Kombutex
by Guoda Treciokaite
Berlin Design Week - Design & Science - Circular Fashion Exhibition
Exhibit 1: Sheet of bacterial cellulose
A sheet of treated bacterial cellulose. The biofilm was grown in a static culture of kombucha in a large rectangular container. The kombucha medium was prepared by combining kombucha starting liquid, SCOBY (Symbiotic Culture of Bacteria and Yeast), black tea and sugar. After a couple of weeks of fermenting at a temperature of approximately 28°C, a thick biofilm of bacterial cellulose was grown. It was cleaned and processed with plant-based glycerol to make it flexible, then dried. After drying, it was once again treated with glycerol. The result is what you see on the table.
Exhibit 2: Samples of SCOBY
Samples of treated bacterial cellulose directly taken from SCOBY (Symbiotic Culture of Bacteria and Yeast). When bacterial cellulose is grown during kombucha fermentation, it takes up the shape of the container. SCOBY or the mother culture of kombucha has a circular shape because it is usually grown in jars. One can experiment with the shape of the fermentation container to obtain different shaped bacterial cellulose.
Exhibit 4: Lab samples of bacterial cellulose Air-dried (left) and freeze-dried (right) samples of bacterial cellulose (BC). The BC samples were dried in different ways to see the effect the drying process would give to the structure of the polymer matrix. The sample on the left was naturally dried in air. The matrix of the cellulose fibres collapsed when the water evaporated hence the thin structure of BC. The sample on the right was freeze-dried. The sample was frozen to obtain a crystalline structure of water molecules within the polymer matrix. It was then dried at high pressure which sucked the water molecules very fast from the polymer matrix allowing it to retain the crystalline structure. The freeze-dried sample has a white colour (colour of cellulose fibres) and looks and feels like foam. (Lab samples: courtesy of Peng Tang, AG Haag, Institute of Chemistry and Biochemistry FU Berlin)
Exhibit 5: Molecular images of bacterial cellulose
Molecular images of air-dried (Image 1, left on the table) and freeze-dried (Image 2, right on the table) bacterial cellulose (BC) were taken with a Scanning Electron Microscope (scale of 2 - 10 micrometers). The structure of BC collapses when air-dried (Image 1). When freeze-dried, the water molecules are sucked out of the frozen BC structure (frozen while wet) so we are able to see the crystalline structure of the cellulose matrix (Image 2). The white strands in the images are the pure cellulose fibres.
Image 1: SEM (Scanning Electron Microscopy) images of dried bacterial cellulose at different resolutions. (courtesy of Peng Tang, AG Haag, Institute of Chemistry and Biochemistry FU Berlin)
Image 2: SEM (Scanning Electron Microscopy) images of freeze-dried bacterial cellulose at different resolutions. (courtesy of Peng Tang, AG Haag, Institute of Chemistry and Biochemistry FU Berlin)Exhibit 6: Samples of bacterial cellulose on fabric Samples of treated bacterial cellulose (BC) sewn on fabric. The BC samples were sewn on different types of natural fabric to see what the BC material would look like in a lined bag.
Exhibit 6: Kombutex bag The final product is the Kombutex bag made from bacterial cellulose.
© Guoda Treciokaite 2023