that it has a short life span, especially when it is not preserved right. So, how long should you expect yoghurt to last?

When you buy yoghurt from the store, you can expect it to last you anything between a week and two months depending on whether or not you open it right away, and whether you store it in the refrigerator or in the freezer. Frozen, unopened yoghurt has the tendency to keep longer, even lasting months past the sell by date, because the conditions make it a lot harder for microorganisms that promote spoilage to thrive.

To understand why yoghurt would potentially go bad so fast, we need to understand exactly what converts regular milk into the thick and smooth consistency that yoghurt is. Yoghurt making essentially entails processing and introducing live cultures in the form of bacteria into milk, and providing ideal conditions for the said bacteria to thrive.

Once introduced into the milk, the bacteria initiate a fermentation process that causes the milk to ‘thicken’ and achieve that characteristic taste and smell, as well as consistency. Here is the thing – once the yoghurt has been packaged, the fermentation process could actually continue, leaving you with yoghurt that is much lighter in consistency, and that has a sour taste.

One of the easiest ways to make certain that yoghurt does not go bad too quickly is to refrigerate it since low temperatures ‘inactivate’ the bacteria, allowing your product to maintain its quality for some time. However, there are multiple factors, apart from the said bacteria, that could actually cause yoghurt to go bad fast. Below is a short list of factors;

  • Air (Oxygen)

Before breaking the foil seal on your recently purchased yoghurt, it remains fully air and water tight, making certain that nothing from the outside can penetrate through. Once the seal is broken, it paves way for the introduction of oxygen which encourages the present bacteria and those in the air to start growing and thriving in the yoghurt. The waste generated by these bacteria causes it to go bad, and can also cause tummy trouble when consumed. This is largely why opened yoghurt has a much shorter life span than sealed yoghurt.

  • Heat (High temperatures)

As earlier stated, lower temperatures actually discourage most microorganism from thriving, but when heat/ warmth is introduced, they resume this activity, causing the fermentation process to continue. When yoghurt is unopened but stored in room temperature, you may notice a certain swelling on the lid – an indication of pressure build-up from within. This is indicative of excess fermentation and spoilage.

So, how can you tell that yoghurt has gone bad?

As with most other foods that we know, there are certain characteristics to check for to know whether or not a certain product, yoghurt in this case, is still good to consume. To know whether or not yoghurt has gone bad, here are a couple things to look out for.

Physical indicators of degradation

Food spoilage is generally easy to spot, and with yoghurt, you may notice a certain separation between the liquid (whey) and solid (milk protein & fats) phases. This is at times normal, especially when there is not much separation, and the whey is actually at the top,but when you can see that the solids are all at the top of the container, you will know that the yoghurt has gone bad.

Another physical indicator, especially in yoghurts that are more solid, is the growth of mold. You may notice mold on the surface of the yoghurt, and at this point, you may have to toss the entire tub out.

Olfactory indicators

In most instances, when yoghurt has gone bad, you will notice an acidic smell. On the onset of spoilage or extreme fermentation, spoilt yoghurt will start to smell a bit like sour cream. When you can detect this smell, it is time to get rid of it.

What you may or may not know is that different types of yoghurt bear varying shelf lives, and a couple are broken down in the table below.

 

Type of Yoghurt
Life Span in Refrigerator (Past Sell By Date)
Life Span in Freezer (Past Sell By Date)
Regular & yoghurt
14 to 21 days
1 to 2 months
Drinkable yoghurt
7 to 10 days
1 to 2 months
Greek yoghurt
7 to 14 days
1 to 2 months
Low fat yoghurt
7 to 14 days
1 to 2 months
Yoghurt with fruit
7 to 10 days
1 to 2 months
Opened/ unsealed yoghurt
7 days
1 month

 

So, how can you make your yoghurt last longer?

One of the most important and effective ways of keeping your yoghurt fresh for longer is to make sure that you refrigerate it after purchase, especially before you open it.This allows it to maintain its quality for longer periods of time.

Once open, make certain to reseal it with the reseal foil it comes with, and keep it in a cool environment away from heat. Also, keep from opening it every so often since this gives harmful bacteria more chances of getting into the yoghurt, resulting in contamination.

 

Conclusion

Yoghurt is an incredibly delicious and healthy food, and this is likely why it is a favorite in many households across the globe. One of the least convenient characteristics about milk and many milk products is that they tend to keep but a short time, and even adding preservatives does not make much difference. If you hope to enjoy your yoghurt a considerable amount of time, refrigerate it as soon as you open it, or try and keep it sealed until you are ready to consume it.

 

FAQs

Does it mean that yoghurt is expired after the sell by date?

No, it doesn’t. if you an, though, try and consume it before then. However, you should refrain from consuming yoghurt after its Use By date.

Can live bacterial culture help yoghurt keep longer?

Yes, they can. They actually act as natural preservatives before they die off.