7. BioFabricating Materials¶
Research and Inspiration¶
Loop Biotech's Mycelium Coffins
Ideation¶
Process and Workflow¶
I referred to Loes Boger's absolutely amazing 24 Core recipes
Weather Notes : It is November in Mumbai and the weather is supposed to be turning from the September monsoon through October heat to the first touches of winter (in as much of a winter we can possibly have at this latitude - no, seriously, Mumbai breaks out the jackets at 22 C while Delhi sniggers through their smog) However, it has been RAINING ALL WEEK this week, as well as intermittently all October. We have had very weird weather and all weather metrics, growth, drying, and other such timelines have gone sideways.
Crafted - Gelatin based¶
I decided to try out gelatin based materials :
Polymer : Gelatin
Plasticizer : Glycerin
Solvent : Water
Colour : Food colours, Biochrome dyes
Fillers : Terracotta clay, expired POP powder, rice husk, post-brew tea leaves
Materials created :
- Bioresin
- Biosilicone
- Biofoam
- Biofoil
Proportions of ingredients vary for each material, given in the recipes below.
Recipes¶
Based on the recipes from Loes Bogers' 24 core recipes, I have scaled up the yield to 800 ml of each material, before cooking and reduction.
| Recipe | Ingredients | Basic Instructions | Drying & Shrinkage |
|---|---|---|---|
| Bioresin Rigid, glass-like translucent material |
• 128 g gelatine • 21 g glycerine • 640 ml water • Coffee filter (optional) |
→ Heat water + glycerine (do not boil). → Sprinkle in gelatine while stirring until clear and viscous. → Skim foam with coffee filter. → Pour slowly into molds; air-dry. |
Drying: 5–7 days Shrinkage: 5–15 % |
| Biosilicone Flexible, rubber-like sheet with soft gloss |
• 154 g gelatine • 154 g glycerine • 770 ml water |
→ Heat water to 75–80 °C. → Add glycerine, then gelatine gradually; stir 20–25 min until syrupy. → Pour into molds; alternate pressing overnight / air-drying by day. |
Drying: 5–10 days Shrinkage: 20–30 % thickness / 10–20 % width-length |
| Biofoam Soft, spongy, open-cell foam |
• 48 g gelatine • 48 g glycerine • 600 ml water • 4 tsp (≈ 20 ml) dish soap |
→ Heat water (not boiling). → Dissolve gelatine + glycerine. → Remove from heat; add soap and whip until airy. → Pour into shallow trays. |
Drying: 2–3 days Shrinkage: 30–50 % thickness / 5–10 % width-length |
| Biofoil (Extra Flexible) Thin, flexible, translucent film |
• 64 g gelatine • 48 g glycerine • 530 ml water |
→ Bring water near boil (< 80 °C). → Add glycerine, then sprinkle gelatine; stir until smooth and syrupy. → Pour thinly on non-stick sheet. |
Drying: 2–4 days Shrinkage: 30–50 % thickness / 5–10 % width-length |
BioResin¶
I calculated the number of samples and variants I was going to create and decided 800 ml of starting mixture would suffice. It reduced to about 600 ml before pour, and I was left with some excess as well. Therefore, for the later recipes, I have aimed at 500-600 ml starting mix.
Bioresin – 800 ml
Ingredients
- 128 g Gelatine
- 21 g Glycerine
- 640 ml Water
- Coffee filter (optional)
Process
- Heat water + glycerine.
- Gradually add gelatine while stirring until clear and viscous.
- Skim foam with a coffee filter.
- Pour slowly into molds; dry 5–7 days.
Expected Result
Rigid, glass-like translucent resin.
Expected Shrinkage
5–15 % overall.
Adapted from Loes Bogers, Fabricademy 2020 – Bioresin.
Fillers :
- Natural/no filler
- Terracotta clay,
- expired POP powder,
- rice husk
Colour : Red food colour
Process¶
- I cooked the recipe as per the measurements
- I put the various fillers into the molds directly
- Then added the liquid and mixed in the fillers
- Once the natural batch was done, added 1 drop of red food colour to the mix
- Repeated the filler and mix process for the coloured version as well
- I let everything sit for ___ days before demolding
Observations¶
24 hours later
- The next day, the pieces had set enough to be touched, but were still tacky when touched, leaving fingerprints although barely so
- The Rice Husk variant had thickened in the lower layers but the upper layers were actually very liquid still. All other variants had set as describe above. Something about the rice husk may be preventing the gelatin to set ?
48 hours later
- everything had MOLD growing !!! I suspect that, since I put all the trays under clingwrap to avoid dust and particles falling in to the setting gels, air circulation was cut off. The resin did not dry at the expected rate, and the warmth and moisture provided a ripe environment for mold to grow
- I wiped it off as best as I could, but the surface has definitely suffered, more from the wipe than the mold, actually.
Results¶
BioSilicone¶
Biosilicone – 600 ml
Ingredients
- 116 g Gelatine
- 116 g Glycerine
- 580 ml Water
Process
- Heat water to 75–80 °C.
- Add glycerine first, then sprinkle in gelatine while stirring.
- Stir 20–25 min until smooth and syrup-like.
- Pour into molds; alternate pressing overnight / air-drying by day for 5–10 days.
Expected Result
Flexible, rubber-like sheet with soft gloss.
Expected Shrinkage
20–30 % thickness / 10–20 % width-length.
Adapted from Loes Bogers, Fabricademy 2020 – Biosilicone.
