06 biofabricating materials
26th October - 2nd November 2021
6. BioFabricating Materials
Looking at Biofabricating Materials this week felt pretty poignant because of the current COP26 - UN Climate Change Conference...
growing mycelium¶
Starting with mycelium, here are some things I learnt:
- single cell (hyphea); nature's network
- natural binder
- removing toxins from the soil
spores>germination>mycelium>mycelium primordia (kept at this stage for material production) > fruiting body
Reisi = dense and tough
making substrates¶
- process is slow due to growing time
- controlled humidity is key:
- culture transfer from grain to plate
- pasterising/killing off external organisms from substrate
- molds need air holes
making substrates/making agar plates - softer substrates make softer mushroom - substrates can be trained as they develop into enzymes
ratio of substrate mix: measured by the handful
| hemp | coarse straw | fine straw | green tea leaves | cork | reishi |
|---|---|---|---|---|---|
| 2 | 4 | 3 | 4 | 2 | 2 |
total weight of bag=
- The idea is to create an environment for funghi to grow.
- We add flour to encourage mycelium growth and then water to the bags to make the contents moist and damp.
- I added green tea, cork and a mixture of coarse and fine straw
- Mixing softly by hand so the consistency holds shape in a clenched first with a bit of bounce-back-ability..
- Then we add Reishi and sterilise the bag on opening over a bunsen burner so that it doesn't get contaminated for innoculation
making molds¶
- Working with a premixed substrate we break down the mushroom and crumble it as much as possible.
- Compressing the mushroom into a container like a plant pot; using a glass to press the substance down as much as possible.
- Sealing with clingfilm so there is some air circulation but enough to help the fungus grow in an isolated environment
- Then leave for 5 days to dry and grow
- I made another mold with the left over substrate adding corn starch
kombucha¶
- simbiotic
- culture
- of
- bacteria and
- yeasts
I was inspired by the presentation to make red wine kombucha because of the cool colour you can achieve.
crafting bioplastics¶
Here's a picture of a food waste project by Rankin for COP26 awareness
my focus this week is on food waste because in general i want to work within a circular economy.. i was thinking about food waste i accumulate when i cook and eat etc such as date seeds....i came up with the idea of working with nut shells. i was also considering the waste content of water used for soaking beans and pulses etc - are these of any use for food waste recipes? as an alternative to date seeds i will use carob as there is quite an acculumation of them in the lab. they smell as sweet as dates and are used as a coffee substitute.
This unit also gave an introduction to the crusher machine..
You need a big amount of material to get a substantial amount of powdered or ground material back - ie. there is a reduction in the process
powdered reduction from 172g of pistachio shells
I found a recipe with nut shells suggested as an addition to potato starch bioplastic from Nature Lab. This one recommend using gelatin but I will use a substitute - Xantana.
alginate¶
Alginate is extracted from brown algae and this recipe needs 2 seperate mixtures: the alginate & the coating (calcium chloride); calcium chloride also makes the sample waterproof
| water | sodium alginate | glycerine |
|---|---|---|
| 200ml | 4g | 8g |
This recipe is a cold mix so doesn't need to be heated.
1. Measure, pour and blend the base from the measurements above.
2. Leave to set to loose the bubbles: bubbles create air pockets/inconsistencies in the substance
3. Then mix
| distilled water | calcium chloride |
|---|---|
| 100ml | 10g |
- Prepare the fabric/surface where the mixture will set by spraying the liquid to coat the base
- Use a paper towel to absorb the excess liquid of the coating
- Add the fibers/filling to the alginate mixture (powdered avocado), mix and pour onto the area to fill
- Add colour pigments (mica)
- Spray calcium carbonate on the top to seal the mixture
- Put in the dehydrator to dry
- When I remove it from the rehydrator, you can see that the substance has shrunk and curled in the heat.. has also grown some mould...
I tried this recipe again.. experimenting some more:
- Adding 4g olive oil to 8g glycerine for more elasticity
elasticity and flexibility isn't the same thing...
- Split the mixture adding ground mica and mica to one,
and orange peel with a pinch of mica to the other- Poured onto a fabric in a frame
- Then I put a layer of soft hemp sandwiched between
- Pouring some calcium carbonate into a beaker, and pressing the contents of the syringe into the mixture.. It will be coated as soon as it touches the calcium and creating these organic clusters.. the process is called calcification
- I really like the process and how they look! Obviously they're super fragile though...
starch¶
I'll work with different starches to figure out some recipes I can create a flexible, durable and elastic material:
| tapioca starch | glycerine | vinegar | water |
|---|---|---|---|
| 6g | 5g | 5ml | 50ml |
- Mix everything together cold
- Then mix until clear on a medium heat
- Stir until thicker and clear
- Then pour on a flat surface to dry
I tried this also with corn, rice and branded algae starch* / [kappa][https://www.dayelet.com/en/kappa.html]
I can already tell from the colour and consistency of some of these that they are not quite right. However, it's definitely made me want to continue to explore these recipes more and to refine them to achieve the right consistency.
I realised later that KAPPA is actually a complex polysaccharide that naturally occurs in carragenean fibres extracted from red seaweeds but also contains sodium alginate.. so I've actually worked with alginate again in this case. I want to explore more combinations of recipes and of course include the nut shells, more pigment, textures and consistencies.
tapioca - https://materiom.org/recipe/592 corn - https://materiom.org/recipe/619 potato - https://naturelab.risd.edu/discover/biomaterials-you-can-make-at-home/ https://docs.google.com/spreadsheets/u/0/d/1qsqlS64s0chwtrBIVhuULQAOUB_Bt8PIxbCyXIb8JMA/htmlview#