How Long Does Kombucha Last?

Kombucha is a sweet and bubbly beverage usually flavored with a wide variety of fun and interesting ingredients. From strawberry to dragonfruit, cinnamon to sage; if you can imagine it, it’s probably made its way into a kombucha brew. 

This unusual drink, made from fermented sweet tea, has grown steadily in popularity over recent years and has been praised by foodies and nutritionists alike for its various health benefits. Filled with probiotics, B vitamins, and antioxidants it’s held up as a digestive aid, immune and metabolic support, and more.

With all of these claims haralding kombucha as an amazing health elixir, it’s unsurpirsing to find it readily available everywhere from health food stores to on tap at your local bar. 

But because brewing kombucha is a fairly simple process with few needed ingredients, we’re also seeing a rise in homebrewing setups as well. Which is great! Homebrewing kombucha allows you to avoid any of the potential additives in store bought varieties and lets you experiment with different flavor combinations.

However, whether you buy store bought Kombucha or brew your own at home, you’ve likely found yourself wondering at some point when that bottle tucked away in your fridge will go bad. Below we’ve outlined exactly what you need to know about Kombucha, expiration dates, and how to tell when it’s time to throw that bottle out.


How Long is Kombucha Good For?

The general consensus is that kombucha lasts for roughly 6-8 months after bottling, depending on a variety of factors. 

The process of making kombucha is a fairly simple one. Sweet tea – usually green or black tea – is brewed. Then, once cooled, a SCOBY (Symbiotic Culture of Bacteria and Yeast) is added to the tea along with some previously made strong, unflavored kombucha and then left to ferment over the course of 7 to 10 days. 

This fermentation process is what gives kombucha it’s low PH level and its signature, tart, vinegar-y bite. The standard PH level for a healthy batch of kombucha is between 2.5 and 3.5. It’s this acidity that gives kombucha such an impressively long shelf life. Much like vinegar, as long as the brew is protected from outside contaminants and is kept in a sealed container in a cold environment, kombucha can theoretically be kept indefinitely. 

However, this doesn’t mean that it will remain tasty and drinkable indefinitely. This is where that 6-8 month range comes from. The fermentation process continues even after bottling and after enough time has passed, your kombucha will turn into vinegar. This general timeline not only applies to unflavored kombucha but brews flavored with things like fruit juice, pulp, rinds, honey, sugar, and herbs as well.


Why do store bought kombuchas have a “Sell By” date?

If kombucha doesn’t technically go bad, you may be wondering why commercial brands have expiration dates printed on their labels. 

While federal law doesn’t require expiration dates to be printed on perishable foodstuffs, most grocery stores and food companies are members of the Grocery Manufacturers Association and the Food Marketing Institute. These organizations do require that these dates be listed on most consumable products being sold. Which means that commercially brewed kombucha gets labelled with conservative expiration dates despite it’s long shelf life.

If you have a store bought kombucha sitting in your fridge that is past its printed expiration date, it’s likely still good to drink. But always use your best judgement; if you notice an unusually strong or pungent taste or smell, or if there is anything resembling fuzzy mold in the container, it’s best to ditch it and opt for something fresher. 


How Long Does Kombucha Last After Opening?

We’ve now established that kombucha has a substantial shelf life. But how long does it last once you’ve opened that bottle? 

Most commercially sold kombucha brands recommend consuming it within 3-5 days after opening. This recommendation is actually a good one for homebrew as well. 

Much like soda, if left open kombucha will rapidly lose its natural carbonation and the flavors will become muted and flat. But this isn’t the only change kombucha will go through once opened. The introduction of oxygen and outside contaminants (think bacteria from your mouth, dust in the air, etc) will encourage the growth of bad bacteria which will lead to spoilage. Oxygen also helps speed up the fermentation process which, if left long enough, will turn your kombucha into vinegar. 

If the kombucha is in a bottle or can that cannot be resealed, it’s best to drink it immediately. The ability to reseal the bottle will allow you to enjoy your kombucha over a period of a few days with minimal loss of fizz, flavor, and fewer concerns of contamination. 


How to Determine Shelf Life of Kombucha?

When brewing and bottling your own kombucha there are two things you need to keep track of to determine if your kombucha is still good: mold growth and the development of vinegar.


Kombucha contaminated with mold

Kombucha almost always has some form of floaties suspended in it. These can be in the form of brown strings, gels, sediment at the bottom of the bottle, or brown chunks. These are usually remnants of the SCOBY used to make the kombucha or the development of a new SCOBY. If you see these in your bottled kombucha, there is nothing to worry about and are a sign of a normal, healthy kombucha. 

