Fermented food

No kit required! How to make kombucha with natural bacteria

2022年1月10日

The person who writes this blog

オトコ中村
Name: otokonakamura
Lives in Kyoto, Japan.
40s
I hope everyone will be healthy and happy through cooking.
I'm muttering various things such as updated information on Twitter.
See her profile page for more information.

No kit required! How to make kombucha with natural bacteria

In Japan, the only way to make kombucha is to buy a starter kit.
However, I found a way to grow and make natural kombucha at home.

【table of contents】
1. Kombucha is a healthy drink
2. Kombucha bacteria are needed to make kombucha
3. I will explain about the bacteria of kombucha
4. Bacterial characteristics of kombucha
5. Strategy to make natural kombucha
6. Experiment with apples (September 5, 2021)
6−1. 6 days after preparation (September 11, 2021)
6−2. Two more days have passed (8 days after preparation) September 13, 2021
6−3. 3 more days (11 days after preparation) September 16, 2021
7. Experiment with raisins (September 16, 2021)
7−1. Five days have passed since the raisins were added (September 21, 2021)
7−2. 5 more days (10 days with raisins) September 26, 2021
8. Looking back on apples and raisins
9. Prepare persimmons and marvel-of-Peru (September 26, 2021)
9−1. 5 days later (October 1, 2021)
9−2. 4 more days (9 days after preparation) October 5, 2021
10. This preparation with marvel-of-Peru (October 5, 2021)
10−1. 8 days after the main preparation (October 13, 2021)
10−2. 15 days after the main preparation (October 20, 2021)
11. Drink natural kombucha
12. summary
13. Explained in the video

Kombucha is a healthy drink


Kombucha is a drink made by fermenting black tea, and fermentation forms a film called scobby in black tea.
It is also called black tea mushroom in Japan because its film looks like mushrooms.

If you drink this, you can expect a diet effect and a detox effect.
For that reason, celebrities from overseas are drinking it, and it has gradually become a hot topic in Japan.

I've been drinking this for about 3 months and I'm feeling better.
About two weeks after I started drinking, I felt a change in my poop.

Kombucha bacteria are needed to make kombucha

↑This is the starter kit.
It cost 2880 yen on Amazon in Japan (as of June 2021).
Isn't it a little expensive?

However, if you want to make kombucha in Japan, you only know how to make it using that kit.
So I have to buy a kit.

Even if you say that you can expect a health effect, you do not know how much it is until you actually try it, and the effect is different for each person.
I drank for 3 months and my stomach got better, but until I actually drank it, I would say clearly ...

I thought it might be a scary fermented drink.

It is a high hurdle to pay 2880 yen to make that scary fermented beverage.
I love fermented foods, and I bought it because I can use it as a blog post.
The hurdle is high for ordinary people.

So, I was wondering if there was a way to make kombucha without using a kit, so I searched for various things.
Kombucha bacteria are bacteria that exist in nature, so if you find them, you can make them.

And the result of the experiment ...


I discovered that Kombucha bacteria are attached to Marvel-of-peru.

Let's take a look at the process of successfully making kombucha in Marvel-of-peru.

I will explain about the bacteria of kombucha

Kombucha is a drink made by fermenting kombucha bacteria.
In order to ferment kombucha bacteria, it is better to know about kombucha bacteria. So, let's talk about kombucha bacteria.

The term kombucha bacterium is just what I call it.
Kombucha bacteria are a member of acetic acid bacteria and belong to the genus Gluconacetobacter.

【Official name of kombucha bacteria】
Gluconacetobacter kombuchae

Is the official name.

There are many other members of the genus Acetobacter.

【Bacteria of the genus Acetobacter】
Gluconacetobacter kombuchae
Gluconacetobacter swingsii
Gluconacetobacter xylinus
Gluconacetobacter europaeus
Gluconacetobacter maltaceti

These are all kombucha bacteria.

You don't have to remember the name of such a bacterium.
These are collectively called kombucha bacteria.

