A few days ago I was brewing kombucha like normal and for some reason the batch turned out a little different than most. It tasted harsh like vinegar rather than sweet and acidic like it should. Which led me to wonder, what causes kombucha to sometimes taste like vinegar and how can you fix it?
All kombucha has some level of acetic acid, the main component of vinegar, in it. If a brew of kombucha is fermented for a longer amount of time, its bacteria and yeast culture will produce more acetic acid, which will make the kombucha taste more like vinegar.
In this article I’ll not only cover why your kombucha tastes like vinegar, but more importantly give you some tips on how to keep it from happening in the future. Plus I'll give you a few ways you can use the kombucha vinegar you have now. Let’s get started!
Why Your Kombucha Tastes Like Vinegar
The reason that kombucha sometimes taste like vinegar is because of a chemical called acetic acid. You've come in contact with acetic acid if you've ever used vinegar, which is just acetic acid diluted with water.
The acetic acid in kombucha is created by the living bacteria and yeast culture called a SCOBY (Symbiotic Culture of Bacteria and Yeast) during the process of fermentation.
If kombucha isn’t fermented at all it won’t have any acetic acid in it and will just be sweet tea. And if it's fermented for too long it will have lots of acetic acid in it and turn into vinegar.
Regularly brewed kombucha will usually be 1% acetic acid, which is much less than vinegar, which is often 4-7%. The goal of kombucha brewers is to ferment their booch to a point where it has some of that bitter vinegary kick to it, but still tastes sweet and is easy to drink.
So while a slight vinegary taste in kombucha is completely normal and a sign that the drink was made right, the vinegary taste of kombucha can become overpowering and undrinkable when the bacteria culture ferments too much and produces too much acetic acid.
What causes this to happen? One of three things below.
The 3 Main Things that will Cause your Kombucha to Taste Like Vinegar
1. Too long a fermentation
As I already outlined above, the longer kombucha ferments the more acetic acid is created by the bacteria and yeast culture and the stronger the vinegary taste will be.
2. Too warm a fermenting temperature
One big factor that many people forget about when making kombucha is the role of temperature on the activity levels of your bacteria and yeast culture.
Basically the warmer the temperature of the room you're brewing kombucha in, the faster the SCOBY is going to ferment the kombucha.
So while here in the cold state of Michigan my kombucha may take 2 weeks to reach 1% acetic acid, in a warmer area it’ll probably only take 1.
3. Too big of or too many SCOBYs
The SCOBY is what makes the kombucha into vinegar, so it makes sense that extra SCOBYs would lead to extra vinegar. If you’ve been brewing kombucha for a while and your SCOBY has grown more than a couple inches thick your kombucha is going to produce acetic acid a lot quicker than it used to.
Ok so now you know what causes your kombucha to taste like vinegar, but what you probably really care about is how to fix it. So lets talk about that!
How to Keep Your Kombucha from Tasting Like Vinegar
Ferment for Less Time
The easiest adjustment you can make to keep future kombucha brews from tasting too vinegary is to just ferment them for less time.
Normally it’s recommended that kombucha is fermented for 10-14 days, but this can vary greatly depending on the temperature of where you live and the activity level of your SCOBY. The easiest way to keep it from fermenting too long and becoming too vinegary is to just taste the brew every day.
The best way to do this is to stick a straw into your brewing vessel, plug one end with your finger, and pull out some booch. This way you don’t have to worry about spilling any kombucha or contaminating your scoby by trying to pour or scoop out a glass.
In the first few days of fermentation the kombucha will taste really sweet, but after a week or two you’ll notice the sweetness disappearing and the bitter and vinegary kick becoming more evident. Just consider the fermentation done when you feel like the sweet and bitter flavors are at a balance you like.
Ferment at a Cooler Temperature
As I talked about earlier, the warmer the temperature of the room your kombucha is brewing in the faster it’s going to ferment and harder it’s going to be to keep it from over fermenting.
If your kombucha has been tasting too vinegary and the room you ferment it in is above 75 degrees F (24 C) you might want to move it to a cooler part of the house. For most people their basement is cooler than other rooms, so this could be a good place to leave your brew.
Just be sure to keep it in an environment above 65 degrees F (18 C) since temperatures colder than that can completely stop the fermentation process.
What if my Kombucha Already Tastes Like Vinegar?
The tips above are for how to keep your kombucha from tasting like vinegar in future brews, but what if you’ve already made this mistake of over fermenting your kombucha and don’t want to waste it? If you’re in this situation, don’t worry, there are plenty of ways to make use of vinegary kombucha!
Water it Down
The first thing you can do to fix over fermented, vinegary kombucha is to just water it down before drinking it. Sure it’s not going to be the most delicious and flavorful glass of kombucha you’ve ever had, but at least it will be drinkable and you’ll be able to get all the health benefits without wasting the stuff.
Neutralize it
Neutralizing your kombucha definitely takes a little more effort than watering it down, but it will have a slightly better flavor and reduce the vinegar taste just as well.
If you’re not sure what neutralization is, it’s basically a chemical process where a base is added to an acid (in this case acetic acid) to create water.
Now obviously we don’t want to turn kombucha into water, so we’ll only neutralize it slightly to lower the acidity enough to be enjoyable to drink. You can do this by adding calcium carbonate or potassium bicarbonate slowly to your vinegary booch. You should be able to find either of them at any health store that sells vitamins and minerals.
While watering down or neutralizing your vinegary kombucha can make it more drinkable and keep you from wasting it, I think that the best use for your over fermented kombucha is to give up on drinking it and instead just use it as vinegar. Here’s a few ideas:
Starter Tea
My favorite use for over fermented kombucha is as a really strong starter tea for future brews. Starter tea is just a cup or two of kombucha saved from previous brews that is added to every new brew of booch to create an acidic environment and prevent mold growth.
By using especially vinegary kombucha as starter tea your brews will start extra acidic and be better protected against mold.
Salad Dressing
Another great use for vinegary kombucha is as a salad dressing. It'll give your salads the same tangy kick as balsamic vinaigrette but with a slightly sweeter and fruitier flavor.
You can either dress your salad with raw vinegary kombucha or you can infuse the vinegar with herbs, garlic, and spices to add more flavors.
Glazes and Marinades
You can also use kombucha vinegar to glaze and marinade vegetables and meats. To glaze vegetables like onions, carrots, potatoes, brussels sprouts, and squash follow the recipe below.
Place the vegetables in a pan with water and the kombucha vinegar. Bring it to a boil and then cover and reduce the heat to medium and let it cook for 10 minutes.
Now remove the lid and raise the heat back up to a boil again. Allow the water to boil away and the vinegar to reduce and glaze the veggies, which should take about 5 to 7 minutes.
Once the vegetables are glazed to a sweet, rich brown color add butter to the pan and turn and coat the veggies with it. Then season with salt and pepper and serve!
Final Thoughts
While accidentally over fermented and vinegary tasting kombucha may feel like a waste of time and effort, there are lots of ways to make use of vinegary kombucha and keep it from going to waste. Plus as long as you keep track of the fermentation length and temperature of your fermentation and size of your SCOBY your kombucha shouldn’t develop a vinegary taste ever again.
If you found this article helpful and would like to learn more about kombucha, brewing tips, and how you can use it to improve your health be sure to check out the rest of my website!
Have a great day!