Q: My Culture looks weird, is it ok?

A: Yes! While mold and other abnormalities can occur during brewing, it's truly quite rare. However, let's face it, kombucha cultures look strange and oftentimes it is confusing to tell what is happening during those initial few brews. First, don't stress about mold - most likely what you are seeing in your brew is air bubbles or yeast. The yeast looks especially odd because they can appear blue, green, even pink and orange sitting underneath the iridescent culture that grows in across the top over the first few days of brewing.

Check out our gallery of healthy and unhealthy cultures below (click on a picture to enlarge it) and see if your culture looks like any of these. If you're still not certain your brew is progressing as it should, please send an email with a picture to questions@thekombuchashop.com and we're happy to give a second opinion!

Healthy cultures

A healthy culture may have brown, stringy or blob-like debris attached to it. It can be bumpy or smooth, and have clear dots or bubbles. When you drop your new culture into the brew jar, it can sink to the bottom, float in the middle or on top - all location are just fine and will ferment your kombucha just the same. 

Unhealthy Cultures

Similar to molds you would see on bread or cheese, an unhealthy culture will develop fuzzy blue, green, or white mold. Again, this is very rare, and is usually caused by accidental inoculation from airborne spores in the house, or a culture that is incorrectly stored without enough starter tea to rest in, thus exposed to oxygen for a prolonged period of time instead of resting happily in plenty of liquid kombucha. If you're still unsure if you have mold present, please send us a picture at questions@thekombuchashop.com and we'll give you a second opinion!

Q: I'm not sure if the temperature gauge is working... why is it not showing any readings?

A: If your temperature gauge isn't showing any readings, it's very likely that the temperature of the liquid is falling somewhere outside of 58-88 degrees, so it can't read it.  (Typically, this happens when mixing the warm sweet tea and the liquid is still above 88 degrees) 

If the temp gauge is reading 2 or 3 colors, this means the actual exact temperature is lying somewhere in between the numbers on the gauge. Green indicates the correct temp. If green is not visible, the temperature will be midway between what is illuminated by tan and blue.

Q: How can I keep my brew warm in the winter time?

A: You can use a heating pad placed around it, flip it on the lowest setting for a few hours a day. You can also place a towel or blanket (wool if you have it) around the jar to insulate it. If you don't have a heating pad, setting up your brewing space next to a heating vent or high on a shelf in a warm room usually does the trick . 

We are located in Madison, WI so we're definitely privy to brewing in cold temps! Here are some of our top tips for brewing in the winter time:

1) In the winter, we prefer to move our jars up to a high shelf in a warm room. Like on top of cupboards or a tall bookshelf. Sometimes this means setting up the brew jar upstairs where it can be warmer if you have a multi story home. 

2) If you brew jar is resting on a cold countertop, place a book or cutting board underneath it for insulation

3) If taking those steps doesn't get the temperature above 68, we do recommend using a heating pad, setting it on its lowest setting, and wrapping it around the jar. This can be very effective in maintaining a consistent temperature in the mid 70's. 

The trick with using a heating pad it checking in on it so that it doesn't get too warm. Our brewing kits come with a temperature gauge so it will be easy to always read the temperature on the side of the jar. If your heating pad keeps the brew too warm (in the mid to upper 80's is too warm) then just flip it on for only a few hours a day.

You can keep a towel wrapped around the heating pad and jar so once you flip off the heating pad it will help to retain some of that heat for a few hours after. 

As for the second fermentation - it is less necessary to keep the temperature in the 70's. Simply store your kombucha bottles somewhere they will stay above 68 degrees. If you want to move the second ferment along quicker, then store them somewhere warmer.

Q: What is the importance of temperature when brewing?

A: It's important to keep your brew jar as close to 74-76 degrees as possible, that is when the culture produces the most balanced ratio of yeast to bacteria. As you'll soon find, Kombucha brewing is all about finding balance. 

Colder Temps:

It's fine if your brew drops as low as 68 degrees. However, if it goes below 68 degrees for an extended period of time it can be more prone to develop mold, as the bacteria and yeasts will start to go to sleep. The colder it is, the longer it will take to brew. And vice versa, the warmer it is, the faster it brews.

