Kombucha in cold contitions


#1

Due to 2 failed growths (again fungi …) and time constraints I have performed my last experiments on kombucha leather in the early phase of its growth. The skin is therefore not yet fully developed and only a few millimeters thick. Since I have an exam next week and my last growth started to mold 2-3 weeks ago, I didn’t have enough time to produce another mature skin.

Remarkably, 2 sheets that I placed on top of each other in the freezer for a week, bonded to each other after drying and were not able to get apart at low tensile forces. By freezing, the cell structure may be broken and bonded with the other sheet. The 2 sheets also seem to have become 1. If you don’t know it is difficult or impossible to notice with the naked eye.

I also tested the reaction of a sheet of leather on dry ice.

A HUMID PIECE LEATHER on contact shrinks after + -30 seconds, after which it becomes very hard and cannot be broken if you try this by hand. After cooling for a while, the sheet takes on its original shape, but with color change.

A DRY PIECE LEATHER on contact becomes instant stiff after 10 seconds and on contact it breaks into several pieces. After cooling it returns to the same shape and color.

The wet sheet on the dry ice subsequently gave the same shape as when I let a dafalgan (paracetamol-based medicine) dry on a wet sheet. It took on a hollow shape, discolored and remained rigid and form-retaining.

At the moment I have only abandoned the idea of experimenting how Kombucha behaves under different temperatures, but also how I obtain different textures on the sheets. I also wanted to test how different acids react to sheets, but this is beyond my knowledge of chemistry… so I had to do something else and this leads to quite strange and sometimes unnecessary experiments. I have some in progress but only try to post something relevant to this platform. :slight_smile:

For example, all sorts of sheets are currently drying (in their early phase of growth due to time constraints and failed growth …) with various herbs, metals, types of wood, rocks, charcoal, etc. to obtain some texture. Hopefully cool things will come up through these experiments.

Testing with oxygen water of 3% and 30%. The oxygen water with a higher content clearly gave a stronger color change to the sheet.

while bleach does its work and the color completely disappears :stuck_out_tongue:

The sheets that are drying on the various metals already leave symptoms. Those who dry on steel and rusted steel are turning black, while those who dry on copper turn green.

The last experiment that hopefully succeeds is a sheet that is drying on a leaf to transfer the texture of the veins to the dried sheet. I think this can be a nice thing if well dried.

Now that I have to do all this with kombucha leather in its not fully mature form, I hope that this does not have too much impact on the tests, since the small thickness of the sheets …

Thijs


#2

@Ellen did some experiments with H2O2 a while back. You can see her pictures here: The smoking scoby bubble foil experiment

Seems like you didn’t get these white discolourations @thijs_baeyens … I’ve also seen kombucha leather swell up real hard in contact with H2O2. Did you add it to wet or dry sheets?

The water experiment seems not surprising at first look. In case of a humid scoby it’s really the ice that makes it unbreakable. Due to the thickness and the fact that it thaws slowly, it doesn’t break. But the thinner pieces are brittle so they break.