And, of course, kombucha bacteria are bacteria that exist in nature.

Kombucha bacteria are also a member of acetic acid bacteria.
Acetobacter is a bacterium that makes vinegar.

By the way, the acetic acid bacteria that make vinegar

【Acetobacter that makes vinegar】
Acetobacter aceti
Acetobacter pasteurianus
Acetobacter oxidants
Acetobacter rancens

We have others, too.

And so on.
You don't have to remember the name either.

I write videos and blog posts about homemade vinegar.
There, I will introduce how to make vinegar using acetic acid bacteria.

Since acetic acid bacteria and kombucha bacteria that make vinegar are friends, the growth conditions are very similar.
That's why the experience of making vinegar comes to life.

Bacterial characteristics of kombucha

【Characteristics of kombucha】
Kombucha bacteria like black tea (green tea is OK)
Kombucha bacteria feed on sugar
Kombucha bacteria are strong against acid
Kombucha bacteria need oxygen
Kombucha bacteria Is active around 30 ℃

It is a characteristic of kombucha bacteria.
In Japan, it's called black tea mushrooms, so it seems that I like black tea.
I have never made it with green tea, but it seems that green tea is OK.
I have heard that the bactericidal action of tannins contained in tea is to suppress the growth of other germs.

Also, kombucha bacteria feed on sugar.
Therefore, I use black tea with sugar dissolved in it.
A film called scobby is made by feeding on sugar.

The rest is explained in the process of actually making kombucha.

Strategy to make natural kombucha

Acetobacter, including kombucha bacteria, is a ubiquitous bacterium in nature.
It's also floating in the air.


Acetobacter is especially found on fruits and flowers.
It is abundant in places where there is sugar in nature, such as sugar in fruits and nectar in flowers.

However, although acetic acid bacteria are attached to fruits and flowers, there are various acetic acid bacteria, so it is not always a kombucha bacterium.

How to propagate kombucha bacteria from fruits and flowers ...

Kombucha bacteria like black tea and feed on sugar, so put fruits and flowers in sugared black tea.
If it has kombucha bacteria, the kombucha bacteria will ferment to complete the kombucha drink.

When the kombucha bacteria ferment, a film called scobby is formed, so check whether the kombucha bacteria have fermented with or without the film.

Again, acetic acid bacteria are attached to fruits and flowers, but there are various types of acetic acid bacteria, so they are not necessarily kombucha bacteria.

So, try different fruits and flowers until you succeed.

Also, instead of buying fruits and flowers at the store, it's best to have something that grows naturally or is natural.
This is because the bacteria are more energetic in natural materials.

ふじりんご

So, let's experiment with apples first.
I bought an apple at a supermarket.

Experiment with apples (September 5, 2021)

りんごの皮を剥く

Peel the apples and separate into peels, fruits and seeds.
Discard the skin.
Actually, I eat.
Use the seed part.
Normally, the seed part is discarded, but since acetic acid bacteria are also attached to the seed part, use this.

In this blog's vinegar making series, we will introduce how to make vinegar with the acetic acid bacteria attached to apple seeds.

As you can see from the article in the vinegar making series, apples definitely have acetic acid bacteria that make vinegar.

Therefore, it is predicted that kombucha bacteria, which are the same acetic acid bacteria, are also attached, so we use apple seeds.

【Experimental material】Use 1300 ml wide mouth bottle
Tea leaves (Earl Gray) 14 g
Sugar 50 g
Hot water 800 ml
Ice 100 g
Vinegar 100 ml
One apple seed

Nitto Tea Earl Gray Tea 110g

Buy on Amazon Purchase at Rakuten

Black tea uses this.
The reason is that it is a cheap and good item.


Put tea leaves and sugar in a tea server, pour boiling water, and steam for about 5 minutes.


After steaming for 5 minutes, add ice to bring it to about 30 ° C.
This is because about 30 ℃ is the temperature at which kombucha bacteria can actively act.

It cools quickly in winter, so you don't have to add ice to cool it.
I prepared this in the summer, so I added ice to cool it quickly.


