Simple Brewing and Bottling Instructions

These are my simple brewing instructions that I provided at my demo earlier this year for the Urban Homesteaders' League Market Stand. In addition, I've included my simple bottling instructions. More detailed brewing instructions can be found here, and more detailed bottling instructions are here. In addition, this is a link to a post where I list/link to several other kombucha recipes for more perspective and additional information. There is no recipe that's "right." Every brewer has his or her own style and favorite recipe, so adapt the recipe to what works for you!

My next Kombucha Brewing Demo will be sometime in December. Stay tuned for details, and happy brewing!

BREWING DIRECTIONS

Note: It is recommended to clean the equipment with white distilled vinegar, because of soap’s antibacterial properties, which may harm the bacteria in the SCOBY.

Materials

• 1 kombucha culture (also known as a kombucha mother or a SCOBY)
• 2 black or green tea bags (or around 1 tsp. loose leaf tea) per quart water
• ¼ cup (50 g) sugar per quart water
• ½ cup (4 fl. oz) starter tea per quart water
• Water
• 1 glass jar
• 1 pot to boil the water (such as stainless steel, don’t use aluminum)
• 1 clean cloth or paper towel
• 1 rubber band

Directions

1. Boil the water.

2. Add the tea and allow it to steep for 15 minutes.

3. Remove the tea bags/tea leaves.

4. Add the sugar and stir until it all dissolves.

5. Let the sweet tea solution cool down to room temperature (hot temperatures can kill the SCOBY).

6. Pour the sweet tea solution into the brewing container.

7. Add the starter tea into the brewing container and stir it so that it’s evenly distributed throughout the solution.

8. Add the SCOBY that is also at room temperature (it’s ok if it floats or sinks).

9. Cover the container with the clean cloth and secure it with a rubber band.

10. Put your brewing vessel in a quiet, undisturbed spot.

a. With each brewing cycle, a new baby mushroom typically forms.

b. SCOBYs like warm temperatures and the brewing vessel shouldn’t be moved during the fermentation process, because movement will disrupt the formation of the new SCOBY.

c. SCOBYs prefer warm temperatures and brewing between 75-85 F is ideal, 68-85 F is ok.

11. Leave the tea to ferment for 6-14 days (kombucha ferments more quickly in warmer temperatures, so the 6-14 days is just a guideline).

12. Your kombucha tea is done! (Signs include an apple cider vinegar aroma or taste. Taste is the best indicator; it should taste similar to a slighty fizzy version of apple cider vinegar).

13. Set aside a SCOBY and some kombucha as starter tea for your next brew.

14. Drink your kombucha tea as is and store the extra in the fridge, or consider letting your kombucha undergo a second fermentation in the bottling process.

Tip: When first learning how to brew, it is recommended to brew smaller batches (1-2 quarts). Once you get the hang of it and the kombucha mother has produced new SCOBYs, you can brew larger quantities.

Sources:

• http://www.happyherbalist.com/libraryandresearch.aspx
• http://www.kombu.de/anleit-e.htm
• http://www.kombuchafuel.com
  

BOTTLING DIRECTIONS

Materials

• Kombucha
• Bottles and caps
• Bottle capper (if you are bottling your kombucha in beer bottles)
• Optional: small pieces of cut up fruit, ginger, herbs, or jams to add flavors to your kombucha. The possibilities are endless!

Directions

1. Optional: Add some flavors to your brew by adding little pieces of cut up fruit, ginger, herbs, or jam to your bottles. Smaller pieces are better because they give the yeast more surface area to act on.
2. Fill your bottle(s).
1. I typically leave around 1.5 inches of headroom for a 12 oz beer bottle.
3. Cap your bottle(s).
4. Leave your bottle(s) out at room temperature for 1-2 days, or for week(s).
5. Fill your bottle(s).
1. The kombucha is undergoing a secondary fermentation, which can produce more fizz in the kombucha. The secondary fermentation is also a good opportunity to add different flavors to your brew.
2. Kombucha ferments more quickly at higher temperatures.
3. Typically when I have a batch I try one bottle after a few days, and decide whether the rest of the bottles are ready to refrigerate or require more time to ferment.
4. *PLEASE NOTE* if you leave your bottles out for too long, they may explode due to the buildup of carbon dioxide.
6. Refrigerate the kombucha.
1. Refrigerating the kombucha will cause the yeast and bacteria to go dormant. Fermentation isn't completely stopped, but is slowed significantly.
7. Enjoy and drink your kombucha!