Warmer Temps:

If your home is very warm in the summer time, its important to keep your brew jars somewhere cooler they won't get too warm. It's best to not let your brewing jars stay above 84 degrees for too long or your yeasts will begin to overpopulate and throw your brew out of whack.

Be sure to keep any heating methods like a heating pad in check. If leaving your heating element on all the time is keeping the temperature too warm, simply turn it on a for a few hours a day and wrap a towel around it to insulate. 

Q: Do I have to use caffeinated tea?

A: Yes. Kombucha cultures have evolved to feed on caffeinated tea from the Camellia Sinensis tea family - meaning black, oolong, white or green teas. Without one of these teas high in caffeine and tannins, your culture will grow weak and eventually die. Avoid flavored teas like Chai and others with additional oils and herbs as they weaken the culture and encourage mold growth (No Yogi Tea blends!). We recommend using a pure black, oolong, white or green tea. A blend of green & black tea, or oolong & black tea, make a particularly great combo both in flavor and for creating a healthy culture and brew. Black tea is the highest in tannins, so if you notice your culture growth has stagnated after a few brews, mix back in some black tea to your tea mix.

For reference, our custom TKS Tea Blend is a mix of loose leaf oolong and ceylon (black) tea. Ceylon is a traditional black tea from Sri Lanka and Oolong is a mix in itself of fermented black and green teas. Oolong is a traditional Chinese tea and is what Kombucha has been historically brewed with throughout time. Use organic and fair trade loose leaf teas when possible, they make all the difference in the quality of your final brew!

Q: My brew has been sitting for over a week. I tested the pH per the directions and the reading was too high. What do I need to do to get the pH to the recommended 2.5 to 3.5?

A: The slow growth/fermentation could be due to a low temperature. If you are brewing at the lower end of the average (70/72 degrees), let it brew for another 5-7 days and then give it another taste test and pH strip test and see how everything looks! Brewing at a lower temperature will work fine,  it just might take a little longer.

Q: How hot is too hot for a kombucha culture?

A: A culture can hit 95-100 degrees for a short time and survive just fine (like during shipping). Optimally, you want to be able to keep it consistently in the mid 70's, or upper 70's at the most. If the temperature goes above 88 for more than a few hours, the bacteria get out of control and throw off the brew. That is why our temperature gauge stops reading above 88 - because the temperature really shouldn't ever be any higher than that.

Q: I'm trying to reduce my sugar intake, can I use less than the recommended amount of sugar?

A: No. As we like to say at TKS, the sugar isn't for you, it's for the culture. Kombucha cultures feed on sugar - it is a necessary piece of the fermentation puzzle (the yeast in the culture process the sugar for energy, in turn creating Co2 and alcohol). Lowering the amount of sugar in your brew will only throw off the fermentation process. Remember, with an average 2 week brewing period, most of the sugar has been processed out by the time it is ready to drink. 

Q: Do I have to use refined/granulated sugar?

A: Yes. Traditional kombucha cultures have evolved to feed on granulated white sugar and cannot properly ferment without it. Thick sugars like turbinado, sugar in the raw, and brown sugar are too difficult for the culture to break down and process. Also, always avoid alternative sugars like honey, stevia, etc. as the culture will struggle to thrive. For reference, we use Wholesome Sweeteners Evaporated Cane Juice (Organic Sugar) in our brewing kits. 

Q: I finished brewing my kombucha! How long can it sit in the fridge before it goes bad?

A: You can store kombucha bottled in the fridge for months. Like vinegar, kombucha has a very long shelf life due to the low pH. The shelf life can fluctuate based on various storage variables, but we tend to try and drink up our kombucha within 3 months. However, the fresher your kombucha is, the tastier it will be! So if you want it to always taste fresh, we recommend drinking your kombucha within a month of going into the fridge.

Q: Can I store my culture in the refrigerator?

A: You can store Kombucha cultures in the refrigerator for a short period of time, roughly 2 weeks is all we recommend.  Storing in the refrigerator is a risk - if Kombucha cultures are refrigerated, the yeasts and bacteria go dormant in the cold temperatures and can have a hard time bouncing back to full brewing strength after they have been chilled. Sleepy yeast and bacteria leaves your brew more at risk to develop mold.