Pour tea into a wide-mouthed bottle.
I saw the temperature for a while, but it was still a little hot, so I added a little more ice.
Then add vinegar and apple seeds.

Vinegar is added to prevent the growth of germs.

【Bacterial characteristics of kombucha】
Kombucha bacteria like black tea (green tea is OK)
Kombucha bacteria feed on sugar
Kombucha bacteria are strong against acid
Kombucha bacteria need oxygen
Kombucha bacteria Is active around 30 ℃

Please see the characteristics of kombucha again.

Vinegar is added to prevent the growth of germs.
Kombucha is a member of acetic acid, so it is resistant to acid.
No matter how much vinegar you put in, kombucha bacteria are okay.
The more vinegar you have, the better the antiseptic effect.
However, since the purpose of kombucha is to drink, if you add too much vinegar, it will be too sour and difficult to drink, so it is good to keep it at about 10% of the amount of black tea.
About 10% can be expected to have a considerable antiseptic effect.


Do not close the lid and just put it lightly.

Kombucha bacteria need oxygen.
Therefore, please do not seal the container. However, if you open the lid, insects and dust will enter, so don't do it. Place the lid lightly to leave a gap for air to pass through.

Now leave it in a warm room.

Kombucha bacteria are active at around 30 ° C, so it is ideal to keep them in an environment of around 30 ° C.

If the temperature is low, the activity will be slow, so at least 20 ℃ is recommended.
Even if the temperature drops below 20 ° C, the activity of the bacteria will only slow down, so there is no problem even if the temperature drops below 20 ° C.
However, if the temperature is low, fermentation will be difficult to proceed, so it will take too long to complete.

Therefore, it is better to keep it in a warm place where the temperature exceeds 20 ℃.

Conversely, if the temperature exceeds 40 ° C, the bacteria will weaken, and if the temperature exceeds 60 ° C, the bacteria will die.
I don't know if there is such a place in the house where the temperature exceeds 60 ℃ even if it is a warm place.
It is better to keep it at about 40 ℃ at most.

In summer, it's best to leave it at room temperature.
In winter, it's a good idea to keep it in a warm place in a warm, heated room.
I prepared this on September 5th, so I left it at room temperature in a hot situation where the maximum temperature exceeded 30 ℃.
In such a season, a film called scobey made by kombucha will develop in about a week.

Then, after preparing it, leave it to stand without stirring.
Kombucha bacteria form colonies on the liquid surface and act, so if you stir, the colonies will break, so it is better to leave it alone.
Fermentation efficiency will be slightly reduced just because the colonies are broken by stirring, but this is not a problem.
It will recover in a few days.

6 days after preparation (September 11, 2021)


Let's open the lid and see what happens.


Oh?

There seems to be no film.

Let's take a closer look.

Two more days have passed (8 days after preparation) September 13, 2021


I opened the lid.

There seems to be no film.

It doesn't look like an apple, but let's take a closer look.

3 more days (11 days after preparation) September 16, 2021


I decided that apples are no longer good.


This is black tea that wasn't made with apples.
I'm going to put raisins here, but before that, I'll taste it to see if it's rotten.

I was fine.

At this time, I saw something like a film on the surface.


Let's shine a light and check something like a film.
It looks like a film, but this is an oil film.
The oil on somewhere will just float.

Not a kombucha scobby.

After all it was not good with apples.

Experiment with raisins (September 16, 2021)


Now let's put the raisins here.
Of course, I bought raisins at the store.
Raisins use uncoated raisins.

Raisins also have acetic acid bacteria that make vinegar.

Therefore, I add raisins in the expectation that kombucha bacteria, which are acetic acid bacteria, are also attached.

Five days have passed since the raisins were added (September 21, 2021)

Let's open the lid and see what happens.


When you shine a light, you can see something like a film, but this is an oil film.
Not a scobby.

5 more days (10 days with raisins) September 26, 2021


Let's open the lid and see what happens.


