Kombucha Fermented on Zante Currants

I’ve previously made kombucha fermented on raisins. This is a minor derivation on that – kombucha fermented on zante currants. (It’s probably worth noting that zante currants actually tiny dried grapes, and are not true currants.) To make this, I added 1/2 cup of zante currants to a 1 qt micro-batch of my usual kombucha.

Kombucha with 1/2 sugar, 1/2 glucose, with hops

I normally make kombucha with regular white sugar (sucrose), and I’ve made a few batches using glucose as the carbon source for the microbes. This time, I used half-sucrose, and half-glucose. Once it was done, I flavored it with hops.

Kombucha-Fermented Apple Juice, Batch 2

Since the last batch seemed like it might have had too little yeast activity and too much bacterial activity, I decided to try adjusting things. When I added chestnut tannins to cider, it seems like it pushed the fermentation towards yeast, but I decided to try a different tactic this time.

Caramel Kombucha

I read the results of few different experiments on the effects of different sugars in the fermentation of beer, and was inspired to make my own caramel use as the sugar source for a batch of kombucha. One of the reasons this appealed to me is that I’ve never followed the conventional advice to dissolve my sugar in my steeped tea as it cools. I’ve avoided this out of a concern that some of the sugar might caramelize, which could have some effect on the flavor of the kombucha (seems somewhat likely) or health of the microbes (seems unlikely).

Date Syrup Kombucha

I was intrigued to see that date sugar is nothing more than dehydrated dates ground into a coarse powder. I wondered what the effects would be from the non-sugar components, so I decided to give it a try. While shopping I noticed that date syrup was a lot less expensive than date sugar, so I decided to use 1/4 cup of that in place of the usual sugar in an otherwise normal 1 quart micro-batch.

Erithritol / Stevia Kombucha

I know many people are wondering about this, because they want to limit their sugar intake and think this may be a way to do it. The big question is whether the yeast and bacteria in kombucha can actually use the erythritol or stevia as a carbon source. Everything I’ve read says that they won’t, but there are yeast and bacteria that will ferment stevia, and I’ve found one reference to a bacteria that will ferment erythritol. The big question is whether any of those yeast or bacteria are in the kombucha culture. I used 1/2 cup of stevia-blend sweetener in place of the usual sugar in a 1 quart micro-batch of my usual kombucha to find out.

Kombucha-Fermented Apple Juice

As a followup to my third batch of kombucha cider, I used a kombucha culture to ferment common inexpensive apple juice. It contained water, apple juice concentrate, and ascorbic acid, and I added a scoby. The starting pH was >4.4.

Molasses Kombucha

I used blackstrap molasses in place of sugar in this 1 quart micro-batch that’s otherwise normal. Unlike white sugar, molasses contains vitamins and minerals, and I’ve seen it mentioned as a potential additive for kombucha and water kefir. A potential risk is that many vitamins and minerals beneficial within specific bounds, but detrimental above those. For example, magnesium and zinc are each needed for yeast to function, but too much zinc can reduce yeast growth while excess magnesium does not.

Kombucha Cider, Batch 3

After 16 days of fermentation, I bottled my third batch of cider. This one was just like the last, except with the addition of 1/4 tsp of powered chestnut tannin. In theory, the tannin should make the cider more interesting (through body and “bite”), though apples are relatively high in tannin already, so it may not have been useful.

Malted Kombucha

I made a 1 quart micro-batch of kombucha, following my usual recipe, except that in place of sugar I used Briess Pilsen omried malt extract (DME). Malt is a particularly interesting sugar source because a kombucha culture should be able to thrive on malt alone. In this case, malt + tea should have provided a surfeit of nutrition. Would this produce similar effects to my double-sugar kombucha?

Lactose Kombucha

Lactose isn’t fermented by normal beer yeast and is added to make it sweeter without increasing alcohol content or carbonation. But some yeast and bacteria can use lactose, and some of the species that can (*) are known to be common in kombucha, so I sweetened a micro-batch of kombucha with it (in a 1:1 replacement for my typical white sugar) to see what would happen.

Kombucha-Fermented Coconut Water

I added scoby to jar of Simple Truth coconut water. This brand appears to have quite a bit less sugar than other brands (even the unsweetened ones), so I wasn’t sure if I would need to add sugar to get it working. I decided to leave it for a week or two, and play it by ear. Most recipes for fermented coconut milk are either CW + water kefir grains, or CW + <your favorite probiotic capsule>, so I hoped CW + scoby will work just fine.

Honey Kombucha

I’ve seen a lot of people write about how honey has antimicrobial properties and it’s bad to use it in kombucha. I decided to put it to the test, and see if I could successfully brew kombucha using only honey as the sugar.

Kombucha-Fermented Red Wine?

Yes, fermenting something that’s already fermented sounds a little crazy, what can I say? Inspired by my success at adding vodka to the normal kombucha fermentation process, and the ongoing batch of kombucha-fermented cider, I decided to see what would happen if I added a kombucha scoby to a bottle of red wine. Rather than a nice continuation of the vodka experiments, I mashed the two together.