If you do refrigerate your culture, store it in a glass jar in at least 1 to 2 cups of starter tea with a lid. The night before you would like to brew again, simply remove it from the refrigerator, place on your countertop and cover with a cotton cloth and rubber band. Allow the culture to return to room temperature over night before brewing the next day. If it has been refrigerated for a period longer than 2 weeks, use the process in the above answer to feed your culture the night before brewing with it. 

Q: My Kombucha tastes great, but it's not very fizzy, what can I do to make it more carbonated?

Carbonation is created when yeast converts sugar into Co2 and alcohol - if you want to increase the C02 (fizz), there are several things you can do to increase the carbonation in both the first and second fermentation.

First, let the first fermentation brew for longer. Allowing your initial brew to go for at least 14 days will strengthen all of the activity in your current brew and create stronger starter tea moving forward (making your future batches better). At the end of your first fermentation, there should be at least a small amount of natural carbonation that has built up. 

If you'd rather only do the initial brew for 9 -14 days but still want some good carbonation... then bottling for a second fermentation is for you!

Try these second fermentation steps to get your kombucha bubbly:

1) Fill your kombucha bottles closer to the top. Leaving no more than a half an inch of space. By reducing the amount of oxygen present in the bottle, more Co2 is dissolved into the Kombucha.

2) Increase the sugar content in your second fermentation. Either add fruit or fruit juice in to each of your bottles (if you've already tried this and it didn't make it more carbonated, try adding 1 tsp sugar to each bottle).

3) Allow the second fermentation to go longer, try 4-6 days. Do note, you will need to start burping the bottles once a day after about 3 days of fermenting to keep them from exploding (it's rare, but it happens). Simply open each bottle slowly to release the Co2 and recap. 

4) Your Second Fermentation should be at room temperature. As soon as you place a bottle in the refrigerator, fermentation, and therefore, Co2 creation, will cease. If you like it bubbly, don't place in the refrigerator until its reached the carbonated level you enjoy.

5) If you are using old Kombucha bottles from the store, try placing a small square of parchment paper underneath the cap to get a tighter seal. Swing top bottles are the best bottle type for building holding carbonation. 

6) Lastly, realize that your brew may never reach the highly carbonated levels of grocery store Kombucha or soda because they add artificial Co2 during bottling. Unfair expectations! 

Q: I found a flavored organic tea that I think will be yummy addition to my Kombucha. Do you recommend using it?

A: The efficacy and safety of using flavored teas totally varies based on the amount of oils in the tea. If you don't mind the possibility of throwing out a batch, then go ahead and try using it! If your culture grows in normally and looks fine, then the tea is good to use. If your culture doesn't grow in or looks kind of sickly, then this tea will not work for brewing.

We are coming out with a line of flavored teas that are specifically made to be safe for your culture-- keep an eye out for them in our shop!

Q: I finished my first brew, and I now have two cultures, should I use the old or the new one for my next brew?

A: You can use both! We recommend keeping anywhere between 1-3 cultures in your brew at a time. Eventually you will want to discard old cultures and use the newest ones. Old cultures are ready to be retired after 10-15 brews, or if it turns a really dark brown and can be ripped apart easily. Oftentimes, your old and new culture will form into one large culture which is great as well. If your cultures continue to grow onto each other, be sure to keep the whole culture under 2 inches thick (height). Simply peel off the oldest layer to accomplish this, or cut in half. It's important not let it get too big (over 2 inches thick) as it will start to inhibit the flow of oxygen to your brew, and process the sugar too quickly, which will throw off the proper yeast/bacteria ratio. 

Q. I have been brewing for a few days and my culture suddenly sank to the bottom of the jar, is that ok?

A. Yes! That is fine, there was likely a fluctuation in temperature and it caused the culture to sink. It can sink, it can float on top or sit in the middle-- it's fermenting all the same. Your culture is still working hard to produce a new culture that will cover the surface of your brew. Evidence of this new culture should appear by Day 7. It can take up to 2 weeks for a new culture to grow in on the top.