Where to shop: The Modern Homebrew Emporium is great for brewing supplies of any kind. Location: 2304 Massachusetts Ave., Cambridge, MA 02140, T: (614) 498-0400.

Bottling and Headroom (Updated July 12, 2010)

***For the update please scroll down to the bottom of this post***

After several readers inquired about leaving headroom when bottling, I felt obligated to experiment.

I had always learned to fill the kombucha all the way to the top when bottling for a secondary fermentation. This stops the activity of the bacteria because of the exclusion of oxygen, while the yeast can continue to ferment the sugars to create CO2 and an effervescent drink, because yeasts can function with or without oxygen (1).

After being prompted to do some experimenting on my own, I left around an inch of headroom in several kombucha bottles for a secondary fermentation. I left the bottles out for a few days, and then I refrigerated them. I didn't open the bottles right away because I already had some kombucha bottles open, but I pulled one out from the refrigerator a week or so later and found that the kombucha bottled with around an inch of headroom was more fizzy than a good number of my previous batches!

Bottling with Headroom
Photo courtesy of Haven Sarah Ripley Daniels

Although Happy Herbalist mentions to fill the kombucha to the top of the bottles in their Brewing Guide (look under "Bottling"), on their Bottling Tips page there is a section "Choosing to leave an airspace." According to their Bottling Tips page, if you leave oxygen and airspace in the bottle and if the temperatures are between 70-85 degrees F, the bacteria will continue to remain active and the kombucha will continue to sour, which makes sense because the bacteria require oxygen.

Meanwhile, the yeasts can function with or without oxygen. However, according to Happy Herbalist, yeasts only form carbon dioxide and fizz when oxygen is present (2). "Carbon dioxide suffocates/diminishes the bacteria, but produce[s] the fizz and sparkling brew. Without oxygen the yeast produce more alcohol...The yeast may be active in temperatures as low as 40F (5C) with or without oxygen" (2). In other words, if you leave headspace when bottling, the yeasts can create more carbon dioxide and fizz because of the oxygen present in the airspace. But if there is no airspace, the ability of the yeasts to produce an effervescent drink is limited because of the limited availability of oxygen.

Unfortunately, I was perfectly happy with this explanation until I returned to this formula from my previous post, Kombucha + Fizz, and could not find oxygen needed in the equation for the yeasts to form carbon dioxide:

The yeasts convert sugar to alcohol + carbon dioxide (3, p. 40)

C6H1206 -> 2C2H5OH + 2CO2
sugar -> alcohol + carbon dioxide

Thus, I am somewhat still confused about the exact relationship between the yeasts, oxygen, carbon dioxide, and kombucha fizz. Perhaps the presence of oxygen helps to encourage the yeasts to form more carbon dioxide and fizz, but its presence is not necessary?

Something to note is that kombucha that is bottled all the way to the top will taste different than kombucha that is bottled with airspace, such as in the amount of fizz produced and in others ways as well, such as the acidity of the drink.

I have not found much information on the recomended amount of airspace if you decide to bottle kombucha this way. However, beer brewers tend to leave 1-2 inches of headspace in their bottles according to this thread. Again, experimentation is key, and do whatever you prefer according to personal preference and taste!

As always, I am continuing to learn more about kombucha day by day, and I hope to share that information. If you have any more information or tips on the bottling process and kombucha fizz, please send the information my way or leave a comment!

All my posts related to bottling can be found here.

References
1. http://www.happyherbalist.com/brewing_kombucha.htm
2. http://www.happyherbalist.com/bottlingtips.aspx
3. Frank, Gunther W. Kombucha - Healthy beverage and natural remedy from the Far East. 4th ed. Austria: Wilhelm Ennsthaler, 1994.