Kombucha Fermented On Goji Berries

I’ve taken notes on quite a few different batches of kombucha that aren’t yet documented in a blog post. This is one of those…

A new type of experiment for me. I’ve made hot-water extracts of many different things, including goji berries, but I’ve never added any actual fruit to my gallon fermentation jar.

Maple Syrup Kombucha

I’ve taken notes on quite a few different batches of kombucha that aren’t yet documented in a blog post. This is one of those…

I made a batch of kombucha using maple syrup as the sugar. The maple syrup was made by my late father in law from the trees on his property in southern Illinois.

Glucose Kombucha, Take 2

I’ve taken notes on quite a few different batches of kombucha that aren’t yet documented in a blog post. This is one of those…

I’ve made glucose kombucha before. I made it again in hopes of stopping fermentation before all of the sugar fermented out. I wouldn’t expect it to taste sour at that point (despite a relatively high acidity), but it would probably be rather drinkable while still imparting the usual probiotic benefits to my vinegar-phobic family. If nothing else, it could be used to make lemonade, sweet tea, etc.

Kombucha Cider, Batch 2

My first batch of kombucha-fermented cider turned out pretty well, to the point of sparking interest from my kids, so I quickly made another batch. This was largely the same as the first time around, this time remembering to have the heat on the whole time (as the first batch was intended). There was also a small procedural difference: since the first batch ended up over-fermented, I was careful to check pH and flavor every two days.

Piloncillo Kombucha

I’ve taken notes on quite a few different batches of kombucha that aren’t yet documented in a blog post. This is one of those…

I picked up 4 cones of piloncillo from Meijer, and grated three of them to make ~1 cup of sugar. Piloncillo is made by putting sugarcane juice into a mold, and letting the moisture evaporate. It’s a lot like brown sugar used to be, before they made brown sugar by mixing a little molasses into plain white sugar.

Kombucha-Fermented Apple Cider

I’m fond of cider, and I was curious what would happen if the “usual” cider fermentation process was augmented with a kombucha culture. I dropped a scoby into unpreserved apple cider to find out. On one hand, it seemed promising, since hard cider (fermented “naturally” or otherwise) tends to happen readily and has tasty results. On the other hand, I wasn’t adding anything with acid or alcohol to help ensure that the kombucha culture dominated the process. It would be possible to end with something disgusting, or even toxic.

Xylitol Kombucha

This 1 quart experiment was started early March, and ran for 6 weeks. At the time I wrote:

This is a quart of “normal” kombucha except that the white sugar has been replaced with xylitol. I’ve read that xylitol doesn’t work in kombucha, so this has the same expected minimal fermentation as the sugar-free kombucha, except sweetened by all of the starting unfermentable xylitol. In other words, I may end up with plain sweet tea. However, there are a few yeast or bacteria that can use the xylitol, and perhaps some are in my culture. We’ll  see!

Half-Sugar Kombucha

When writing up my double-sugar kombucha, I mentioned that I would follow with a batch of kombucha with half the sugar. This is it.

Sugar-Free Kombucha

No, this isn’t a euphemism for artificially-sweetened Kombucha. It’s an experiment to confirm that it doesn’t work to brew kombucha without a carbon source (sugar). This was started last month, but I’m just now getting around to posting about it. This batch was simply, tea + kombucha culture.

Double-Sugar Kombucha

Gluconacetobacter xylinum (formerly named Acetobacter xylinum) has been established as a defining microbe in kombucha. It’s also been demonstrated that in a high-glucose environment, Ga. xylinum produces less cellulose (scoby) and more gluconic acid. This prompted me to make a batch of kombucha with twice the usual sugar (2 cups/gallon).

Agave Kombucha

Apparently, agave syrup is 60-90% fructose. I used C&H Organic Blue Agave, but I don’t know what the fructose content was. I’ve read that fructose becomes acetic acid while glucose becomes gluconic acid.  Since one of my goals is to produce a probiotic drink that doesn’t taste like vinegar, I want to better understand the process by which acetic acid is formed, and see if I can influence it. Thus, I made a batch of agave kombucha expecting it to taste very vinegary. It didn’t.

Small-Scale Kombucha Experiments

Below is the result of two previous experiments, and two new ones. Since I only get 2-3 cups of finished product, I’m not planning to add any additional flavoring when I bottle.

Basic Kombucha Science

As I understand it, this is the chemistry (biology?) involved with basic kombucha, oversimplified. I’m not an expert, but I’m presenting this as my effort to work though the process of what is needed, why it is needed, and how it ends up producing something desirable.

Brown Rice Kombucha

The “sugar post”. I should really have more references, even it’s just a URL where I read about different things, but I wasn’t taking notes. Sorry.

Virtually all kombucha recipes call for sucrose (table sugar), though some call for brown sugar, sucanat, or other things that are still basically sucrose. Some even call for maple syrup, honey, molasses, etc. Chemically, sucrose is almost a 50/50 split between fructose and glucose, and the same is pretty much true for most natural sweeteners, including more exotic things like date sugar or coconut sugar (though not stevia, which is magically sweet without sugar). This means that, chemically, the difference these things will make in the final brewed kombucha will primarily come from whatever additional things (impurities) happen to be flavoring the sugar you use.