Brew your own Kombucha

In this lecture we will discuss:

• Ingredients required for brewing
• Kombucha brewing & storage supplies

Ingredients

•  ¾ to 1 cup Sugar; I use fair trade organic cane sugar- it is the easiest for scoby to breakdown and I’ve found that is makes the best kombucha. The sugar and caffeine are food for the Kombucha culture and most of it is used up by the mother in the fermentation process. This means that you will only consume a very small amount of it in the actual tea.
•  6-8 caffeinated tea bags, I use organic green or black tea
• 1 cup starter liquid; you can use liquid left over from your previous batch of kombucha.
• 8 - 15 cups boiled/purified water
• Kombucha scoby
• Fresh fruit, ginger or fruit juice for flavoring
• Apple cider vinegar and natural soap for cleaning

Storage supplies

• A clean pot for boiling water and combining sugar and tea
• Coffee filters or a tightly woven cheese cloth to cover the mouths of the jars
• Rubber band to secure the cheese cloth or coffee filter
• Glass gallon jars
• Glass growlers or other tightly sealing bottle/jar

Covered in this lesson: How to grow your own scoby from scratch

However, a quicker and easier option is to buy a scoby from a reputable source. 

In this lesson we will discuss: 

• What is first stage fermentation?
• How to clean your supplies before brewing
• How to brew your first batch of tea
• How to add your freshly brewed sweetened tea to your culture

First Stage Fermentation

This is when the cultures digests the caffeinated tea and sugar to ferment, producing organic acids, vitamins, amino acids and enzymes as by products.  Every week I make a new batch of tea and decant the current batch. The first batch you make with the mother you may need to wait a little more than a week, but you can sample some of the liquid, if it’s very sweet let it ferment longer but if it has a very strong vinegar taste it may have fermented too long. There is nothing wrong with letting it ferment longer, it is really just a matter of taste preference. 

Clean your supplies

Ensure all jars are clean and sanitized before placing your scoby in them. See the attached resource "General Cleaning Procedure" for the detailed cleaning method. I clean my main vessel once every two to four months just so that balance of yeast doesn't get out of wack (you will see a lot of debris at the bottom of the jar), but it's up to you how often you clean.  

Adding the sweetened tea to your culture

Once the tea has cooled, pour it into the kombucha jar with the mother and starter liquid (leftover from the last batch). Careful not to disturb the mother too much when you do this. You can get someone to hold the jar on an angle so that I can pour the tea in very slowly without shaking up the mother. If the scoby sinks don’t worry. Cover with a thick cheese cloth or coffee filter and secure with a rubber band. Place the jar in a dry, dark and warm place where it won’t be disturbed and let it sit for ~7days. The longer you let it sit the more acidic it will get, less time will make it sweeter. It’s personal preference. 

Begin the second and final part of fermentation before your tea is ready to drink.  In this lesson we discuss:

• What is second stage fermentation?
• How to pour off your kombucha after first stage fermentation
• Flavouring your kombucha
• Ways to drink & enjoy

After it is poured from the main reservoir, the yeast will continue to ferment the sugar in the tea, producing carbonation, this is known as second stage fermentation. This is an excellent time to infuse your kombucha with any additional flavors. Growlers work best for this step, they seal tight enough while the rubber stopper still lets a little air out to avoid explosions.

Decanting your kombucha after first stage fermentation is complete

After approximately one week your kombucha should be ready for second stage fermentation. Do a taste test and if it tastes ready you can decant it. Do this over the sink: 

• Gently pour the kombucha from your main reservoir into the growlers, with flavoring ingredients already added. 
• Fill the bottles almost to the top, leaving only a few cm. Do this slowly as not to disrupt the scoby too much. 
• Continue filling bottles until there are only a few inches (~1-3 cups) left with the scoby in the main vessel. 
• Seal your bottles and store in a warm and dark place for ~2 to 5 days, after which you can move to the refrigerator.

Brew a new batch of tea and add it to the existing starter liquid and scoby. For every new batch you make you will need to have some starter liquid left in with the mother (~1-3cups).

Flavoring 

Flavoring is optional, you can skip this step if you’d like and just decant the kombucha for second stage fermentation without adding any extra ingredients. You can use fresh fruit, fruit/juice concentrates, ginger, food grade essential oils and syrup to flavor. 

Ways to drink and enjoy 

Although some argue that this is unnecessary, I like to dilute my kombucha with carbonated water. After second stage fermentation is complete I drink my kombucha by adding half kombucha to a glass and half carbonated water. I also add ice to my booch, I find it amps up the carbonation a bit more. Use as a healthy substitute for soda or alcohol, drink in the morning on an empty stomach for maximum benefit and share your kombucha with friends/family!