***Update July 12, 2010***

I was able to get to talk to a brewer who brews beer and kombucha. Here is what I learned:

• Confirmation that headroom helps prevent the bottle from exploding from the buildup of carbon dioxide.
• You can still increase the fizz in your brew whether or not you leave headroom in your bottle.
• You won't lose fizz by leaving headspace in the bottle.
• You lose more fizz the more you transfer the kombucha from container to container. You can actually decarbonate your brew by transferring your kombucha from container to container.

In this article from Happy Herbalist, it states that aerobic and anaerobic yeasts in kombucha help to produce carbonation, and that the production of more carbonation than alcohol by both types of yeast is favored when oxygen is present, which is in line with the other Happy Herbalist information (that I am conflicted about) that I provided above.

Part of the reason why there doesn't seem to be a clear answer to the question about whether it is better or not to leave headroom to create more fizz, is because kombucha ferments and SCOBYs contain different strains of bacteria and yeasts and in different proportions. Wild and airborne bacteria and yeasts, which differ according to the location and environment, add even more variation to the mix. Here is one Analysis of a Kombucha Ferment by Happy Herbalist as an example for what may be in your brew.

I personally prefer to bottle with headroom at the moment. But it is up to you, and based on your experiences, to decide whether or not you want to leave headroom in your bottles. I recommend experimenting with both. If anyone wants to share their experiences with bottling, please do so!

Kombucha + Fizz (Updated May 27, 2010)

Yes, kombucha can be fizzy.

I've been receiving numerous questions about fizz, so here is what I understand thus far on the matter!

To begin, fizz does not indicate the health of your SCOBY or your ferment. Fizz is more a matter of personal preference, and may indicate the balance of yeasts and bacteria in your brew (1, 2).

For the scientific side on the matter, here are the chemical reactions that occur during kombucha fermentation (3, p. 40):

The yeasts convert sugar to alcohol + carbon dioxide.

C6H1206 -> 2C2H5OH + 2CO2
sugar -> alcohol + carbon dioxide

The bacteria convert the alcohol to organic acids, such as acetic acid, and water.

C2H5OH + O2 -> CH3COOH + H20
alcohol + oxygen -> acetic acid + water

The CO2 (a gas) that forms reacts with the water in the tea to produce carbonic acid (think of carbonic acid as dissolved CO2). Carbonic acid is a weak acid that readily decomposes back into water and carbon dioxide. When the carbon dioxide bubbles out of the water, you get fizz (4).

CO2 + H2O -> H2CO3
carbon dioxide + water -> carbonic acid

Carbonation and the primary fermentation:
As the new kombucha mushroom forms at the surface during fermentation, the ability for the carbon dioxide to escape decreases, helping to create some of kombucha's natural fizz. The more quickly and the more thick your mushroom forms, the less the CO2 will be able to escape, which can increase the carbonation of your drink (3, p. 33, and 5).

A lower fizz may indicate a lower ratio of yeast to bacteria in your culture. The ratio of yeasts in your brew may be increased by (1):

• Using the bottom SCOBY from your previous batch
• Using more of the kombucha at the bottom of your brew, which tends to be more cloudy/yeasty, for your starter tea.

Carbonation and the second fermentation:

• Fizz can be significantly increased by bottling. My posts related to bottling can be found here.
  
• Consider experimenting with leaving and not leaving airspace. Read my post Bottling and Headroom.
  
• Adding flavors (such as jams, citrus peels, ginger, etc.) during the bottling process can also help to create more fizz. (Similar to adding a primer in beer making).
  
• Beer bottles, which have a very tight seal, are ideal for creating fizz in kombucha. In my experience, when I've used resealable bottles (such as GT's or Katalyst kombucha bottles), I've lost more fizz.
• -The longer you leave your bottles out for a secondary fermentation, the more carbonation will build up. HOWEVER, if you leave your bottles out for too long, you run the risk of them exploding! Some people recommend 1-2 days for a secondary fermentation, others 3-4 days, and some recommend even longer. It all depends on various factors, including the sugar content of your kombucha and the temperature (higher temperatures = faster fermentation).
  -My advice: If you're fermenting a batch, try a bottle after 1 or 2 days (more or less days depending on previous experiences, etc.). Then decide whether your other bottles are ready to refrigerate, or if they could use some more time fermenting.

