7. BioFabricating Materials¶
Inspiration
This week in the Bioplastics module has been incredible! I've always had a passion for materials, so exploring bioplastics has been fascinating. With my background in Crop Sciences, I see endless possibilities in creating sustainable materials. What excites me most about bioplastics is their environmental compatibility—they break down naturally without contaminating the environment, making them a refreshing alternative to conventional plastics.
Research and ideation
Biofabrication is an innovative field focused on producing sustainable materials by using living cells, organisms, or natural components. It has the potential to replace conventional manufacturing processes, offering alternatives that are biodegradable, renewable, and eco-friendly. Here’s a deep dive into research and ideation around biofabricating materials:
1. Current state of Biofabrication
Biofabrication has grown with advancements in biotechnology, 3D printing, and material sciences. Today, companies and researchers are exploring ways to produce bio-based materials for various applications, including fashion, construction, healthcare, and packaging. Key biofabricated materials already in the market include:
Mycelium-Based Leather:¶
Mycelium, the vegetative part of a fungus, can be grown to mimic leather. This material is sustainable, biodegradable, and requires less water and fewer chemicals than animal leather. Bacterial Cellulose: Produced by bacteria such as Acetobacter xylinum, bacterial cellulose has applications in wound care, food, and fashion. It’s lightweight, strong, and compostable.
Algae-Derived Plastics:¶
Algae-based polymers can be used as an alternative to petroleum-based plastics, reducing environmental impact by decomposing more easily.
Silk Proteins:¶
Produced by genetically engineered bacteria, silk proteins are used in textile manufacturing and biomedical applications due to their strength, flexibility, and biocompatibility.
2. Applications and Market Potential
The biofabrication market spans across various sectors, with significant growth potential in:
Fashion and Textiles:¶
Biofabricated textiles and leathers are being developed to reduce the carbon footprint of the fashion industry. For example, bio-based leather alternatives provide a cruelty-free and less resource-intensive option.
Healthcare:¶
Biofabrication enables the production of scaffolds for tissue engineering, which could support regenerative medicine. For instance, bioengineered cartilage or skin could be used in reconstructive surgery.
Packaging:¶
Sustainable bio-based packaging made from algae or bacterial cellulose can replace traditional plastic packaging, reducing environmental waste.
Construction:¶
Biofabricated materials like fungal mycelium-based bricks are being tested for building applications due to their insulation properties and sustainability.
3. Emerging Biofabrication techniques Biofabrication relies on a variety of emerging techniques that combine biology and material science:
Synthetic Biology:¶
Engineers use synthetic biology to program microorganisms, such as yeast or bacteria, to produce specific proteins or materials. This technique has enabled the production of materials like spider silk without the need for spiders.
Bioprinting:¶
In biofabrication, 3D bioprinting involves printing with living cells or bio-inks to create structures that mimic natural tissues. This technique is still in early stages for consumer products but has exciting potential.
Fermentation:¶
Microbial fermentation can be harnessed to grow materials, as seen in Kombucha SCOBY (Symbiotic Culture of Bacteria and Yeast) leather. This material is grown from tea, sugar, and bacterial cultures, and has applications in fashion and packaging.
Mycelium Cultivation:¶
Mycelium can be cultivated in molds to form specific shapes and textures, and its use in fashion, furniture, and packaging materials is expanding rapidly.
Bioplastic from tree tomato
Bioplastic from tree tomato (tamarillo) waste utilizes the fruit's natural compounds to create a sustainable, biodegradable material. By processing the pulp with glycerol and gelatin or agar, the mixture can be molded into films or shapes that degrade naturally, offering an eco-friendly alternative to petroleum-based plastics. This bioplastic reduces food waste, minimizes environmental impact, and has potential applications in packaging, agriculture, and disposable items, contributing to sustainable innovation in material science.
Tools
For making bioplastic from tree tomato waste, you can actually use simple, everyday kitchen tools. Here’s what you’ll need:
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Spoons: For measuring and adding ingredients like glycerol and vinegar. A standard tablespoon and teaspoon set will work.
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Fork or Whisk: To mix and stir ingredients, ensuring everything blends evenly.
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Bowl: A medium-sized, heatproof bowl for combining all ingredients.
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Pot or Saucepan: For gently heating the mixture on the stovetop. A small or medium pot will do.