In this lesson we discuss:

• How to clean jars
• How to separate scobys as they multiply
• Storage of extra scobys aka scoby hotels

Cleaning

You will want to clean your main vessel, the one that houses the “mother”, once every few months just so that the yeast/bacteria balance doesn’t get out of wack. You might notice a lot of debris at the bottom of your jar (that’s yeast!), this is ok but when it starts to build up you may want to clean so that the culture balance doesn’t get out of wack. Always clean your hands very well before touching your scoby!!

Separating Scobys

As the culture matures you may notice that your scoby starts to thicken and multiple, forming multiple layers usually at the top of the jar with each brew. With clean hands, you can gently pull the layers apart and store extra scobys in a scoby hotel. If the scobys don’t easily separate, you can use a stainless steal knife or pair of scissors to cut the scobys apart.

 Storage of extra scobys

Over time you will start to accumulate scobys as the culture grows and multiples. It is a good idea to save the extras so that you have backups if your main scoby gets contaminated or molds. You can create a scoby hotel by storing all the extra scobys together in a galloon jar. They can often exist in the jar for months before you need to feed or clean to remove excess yeast and keep the bacteria:yeast ratio in check.The liquid in the scoby hotel is great for using as starter liquid in any new culture or to give your current culture a boost.

Do not store extra scobys in the refrigerator! This can kill them or cause them to mold!

It is important to be able to recognize when something is off with your culture. With every batch examine your scoby. Here are some important things to be aware of:

• Mold: it is actually quite rare for the kombucha culture to mold, but you should still observe the scoby for any signs of mold. Discoloration is not mold, mold will usually look fuzzy and will often grow on the top of the scoby. That said, if you suspect mold discard the batch immediately, compost the scoby and clean the jar very well. You will have to start a fresh culture (hopefully you’ve been saving your scobys!)
• Fruit Fly’s: Fruit fly’s are nasty little guys! They can get in through the holes of cheesecloth and lay eggs in the scoby. I have had two cases of fruit fly contamination and had to throw out two cultures. The best way to avoid this I have found is to use coffee filters. I usually double up with two filters. It still lets enough air flow in while keeping the bugs out.
• Chlorine: It is best to use purified or filtered water for your kombucha. The chlorine in tap water can kill some of the healthy bacteria in the culture and throw off the balance of the culture. I have found the boiling tap water for ~10mins before adding tea works and I haven’t had any issues.
• Bumpy holey scoby: This is totally normal and is caused by gaseous byproducts of fermentation. As the yeast and bacteria ferment the tea and sugar, carbon dioxide is produced as a byproduct; this is what makes the tea fizzy. The scoby in the jar creates a seal that traps the gases inside.
• Discoloration: It is normal for the scoby to darken as it gets more mature. I have seen a range of colours in my scobys from white to brown. As long as the culture looks healthy, aka no mold, and makes yummy tea you are fine to keep using it.

Care basics:

•  Use glass for your main brewing vessel, extra scoby storage and for second stage fermentation.
• Store kombucha in a dark, warm place where it won’t be disturbed. The ideal temperature to keep the yeast bacteria balance in check is ~20-30°C
• Allow for airflow in your main vessel and any other jars that hold scobys.
• Do not use antibacterial soap to clean any of the jars. Vinegar and water work best however I have had success using a gentle natural soap and rinsing very well after.
• Never store scobys in the refrigerator
• Wash your hands very well every time you handle the scoby

In this lecture I will explain some common causes of a culture that is taking a long time to ferment and scobys are not growing/multiplying. It can be hard to diagnose what is wrong with a culture without seeing it and observing how the brewer is brewing. However some possible reasons for this are as follows:

• Scoby thickness; a thin scoby takes longer to ferment
• Too much sugar to the tea. When there is excess sugar it can actually cause the yeast in the culture to become dormant, which will slow or halt the fermentation process
• Temperature; too low and too high can cause issues
• Not enough starter liquid
•  Poor airflow. The bacteria in the kombucha culture require oxygen in order to live and ferment the tea. This is why it is important to cover your jars with a breathable filter to allow adequate airflow to the culture
• Scoby was refrigerated prior to brewing – never store scobys in the fridge
• Antibacterial soap was used for cleaning and not properly rinsed
• Wrong sugar type used, as mentioned stevia cannot be broken down by the culture and should not be used
• Wrong tea used. Avoid using herbal teas or teas that have oils and additives in them

This is when you get to become creative! You can experiment with any flavors but I've included some of my favorites in this lecture and the attached PDF. 

Remember, always wash fresh fruit very well before cutting. I suggest opening bottles over the sink as sometimes the added sugars in the fruit cause a lot of gas build up.

In this lesson I will explain some of the science behind a Kombucha culture, with a specific focus on Microbiology.