Some more reading:

• Kombucha Balance on No fizz, Too much fizz, Increasing the ratio of yeasts, and Increasing carbonation
  
• getkombucha: The Fizz Factor #1
• A great thread that discusses fizziness and beverages
  
• Although there is limited information on kombucha and fizz, there is extensive information about carbonation and beer making on the web. Although beer and kombucha are clearly different drinks, they are similar in that they are both fermented beverages. Perhaps looking up beer carbonation will provide more clues as to factors that affect kombucha fizz? Try here and here for starters.

Happy brewing!

Sources:
1. http://users.bestweb.net/~om/kombucha_balance
2. http://www.getkombucha.com/spreisfifa1.html
3. Frank, Gunther W. Kombucha - Healthy beverage and natural remedy from the Far East. 4th ed. Austria: Wilhelm Ennsthaler, 1994.
4. http://uk.answers.yahoo.com/question/index?qid=1006051206579
5. http://kombuchakamp.blogspot.com/2009/04/fizzy-brew.html

Kombucha Bottling 101 (Updated May 27, 2010)

What to do when you are done brewing your kombucha? One thing you can do is bottle your brew.

Why bottle?


Bottling, or a secondary fermentation, allows the yeast to feed on more of the sugar in your kombucha tea. This creates CO2, decreases the amount of sugar in your kombucha, and also makes your drink more carbonated and fizzy, which many people enjoy.

Here are some things to think about when choosing your bottle:
Good:

1. Glass bottles with narrow necks are the most common way to store fermented beverages.
   -old beer bottles* (their tight seals are ideal to create more fizz)
   -EZ Cap (Flip-Top) Beer Bottles
   -wine bottles (nice as a gift or if you're sharing!)
   -etc.

It's your choice:

1. Old kombucha bottles-Pro:
   -GT's now sells kombucha with plastic caps! Many kombucha brands now sell kombucha in reusable bottles.-Con:-In my experience, they sometimes leak, and air can escape more easily as opposed to beer bottles (air leakage can lead to decreased fizz).-If they came with metal caps (ex. the GT ones), the caps usually oxidize/rust easily
   
   
   GT's old metal caps


2. Old plastic bottles
   
   -Pros:
   -The plastic material allows for expansion (decreasing the chance of your bottle exploding).
   -The plastic bottles become hard after a couple of days, signaling that the yeast have consumed most of the sugars in the kombucha and that you are ready to refrigerate it.
   -Cons:
   -Plastics aren't good for the environment.
   -Re-using old plastic bottles could expose you to chemicals. (Especially because Kombucha Tea is acidic!)
   -Note:
   -Some people choose to do an initial secondary ferementation in plastic bottles and then transfer the kombucha into glass bottles for long-term storage. More information on this in the Two Stage Bottling Technique at Kombucha Balance.
   -My recommendation:
   -I don't use plastic bottles for my kombucha, but if you do, please re-use a plastic bottle only once!

DIRECTIONS

1. Optional: Add some flavors to your brew! Put in little pieces of cut up fruit, raisins, goji berries, etc. to your bottle, to add some zing and health benefits to your kombucha! They will provide some more sugars for the yeast to feed on, adding flavors and creating an additional fermentation. It's generally recommended not to add too much biological matter. And the smaller the pieces are, the more surface area that the yeast can act on.What also works well:
   -Citrus fruit peels (ex. grapefruit, lemon, lime, orange)
   -Fresh ginger
   -Jams/jellies/preserves
   Tip:
-If you are using raisins or dried fruit to flavor your kombucha, cut them up first!


2. Fill your bottle(s).-It is up to you on whether or not you would like to leave headroom. For more info, read my post Bottling and Headroom.


3. Cap your bottle(s).
   


4. Leave your bottle(s) out at room temperature for 1-2 days, 4-5 days, or longer.-Personally, I've been doing 4 days, but the time will vary depending on the brew/brewing conditions (ex. the temperature of the room).
   -*PLEASE* do not leave your bottles out for too long. Otherwise, too much CO2 may build up in your bottle, causing it to explode!