I tried to shine a light, but this is an oil film.
Apparently raisins aren't good either.

Looking back on apples and raisins

Apples and raisins have acetic acid bacteria that make vinegar, so I thought this would be a success.

But it didn't work.

Apples and raisins are available regardless of the season, so I wanted them to succeed.
For example, if kombucha is attached only to peaches, it can only be produced during the season when peaches are available.
Apples and raisins were my favorite because I could prepare them at any time of the year.

I couldn't help it, so I gave up on the materials that I could get all year round.


Next, I will try using the persimmons I bought at the supermarket and the marvel-of-Peru that bloomed on the balcony.

Prepare persimmons and marvel-of-Peru (September 26, 2021)


Since this is an experiment, I will try using a smaller bottle instead of using a 1300 ml container.
First, pour sugar-melted black tea (about 30 ℃)
and add about 10% of black tea with vinegar.
Put marvel-of-Peru in the bottle on the right.
In the jar on the left side, I cut a persimmon into a comb shape with a skin and cut it into two pieces.


Do not close the lid, just put it lightly.

It is still the season when the maximum temperature exceeds 30 ℃, so leave it at room temperature.

5 days later (October 1, 2021)


First, let's take a look at the state of the persimmon.
I opened the lid, but it seems that there is no scobby.


Let's take a look at the marvel-of-Peru.

How about?


Let's shine a light.

There seems to be a scobby.

There is a faint scobby.

4 more days (9 days after preparation) October 5, 2021


Let's take a look at the persimmon.
I tried to shine a light, but it's only an oil film.
Persimmons are useless.


Let's take a look at the marvel-of-Peru.
Obviously there is a scobby.


I think this is because the kombucha bacteria have propagated.

This preparation with marvel-of-Peru (October 5, 2021)


I will take out a marvel-of-Peru.
I couldn't remove only the flowers because it was integrated with the scobey, so I took out the scobey along with the flowers.

Kombucha bacteria are already growing in this liquid, so it is okay to remove the flowers and membranes.


In a 1300ml wide-mouthed jar, put kombucha prepared with marvel-of-Peru and black tea with sugar at about 30 ℃.

Then add about 10% of vinegar.


Kombucha bacteria need oxygen, so they do not close the lid. Just put the lid lightly.
I left it at room temperature.

8 days after the main preparation (October 8, 2021)


Let's see how it looks.
There is obviously something on the film.


You can see it by shining a light.

15 days after the main preparation (October 20, 2021)


The scobby is thicker.
It may be confirmed that this is a kombucha bacterium.


Seen from the side, it looks like this.
There is a scobby on the surface, and underneath it is like a jellyfish's foot.
This sagging is not found in the kombucha made with the starter kit.

However, since there are various types of kombucha, I presume that this is a characteristic of kombucha in marvel-of-Peru.

I will actually drink it and check it.

Drink natural kombucha


Pour into a glass with a ladle.


The taste is just kombucha.

The taste of kombucha does not change dramatically due to the fermentation of kombucha.
Since I leave the tea for many days, the flavor of the tea is fading.
And it has a sour taste because it contains vinegar, and it also has a sweet taste because it contains sugar.

In short, it tastes like sweet and sour black tea without flavor.

In this way, the bacteria that form fibrous objects on the surface of black tea containing vinegar can only be considered to be a member of acetic acid bacteria.
What if it's a strange fungus?

If you have a stomachache, I will report it.

I would like to take this every day to verify the health benefits, including whether or not I have a stomachache.

summary

That's why I found out that Kombucha bacteria are present in marvel-of-Peru.
White powder flowers are flowers that bloom from summer to autumn.
I think there are still some places that are still in bloom in October.

This time, I succeeded in marvel-of-Peru, but I think it is worth trying other fruits and flowers.
If you have succeeded with other fruits and flowers, please let us know in the comments.

Explained in the video

In the video, I am hotly talking about kombucha in Japanese.
There are some things that can only be expressed in videos, so please have a look.

-Fermented food
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