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Measuring Cups: For measuring water and other liquid ingredients accurately.
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Blender or Masher: If you have one, use a blender to create a smooth tree tomato paste. If not, a fork or potato masher can work, though it may take a bit longer.
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Flat Plate or Tray: To pour the bioplastic mixture onto for setting. A baking tray or any flat, non-stick surface works well.
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Spatula: For scraping the bowl and spreading the mixture evenly on the tray.
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Non-Stick Surface (e.g., Wax Paper or Parchment Paper): Place this on the tray before pouring to prevent sticking
Safety Tools¶
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Gloves: Useful if handling hot surfaces or sticky ingredients.
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Heat-Resistant Mat or Trivet: For placing hot pots and bowls on a safe surface.
Ingredients & Recipes
To create bioplastic from tree tomato (tamarillo) waste, you can follow a basic recipe that uses fruit waste combined with other bioplastic ingredients.
Here’s a simple recipe you can try: Ingredients:
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Tree Tomato (Tamarillo) Waste - 100 grams You can use leftover skins, pulp, or juice from the fruit.
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Glycerol (Glycerin) - 1 to 2 tablespoons Acts as a plasticizer, giving flexibility to the bioplastic. You can adjust the amount based on desired flexibility.
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Gelatin or Agar Powder - 10 grams Provides structure to the bioplastic. Gelatin is animal-derived, while agar is plant-based.
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Water - 100 ml Used as a solvent to dissolve the gelatin/agar and mix everything together.
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Vinegar (optional) - 1 teaspoon Helps maintain the integrity of the bioplastic, especially when using gelatin.
Process and Workflow
Instructions:
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Prepare the Tamarillo Paste: Blend the tree tomato waste with a bit of water until you get a smooth paste.
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Dissolve the Gelatin/Agar: In a saucepan, combine water with gelatin or agar powder. Heat gently and stir until it’s fully dissolved.
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Combine Ingredients: Add the tamarillo paste and glycerol into the dissolved gelatin/agar mixture. Stir well until everything is fully combined.
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Optional: Add Vinegar: Add vinegar if you're using gelatin to help with the plastic's stability.
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Heat Mixture: Gently heat the mixture until it thickens, stirring continuously to prevent lumps.
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Pour and Set: Pour the bioplastic mixture into a mold or spread it out on a flat surface to set. Let it cool and harden for at least 24 hours.
Here’s a step-by-step heating process for making bioplastic from tree tomato waste:
Heating Process
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Prepare a Double Boiler Setup (Optional but Recommended):
If possible, use a double boiler to prevent overheating. Place a heatproof bowl over a saucepan of simmering water. This helps control the heat and prevent the mixture from burning.
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Initial Heating of Water and Gelatin/Agar:
In a saucepan (or the double boiler), add 100 ml of water and sprinkle in 10 grams of gelatin or agar powder.
Begin heating the mixture over medium-low heat, stirring continuously to ensure the gelatin/agar dissolves completely and there are no lumps.
Do not allow the mixture to boil, as boiling can break down the gelatin/agar structure, affecting the bioplastic’s texture. Aim for a temperature between 70-80°C (158-176°F).
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Add Glycerol and Tamarillo Paste:
Once the gelatin/agar is fully dissolved, add the 1-2 tablespoons of glycerol and the prepared tamarillo paste.
Continue to stir the mixture, ensuring that the glycerol and tamarillo paste are evenly incorporated.
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Heat for a Few Minutes to Thicken:
Keep the mixture on medium-low heat for another 5-10 minutes, stirring continuously. The mixture should gradually thicken to a syrup-like consistency.
If you’re using vinegar, add 1 teaspoon at this stage to help stabilize the plastic.
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Check for Consistency:
You want the mixture to be thick but still pourable. Avoid letting it boil, as high temperatures can cause the material to degrade.
If the mixture starts bubbling too much, reduce the heat immediately.
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Remove from Heat and Pour:
Once the desired consistency is reached, remove the mixture from heat.
Quickly pour the bioplastic mixture into your mold or onto a flat, non-stick surface, as it will begin to set as it cools.
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Cool and Set:
Allow the bioplastic to set at room temperature for 24-48 hours, depending on thickness. For faster drying, you can place it in a well-ventilated area.