Mold is something different and is one of the biggest worries for kombucha shelf life. Especially when it’s been homebrewed and therefore hasn’t gone through the various tests and procedures that make the store bought versions more stable. Homebrewed kombucha is amazing because it’s fresher and more alive with cultures and probiotics, but also leads to the potential for more contamination. Mold happens when bad bacteria is introduced into the brew and are given the chance to reproduce and thrive. This can happen through various routes from using unsanitized tools and equipment during the fermentation process to drinking directly from the bottle. 

Checking your kombucha regularly for mold growth is important for determining if it’s still safe to consume. If there is anything that looks fuzzy or colored (think black, blue, green, or pink) growing inside the bottle? Definitely time to toss it out. 

Vinegar: Taste and Smell

The second thing to check for is your kombucha turning into vinegar. This is a little less straightforward but just as important. 

Kombucha continues to ferment after bottling. If you open a bottle and it smells unusually strong, yeasty, sour, or pungent – it may be best to ditch it and grab a fresher batch. While kombucha naturally has an acidic bite to it and smells a little like vinegar, an unusually strong smell may indicate that your brew has either crossed that threshold over into vinegar or that it has been contaminated and has gone rancid. 

This idea also applies to taste. Flat or muted tasting kombucha is, while less ideal, okay to drink. This usually indicates that the bottle or container has been open for a little while, decreasing its freshness. But any strong or unpleasant smells or tastes should be considered a sign of either too much fermentation or contamination. If you can’t swallow your kombucha because of how acidic or bitter it is, that’s a good sign that it’s gone bad.

PH Strips

The low PH level of kombucha is the key reason why it can be kept for such a long time. One way to make sure that your kombucha is within the safe and desired PH level range is to use PH strips. They are widely available online and are easy to use: just pour a small amount of kombucha into a glass and dip a PH strip into it. Then you just need to compare the strip to the brand’s listed instructions to figure out the PH level. If it’s within that desired 2.5 to 3.5 range, you’re likely in a good place with your brew.


Can Kombucha Go Bad If Not Refrigerated?

The primary purpose of refrigeration is to slow fermentation and prevent bacteria growth. 

This is especially true for homemade kombucha. Store bought kombucha is commonly pasteurized, sometimes watered down, has had the alcohol removed, and often has yeast inhibitors that prevent continued fermentation. This all makes the store bought versions more shelf stable and prevents the kombucha from continuing to ferment as it sits on grocery store shelves. 

Homebrewed kombucha is filled with live yeast and bacteria which, once introduced to colder temperatures, go into a dormant state. While this slows down the fermentation process, it does not stop it entirely. Fermentation still occurs but at a much slower rate than it would at room temperature. Allowing it to be kept for much longer. 

If kombucha is stored outside of the refrigerator, fermentation will continue to happen at a rapid rate; increasing carbonation, alcohol content, and PH level. Not only does this eventually risk a vinegar situation and potential mold growth, but it also has the potential of causing the container to explode due to the build up of carbonation. 

Because brewing methods can vary so much in homemade kombucha processes, we really can’t put down a specific time range for how long your kombucha will be drinkable when stored at room temperature, or in even hotter environments like a car in summer.  The best practice is to always store your kombucha in the fridge or a cool place, and if it has spent time in a warmer environment, check for mold or a significant change in smell or flavor before drinking. Store bought should typically last longer in warmer environments than home brewed kombucha, but always check for spoilage first just in case.


Can You Drink Expired Kombucha?

The short answer is: yes. Since kombucha does not technically go bad, as long as it has been properly handled and is absent of mold, it can be consumed at any time. 


What happens when you drink bad kombucha?

Unless you have underlying health conditions that make you particularly susceptible, drinking bad kombucha is unlikely to cause severe health issues.

Accidentally consuming a small amount of mold of bad bacteria is likely to be passed without much notice. As long as you have a healthy gut and immune system, the most you’ll experience from a mouthful of moldy kombucha is some nausea from the horrible taste. If you happen to consume more than a mouthful or two, or happen to have underlying health conditions that make you particularly susceptible, you may experience anything from simple food poisoning to more serious reactions.


Final Thoughts

Kombucha is a healthy and delicious way to support your digestive system and overall health. As long as you keep an eye out for the potential problems, it’s very easy to keep on hand for whenever you find yourself needing a boost.

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