What Happens If You Add Vinegar to Kombucha While Brewing?

Kombucha, the tangy, fizzy fermented tea, has become increasingly popular for its potential health benefits and unique flavour.

But if you're brewing kombucha at home, you might wonder about the various ingredients and methods you can use.

One common question is: what happens if you add vinegar to kombucha while brewing?

In this blog post, we’ll explore the role of vinegar in kombucha brewing, the effects it can have on your brew, and whether or not it’s a good idea to add it to your kombucha.

Why People Consider Adding Vinegar to Kombucha?

Vinegar is a highly acidic liquid, typically containing around 5-7% acetic acid. Because of its acidity, some people think that adding vinegar to their kombucha brew could:

1. Speed Up Fermentation: The idea is that the acetic acid in vinegar could kickstart the fermentation process, leading to faster results.

2. Prevent Mold Growth: The high acidity could help create an environment that is less hospitable to mold and other harmful bacteria, protecting the SCOBY (Symbiotic Culture of Bacteria and Yeast).

3. Rescue a Weak SCOBY: If you have a SCOBY that isn’t thriving, some might think vinegar could help balance the pH and give the culture a boost.

But does adding vinegar really work this way? Let’s take a closer look.

What Happens When You Add Vinegar to Kombucha

1. pH Levels and Fermentation:

- Kombucha needs to maintain a specific pH range—generally between 2.5 and 4.5—to ferment properly.

Adding vinegar, which is highly acidic, can significantly lower the pH of the brewing kombucha.

While this might seem like a good thing, dropping the pH too low can actually harm the SCOBY and slow down or even stop the fermentation process.

The microbes in the SCOBY prefer a certain balance, and too much acidity can disrupt that balance.

2. Impact on Flavour:

- Vinegar has a strong, distinct flavour. Adding it to kombucha will affect the taste, potentially making it overly sour or harsh.

The subtle balance of sweet and tangy that makes kombucha enjoyable can be lost if vinegar overpowers the brew. Instead of the nuanced flavours that come from natural fermentation, you could end up with a brew that just tastes like vinegar.

3. Potential Risks:

- Introducing vinegar, especially if it’s store-bought, can also introduce unwanted bacteria or yeasts to your kombucha.

Even though vinegar is acidic, it isn’t guaranteed to be free from other microorganisms that might interfere with your kombucha’s fermentation. This could lead to contamination or spoilage of your batch.

4. No Benefit to the SCOBY:

- While it might seem logical to add vinegar to "rescue" a weak SCOBY, it’s unlikely to help.

The SCOBY thrives on the specific environment created by kombucha fermentation, not by the addition of foreign acids. In fact, a weak SCOBY is more likely to be further stressed by the introduction of vinegar, leading to an even weaker brew.

When Vinegar Is Useful in Kombucha Brewing

Although adding vinegar directly to your kombucha brew is not recommended, vinegar does have some uses in the kombucha-making process:

1. Cleaning Equipment:

- Vinegar is excellent for cleaning your brewing jars and utensils. Its acidity helps to sanitize equipment, reducing the risk of contamination in your brew.

2. Starter Liquid:

- Some brewers use raw, unpasteurized apple cider vinegar as a starter liquid when they don’t have enough kombucha from a previous batch.

However, this is more of an emergency option and should not be a regular practice, as the best starter liquid comes from well-fermented kombucha itself.

3. pH Adjustment (Cautiously):

- In rare cases, if you are dealing with a high-pH environment that refuses to drop after multiple brewing attempts, a tiny amount of vinegar (such as a teaspoon in a gallon) might help. But this should be done with caution and as a last resort.

The Best Practices for Brewing Kombucha

For optimal results, stick to the traditional method of brewing kombucha:

- Use high-quality black or green tea.

- Add the right amount of sugar, which feeds the SCOBY.

- Include a cup of starter tea from a previous batch to ensure proper fermentation.

- Keep your brewing environment clean and free of contaminants.

If your SCOBY is healthy and your brew is kept at the right temperature (between 68°F and 85°F), your kombucha should ferment successfully without the need for vinegar.

Conclusion

Adding vinegar to kombucha while brewing is generally not recommended. While it might seem like a way to boost fermentation or protect against mold, it can actually disrupt the natural balance of your brew, leading to an overly acidic, harsh-tasting kombucha—or worse, a stalled fermentation process.

Stick to the tried-and-true methods of kombucha brewing, and your SCOBY will reward you with delicious, tangy tea every time. If you’re facing challenges with your brew, consider other troubleshooting methods, like adjusting temperature or sugar levels, rather than resorting to vinegar.

If you want to know a little bit more, then just watch the video below.

Happy brewing!