My challenges with this experiment
Despite promising progress in the formation of tree tomato bioplastic after five days, the experiment faced an unexpected setback when it was unintentionally ruined in the lab. This incident halted the process before reaching the final outcome, highlighting the importance of careful handling and lab protocols in experimental projects.
Three days later¶
Conclusion
The result of making tree tomato bioplastic demonstrates its potential as a sustainable material. Within five days, the bioplastic started to form, showcasing its ability to create a stable structure. This indicates that tree tomato could be a viable raw material for eco-friendly bioplastics, offering an alternative to synthetic plastics. The process aligns with sustainability goals, as it leverages organic components, reduces reliance on petroleum-based plastics, and supports environmentally conscious innovation.
Exploring the Potential of Tree Tomato Waste for Sustainable Biomaterials
After discovering that tree tomato waste is a promising resource for biomaterial development, I was inspired to take my experiments further. I loved the potential it showed in my initial trials, and I am eager to modify the recipe to explore different properties that could enhance its application. My goal is to experiment with various natural additives and substitutes to achieve improved elasticity, tensile strength, and durability, making the material more versatile. Additionally, I want to experiment with natural colorants and essential oils to enhance its aesthetic appeal and scent, creating a more appealing and functional bioplastic. This new direction excites me, as it allows me to push the boundaries of sustainable design and discover innovative solutions for eco-friendly products.
Modified recipe
Here's a modified recipe for tree tomato bioplastic using alternative, more accessible, and biodegradable ingredients while maintaining key properties like flexibility, strength, and durability.
Modified Recipe (with Substitutes):¶
- Tree Tomato Waste – 100 grams (natural polymer source)
- Glycerol (Glycerin) – 1 to 2 tablespoons (for flexibility and moisture retention)
- Gelatin – 10 grams (for gel formation and structure)
- Water – 100 ml (to blend and dissolve ingredients)
- Vinegar (optional) – 1 teaspoon (to adjust pH and increase durability)
- Cornstarch – 10 grams (for film strength and elasticity)
- Egg white – 5 to 10 ml (for elasticity and binding)
- Gelatin & Glycerin Mix – 5 to 10 grams (for flexibility and water solubility)
- Sodium Alginate – 2 to 5 grams (for structural support)
- BeesWax – 5 grams (for water resistance and texture)
Instructions
Step 1: Prepare Tree Tomato Paste¶
- Blend the tree tomato waste (100 grams) with 100 ml of water until you achieve a smooth consistency.
- Strain the mixture to remove large fibers if necessary, ensuring a smooth paste.
- Set aside the paste for later use.
Step 2: Mix Dry Ingredients¶
- In a saucepan (off heat), combine:
- 10 grams of gelatin
- 10 grams of cornstarch
- 2 to 5 grams of Sodium alginate
- Add about 50 ml of water (half the total amount) and stir thoroughly until all the dry ingredients are fully dissolved.
- Gradually add the remaining 50 ml of water, continuing to stir until a uniform mixture is achieved.
Step 3: Heat the Mixture¶
- Place the saucepan on medium heat and stir constantly to prevent clumping.
- Once the mixture starts to thicken, add:
- 1 to 2 tablespoons of glycerol (glycerin) for flexibility and moisture retention.
- 1 teaspoon of vinegar (optional) to adjust pH and improve durability.
- Continue stirring and heating gently for about 5-10 minutes, ensuring it becomes smooth and slightly thickened.
Step 4: Incorporate Binding Agents¶
- Gradually add eggwhite of 1 egg while stirring continuously to avoid lumps.
- Stir in 5 to 10 grams of the gelatin & glycerin mix, ensuring it blends evenly to enhance flexibility and water solubility.
- Continue cooking and stirring for an additional 5 minutes, allowing the mixture to homogenize.
Step 5: Add Wax¶
- In a separate small pan, melt 5 grams of Beeswax over low heat until fully liquefied.
- Slowly pour the melted wax into the heated mixture while stirring continuously.
- Stir for another 3-5 minutes until fully incorporated and smooth.
Step 6: Pour and Dry¶
- Remove the saucepan from heat and immediately pour the mixture onto a flat surface or into molds, spreading it evenly.
- Allow the mixture to cool at room temperature for about 30 minutes.
- Leave it to air dry for 24-48 hours, or use a dehydrator set at 40°C to speed up the drying process.
