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How To Tell If Kefir Is Bad?

How To Tell If Kefir Is Bad?

If you’re trying to eat healthily, you’ve surely tried adding kefir to your diet. It’s got a lot of vitamins, essential amino acids, and essential minerals. It’s also packed with healthy bacteria.

This beverage is native to the Northern Caucasus region, Eastern Europe and Russia. From there, it spread to the whole world at the beginning of this century.

There are two types of kefir:

  1. First, there is milk kefir – as its name says, it’s made from milk and contains probiotic bacteria. Milk kefir has a sour taste, and it can also be carbonated. 
  2. The other type is water kefir. This kefir is made from water, which means that it’s dairy-free. The taste of this kefir is sweet and a bit fermented. People mostly prefer flavored water kefir.

Here we will only be talking about milk kefir because it’s far better known than its water counterpart.

If you’re new to this healthy, refreshing beverage, many questions may arise like:

How to tell if kefir is bad? How to store kefir? Is it healthy? How else can you use it?

Here you will get the answers to all your questions, and much more, so read on!

How To Tell If Kefir Is Bad?

Kefir is a fermented milk product, just like sour cream or yogurt, and it behaves the same way. It’s made from microorganisms called kefir grains, which are put into milk to ferment. 

There are a few ways you can tell for sure that your kefir has gone bad:

  1. Color changes: The most obvious one is mold forming in the kefir. The amount of mold can vary from a few tiny spots to the whole kefir being moldy. 
    • The mold can turn up in different colors. It can be pink, green, or even black.
    • Some people just scrape off the moldy parts and drink the rest, but we don’t recommend doing that. It’s simply better to throw the bottle and buy another fresh one.
  2. Changes in texture: If the kefir grains separate from the milk and fall to the bottom, then it’s probably gone bad.
  3. Changes in taste and smell: Kefir is a sour drink, so it can be hard to tell when it’s gone bad. Because kefir is made of living organisms, its taste will become stronger as time passes. If it gets too sour for your taste, you can either throw it away or use it in a recipe where the flavor will fit perfectly.
    • If your kefir starts to smell like spoiled yeast or milk, that means it’s no longer good to drink too.

How Long Does Kefir Last?

The amount of time kefir stays fresh depends on whether it’s opened or unopened. 

Also, temperature plays a significant role. Like yogurt, kefir also has probiotic bacteria in it. The bacteria make it very healthy but also cause the kefir to go bad faster in warmer temperatures. 

Storing it in cold places will slow down the growth of bacteria and kefir grains. This will keep the kefir fresh for longer.

In the fridge, an unopened bottle of kefir is sure to stay fresh until the best-before date on the package. You can add up to a week to that date if it stays unopened.

Kefir will last for 1-2 months if you freeze it in an airtight container, but that’s not preferable because it will lose its nutrients.

If you leave it at room temperature, it will start to go bad in a day or two.

After opening the bottle, the time kefir stays fresh is much shorter. 

If you open it a few days before it expires, you can expect it to stay fresh for another 4-5 days

If you open it on the day it expires, or a couple of days later, you should use it within 24 hours.

What Nutrients Does Kefir Have?

Kefir is very rich in many nutrients that are healthy for you. These include:


  • Calcium – because kefir is made from milk, it contains a high amount of this mineral, which is vital for keeping your bones healthy.
  • Potassium – This mineral is necessary for the normal function of your heart, and kefir has a bunch of it.
  • Sodium – An essential mineral for all animals. It’s in charge of keeping your blood pressure stable and blood volume.
  • Zinc – vital for the normal function of almost every organ in your body. It’s also crucial for child development, so kids drink up that kefir!


  • Vitamin A – This vitamin keeps your eyesight sharp and your immune system as strong as possible.
  • Vitamin C – This is the main vitamin responsible for fighting off infections in your body.
  • Vitamin D – works alongside calcium to keep your bones healthy.

Other Nutrients

  • Protein – kefir is an excellent source of protein, which is vital for building muscle in your body.
  • Healthy fats – the milk in kefir provides healthy fat, which is an essential nutrient.
  • Good Bacteria and yeast – kefir contains a handful of healthy bacteria and yeast which take care of your digestion and gut health.
Does Kefir Go Bad

Health Benefits Of Kefir

There is no doubt that kefir is one of the healthiest foods you can consume. It has a wide range of benefits for your health.

Kefir is useful for calming down your stomach when you have gastrointestinal problems. This is due to the healthy bacteria it contains, which help your stomach digest food.

Also, kefir can kill off harmful bacteria that you may consume when you eat food. It produces ethanol and organic acids, which are deadly to some types of bacteria.

If you get sunburnt or burn your skin in any way, you can put kefir on the burnt spot. It has anti-inflammatory properties that help heal your skin.

Kefir also helps with cancer prevention. It acts as an antioxidant, preventing tumor cell formation.

Your immune system will also work much better if you drink kefir. Because it’s rich in vitamins and minerals, kefir will keep your immune system strong, so you will have less chance of getting sick.

It will keep your heart and liver healthy. Kefir is useful for lowering your cholesterol and triglycerides. These affect your liver and heart function, so decreasing them is very important for general health.

People who are lactose intolerant can drink kefir without any problems. It has low lactose levels because the bacteria and yeast in the kefir consume the lactose in the milk. Lactose intolerant people will have no problems enjoying this refreshing drink.

Culinary Uses For Kefir

Although kefir is a drink, it can also be used in many different ways to please your taste buds:

  • Salad dressing: because of its sharp and sour taste, kefir is good to use as a salad dressing. If you’re using buttermilk, for example, try using kefir instead. Besides the sharp flavor, you’re getting a bunch of probiotics too.
  • Smoothie: you can use kefir for making your favorite smoothie. It’s similar in texture to yogurt, so next time try making a delicious kefir smoothie with some fruit.
  • Homemade ice cream: if you love making your own ice cream, try using kefir as your main ingredient. The sour flavor mixed with sweet fruit will be quite refreshing on those hot days.
  • Cereal: kefir is great for soaking your breakfast cereal in it. Next time use it instead of milk; you’ll love the change. The same goes for overnight oats.
  • Soup: use kefir as a base the next time you’re making soup. The salty-sour taste will grow on you in no time.

How To Tell If Kefir Is Bad? – Final words

In general, kefir has a short shelf-life. To preserve your kefir’s freshness, you should keep it in the fridge because that will slow down the fermentation process. This will keep your kefir fresh for a couple of weeks.

You can also freeze your kefir, which will prolong its freshness to a few months, but at the cost of losing nutrients.

The obvious sign of spoilage is mold forming in the kefir. You can scoop it off and drink the rest of the kefir, but we don’t recommend that. Mold can change the quality of the whole kefir, so it’s best to throw it away in that case.

Also, the separation of kefir grains from the milk and a change in taste or smell is a good sign of kefir going bad.

You can drink kefir even after its best-before date if you like the strong sour taste. If it’s too much for you, just get a new fresh bottle.

If you have more kefir than you can drink, be sure to use it to make some tasty snacks and salad dressings, don’t let it go to waste!