Fillers :
- Natural/no filler,
- Terracotta clay,
- expired POP powder,
- rice husk,
- used tea leaves from kombucha brewing
Colour : Blue pea dye from the Biochrome week in some samples, blue food colour in others
Process¶
- I cooked the recipe as per the measurements
- I put the various fillers into paper cups
- Then added the liquid to paper cups mixed in the fillers
- Poured the natural colour samples into the molds, leavimg enough to make coloured versions
- Added 1 tsp of Blue Pea to each papercup and mixed
-
Poured the coloured filler mixes into the molds
-
For the remaining leftover material, added a drop of food colouring and poured it into various other molds, voluminous as well as flat
-
I let everything sit for ___ days before demolding
Observations¶
0 hours
- The mix began to set almost immediately, the natural versoin was setting by the time I finished mixing and pouring the coloured version
Results¶
Biofoam¶
Biofoam – 600 ml
Ingredients
- 36 g Gelatine
- 36 g Glycerine
- 450 ml Water
- 3 tsp Dish soap (≈ 15 ml)
Process
- Heat 450 ml water (not boiling).
- Add gelatine + glycerine; stir until fully dissolved.
- Remove from heat, add dish soap, and whip until airy foam forms.
- Pour into shallow molds or trays; dry 2–3 days at room temperature.
Expected Result
Soft, spongy, open-cell foam.
Expected Shrinkage
30–50 % thickness / 5–10 % width-length.
Adapted from Loes Bogers, Fabricademy 2020 – Biofoam.
Fillers :
- Natural/no filler
- Terracotta clay,
- expired POP powder,
- rice husk
- brewed tea leaves
Colour : Yellow food colour
Process¶
- I cooked the recipe as per the measurements
- Foamed it with the electric whisk/eggbeater
- Initially used detergent, but then used dishwasher liquid
- I put the various fillers into paper cups
- Then added the liquid mix to paper cups and gently folded in the fillers, like for cake batter, to better preserve the bubbles entrained into the mix
- Poured the natural colour samples into the molds, leavimg enough to make coloured versions
- Added 1 tsp of Yellow food colouring and mixed
- Poured the coloured filler mixes into the molds
- I let everything sit for ___ days before demolding
Observations¶
- Liquid laundry detergent does not give the requisite foam, it has to be dish soap
- Fold the fillers in gently or you will damage the air entrapment
- The foam started to set almost immediately
- Fillers with large particle size - tea leaves and rice husk - ended up collapsing more, destroyin their larger bubbles faster
Results¶
Grown - Kombucha bacterial leather¶
Recipes¶
Kombucha / Bacterial Leather
Ingredients
For 1 liter / 1 kg brew mix
Sweet tea
- 750 g (or ml) Water
- 50 g Jaggery (or cane sugar)
- 6 g Organic black tea (loose or 3–4 tea bags)
- 200 g Starter culture (Kombucha liquid + cellulose)
Proportions
- Sweet Tea: ≈ 900 g (90 %)
- Starter Culture: ≈ 100 g (10 %)
Process
- Boil 750 g (or ml) water.
- Add 50 g jaggery and stir until fully dissolved.
- Add 6 g organic black tea; steep for 10–15 minutes to extract color and tannins for stronger microbial activity.
- Strain out tea leaves and allow the sweet tea to cool to below 30 °C.
- Gently add 200 g starter culture (do not stir vigorously).
- Pour into a wide, shallow, sterilized glass or plastic container.
- Cover with breathable muslin or cotton cloth secured with an elastic band.
- Incubate at 25–30 °C in indirect light for 10–21 days until a cellulose mat (SCOBY) forms.
- Harvest when 3–5 mm thick.
Post-Processing
- Rinse the SCOBY thoroughly in clean water.
- Soak in a mild vinegar bath (pH ≈ 3–4) to neutralize.
- Dry flat on a non-stick sheet at room temperature or at 35–40 °C until leathery.
- Optionally condition with glycerine or beeswax for flexibility and waterproofing.
Notes
- Black tea provides tannins that enhance microbial activity and strengthen cellulose fibers.
- Avoid metal vessels; use glass, plastic, or glazed ceramic.
- Expected yield: roughly A4-sized sheet, ~2–3 mm thick when wet.
For the Kombucha based bacterial leather, I took refuge in my sister's fermentarium. She is a pastry chef with a huge interest in ferments - she regularly makes and sells kombucha, kvass, and a variety of lacto-ferment based pickled veggies, kimchi, and so on.
I borrowed the SCOBY from her hotel for starting the culture. She oversaw me during this whole process and guided me.
- We followed the recipe above, which is based off her working recipe, but the culture has been doubled to speed up the growth
- First we made the sweet tea using jaggery (instead of the usual sugar), and looseleaf black tea
- We let that cool to 30-35 C since higher temperatures would kill off the culture
- Once cooled, we mixed in the culture
- I had picked up rectangular plastic cupcake box covers that I though would make good rectangular sheets of Kombucha paper and leather, so we filled those up
- Since we had excess liquid left, we filled up other containers as well
- I filled up some molds, hoping that the leather pieces come out in the shape of the silhouette of the mold
- Added some to paper cups and added food colour to 2 of them, hoping the leather may acquire a coloured tint due to that
- Since there is a SCOBY hotel here and my sister tosses away the pellicles regularly, I also wanted to use the existing pellicle to set it to dry and turn into leather. However, due to the misfiring weather, I have decided not to do that. The pellicle is quite thick even after separating the layers, suffused with water, and will very likely catch mold long before it manages to dry out.
- We do have a dehydrator here as well in the fermentarium, but that is energy intensive and I'll choose that option if the weather continues to misbehave, or atleast stabilises
Harvest¶
Drying and preservation¶
Observations¶
- 24 hours : streaky growth is forming
- While it typically is faster, the weather has cooled down due to absolutely unseasonal rains, and all metrics are off