Step 7: Final Touches¶
- Once dried, gently remove the bioplastic from the surface or mold.
- Test for flexibility and durability; store in a cool, dry place.
Expected Properties:¶
- Flexibility: Glycerol and egg white improve elasticity.
- Durability: Beeswax enhances water resistance.
- Eco-friendliness: All ingredients are biodegradable and non-toxic.
- Customization: You can adjust glycerin for softness or starch for firmness.
Banana peels Bioplastic
Creating bioplastic from banana peels is a fascinating and eco-friendly project! Banana peels are rich in starch, cellulose, and lignin, making them a viable material for bioplastics. Here's a simple guide:
Materials Needed:¶
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Banana peels
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Starch
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BeeWax
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Water
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Blender
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Saucepan or microwave-safe bowl
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Stove or microwave
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Spatula or stirring rod
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Mold or flat surface for drying
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Measuring tools
Step-by-Step Process
- Preparation Peel and Clean: Collect banana peels and rinse them to remove any residues. Chop: Cut the peels into small pieces to make blending easier.
- Blending Place the chopped peels in a blender. Add a small amount of water to assist the blending process. Blend until you get a smooth pulp.
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Heating Transfer the pulp into a saucepan. Add: 2 tablespoons of vinegar to help dissolve the starch and cellulose. 1–2 teaspoons of glycerin for flexibility (optional). Heat the mixture over low-medium heat, stirring constantly. The goal is to thicken the mixture without burning it. This step helps the bioplastic to polymerize.
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Forming the Plastic Once the mixture thickens to a paste-like consistency, pour it onto a mold, tray, or flat surface. Spread the mixture evenly using a spatula to achieve the desired thickness.
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Drying Allow the bioplastic to dry completely. This could take 1–2 days at room temperature or a few hours in a low-temperature oven (~50°C or 122°F).
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Finishing After drying, remove the bioplastic from the mold. Trim the edges and test its flexibility and durability.
Tips for Optimization
Texture Control: Blending the peel pulp thoroughly ensures a smoother texture.
Additives: Experiment with natural dyes, essential oils, or other additives for color, fragrance, or enhanced properties.
Reinforcement:Incorporate natural fibers (like jute or hemp) for added strength.
Ripe banana Bioplastic
Ingredients
- Ripe Banana (mashed and strained) – 200 grams (natural polymer source)
- Water – 200 ml (to dissolve ingredients)
- Glycerol (Glycerin) – 4 tablespoons (for flexibility and moisture retention)
- Agar Powder – 20 grams (for gel formation and structure)
- Cornstarch or Tapioca Starch – 30 grams (for strength and elasticity)
- Honey – 2 tablespoons (for elasticity and moisture balance)
- Vinegar (optional) – 1 teaspoon (to adjust pH and increase durability)
Instructions
Step 1: Prepare the Banana Paste¶
- Mash 200 grams of ripe banana and blend with 100 ml of water until a smooth paste forms.
- Strain to remove large fibers for a smoother texture.
- Set aside.
Step 2: Mix the Dry Ingredients¶
- In a saucepan (off heat), combine:
- 20 grams of agar powder
- 30 grams of cornstarch or tapioca starch
- Add the remaining 100 ml of water, stirring thoroughly to dissolve the powders.
Step 3: Heat the Mixture¶
- Place the saucepan over medium heat, stirring continuously to avoid lumps.
- Once the mixture begins to thicken, add:
- 4 tablespoons of glycerol
- 1 teaspoon of vinegar (if using, for increased durability)
- Continue stirring for 7-10 minutes until the mixture becomes smooth and slightly thickened.
Step 4: Add Honey for Flexibility¶
- Reduce heat to low and slowly stir in 2 tablespoons of honey.
- Mix well for another 5 minutes to ensure it’s evenly incorporated into the mixture.
Step 5: Pour and Dry¶
- Remove the saucepan from heat and pour the mixture onto a flat, non-stick surface (such as a silicone sheet).
- Spread it evenly to the desired thickness.
- Allow it to cool at room temperature for about 30 minutes.
- Let it air dry for 24-48 hours, or use a dehydrator at 40°C to speed up the drying process.
Final Processing:¶
- Once fully dried, gently peel off the bioplastic from the surface.
- Test for flexibility and durability.
- Store in a cool, dry place to avoid moisture absorption.
References