5. Refrigerate your kombucha!-If you bottled your kombucha in plastic bottles, the bottles should feel hard when it's ready to refrigerate them.
   -Refrigerating your kombucha will cause the yeast and bacteria to go dormant. Fermentation isn't completely stopped, but is slowed significantly.


6. Enjoy and drink your kombucha! Some people recommend dating your batches, but I always finish drinking my kombucha before the next batch comes around! :)

Note: Like soda, once opened, kombucha goes flat.

*A few comments about beer bottles*:

-If you drink beer, this is a great way to use up old bottles!
-They are easy to get for free. You can even get used ones for free (or cheaply) from restaurants, bars, etc.
-If you feel uncomfortable using old ones, you can buy new beer bottles at your local brewing store, although this is the more expensive route.
-Note- clean them well first!!! Go to your local homebrewing store and get a brush to scrub them out a bit. Then boil them, put them in the dishwasher, use Iodophor, or do whatever it is that will ensure removal of any hiding bacteria/places where bacteria can grow!-To cap your bottles, buying bottle caps are relatively cheap. I got a half pound of caps for only around $3-4 at the Modern Homebrew Emporium in Cambridge. And at only $14, the Red Baron Beer Bottle Capper is a good investment. Find it at your local brewing store or online.
-The one downside- I have to admit that going through bottle caps is not the best for the environment. If this is a concern for you, the EZ Cap (Flip-Top) beer bottles, which are refillable, may be the way to go.

Broken Glass

As I was washing the dishes one day, I heard a slight crack. I looked around the kitchen but didn't notice anything...but soon the smell of kombucha filled the room. Uh-oh.







It turns out, a bottle of my kombucha had exploded- as a kind reminder not to leave your kombucha bottles out for too long for a second fermentation.






I have been fortunate to have never had a bottle of kombucha explode on me before this day, and after brewing kombucha for over a year, I guess it was about time.

Luckily, the explosion was a lot less dramatic than it could have been. When I first began bottling kombucha, I had been nervous about shards of glass ending up on on my wall.

Tips to avoid kombucha bottle explosions:

-As mentioned in my previous post, Kombucha + Fizz:

• Beer bottles with their narrow necks and tight caps are ideal for creating fizz, and the longer you leave your bottles out for a secondary fermentation, the more fizz will build up. HOWEVER, if you leave your bottles out for too long, and especially with such tight seals, you run the risk of them exploding. Some people recommend 1-2 days for a secondary fermentation, others 3-4 days, and some recommend even longer. It all depends on various factors, such as temperature (higher temperatures = faster fermentation).
  
• My advice: If you're fermenting a batch, try a bottle after 1 or 2 days (more or less days depending on previous experiences, etc.). Then decide whether your other bottles are ready to refrigerate, or if they could use some more time fermenting.
  
• If you can hear your kombucha bottles at room temperature fizzing, refrigerate it!!
  

**Please note that this graph is not to scale whatsoever, and was merely created in order to illustrate a concept.**

***The longer you leave your kombucha bottles out for a second fermentation, the more fizzy your kombucha, but the more risk you will have of your bottles exploding. Experimentation and practice are key!***

-Read this discussion thread on bottling technique from some fellow kombucha fermenters.

• According to this thread, flip-top beer bottles can be a good option, because the rubber seal releases some of the pressure that may cause your bottle to explode.

Adding to my list of broken kombucha bottles includes one instance when my refrigerator somehow got to freezing temperatures, causing the kombucha to freeze and expand (when water freezes into ice, the volume expands as the molecules form a crystal lattice), causing another kombucha bottle to break.





At the time I decided to take an artistic approach to the situation, resulting in this photo:

Kombuch-sicle, anyone?

Home-brewing (and in fact, brewing in general) is never perfect. Accidents happen, but they are all part of learning how to brew and how to perfect your technique, and make your home-brewed kombucha that much more worthwhile. What interesting kombucha experiences have you had?