Making bioplastics In this book you will find recipes for making bioplastics using various biopolymers as well as food-waste materials. We highly recommended to start with the 'Beginners Guide to Cooking Bioplastics' which will give you the most important information to get you going, plus to easy recipes to start off with. Please be advised; As is common for all bio-based materials, you will need to take the time to engage yourself with the process, the quality of your results will grow with practice and experimentation.  101 - Beginners guide to cooking bioplastics On this page you will find the most important information plus two easy recipes to get you going. Lab Pastoe also offers an in-depth course on making biomaterials, on two consecutive Wednesday evenings from 18:30 - 21:30. Please see the reservation tool for upcoming events or send an email to labpastoe@hku.nl. What are bioplastics made of? As with 'industrial' plastics, bioplastics are made by combining a polymer to make the material strong, with a  plasticizer to make the material flexible, and something to mix and dissolve the two in. Extra ingredients can be colorants and fillers , to give the material color, texture and added characteristics such as sturdiness, ferromagnetism or conductivity. Over the years we learned that a few drops of essential oil help prevent bacterial and fungal growth. Biopolymers we often use are gelatin, agar, alginate, chitine, cellulose, carrageenan and starch. Plasticizers we use are vegetable glycerine and sorbitol. We mix and dissolve these ingredients in water . As colorants we often use natural dyes, teas, food colorings or mica powders, and as optional fillers we use dried organic debris or (food) waste materials such as coffee, eggshells, sawdust, wool, textiles etc. We have a collection of all of these, some for sale, some free to use. Please ask staff about it. Which tools do I need? To cook bioplastics you will need a scale to weigh ingredients, an electric or induction cooker , a pan , a wooden spoon to stir, a measuring beaker and a cooking thermometer . All of these you can find in the cabinet in the washing-up / screenprinting room at Lab Pastoe. You will also need a mold to cast your material in or on. The easiest way to cast flat materials is to use a wooden embroidery hoop , in which you clamp some pvc plastic (which can take heat) or waterproof textile. You can find these in the washing-up / screenprinting room or under the drying table at Lab Pastoe. == The upside of using an embroidery hoop, is that the bioplastic will stick to the wood, but not to the plastic. This means that after your material gellifies enough (about 24-48 hours), you will be able to remove the outer hoop and the plastic from your material, and leave the material attached to the inner hoop to dry upright, with air able to flow on both sides of your material, speeding up the drying process. == Assembling ingredients and cooking You can find all polymers, glycerine, colorants and fillers in the window cabinet in the office at Lab Pastoe. Please ask staff which are free to use, and which have a price. To start, you can choose one of these two easy recipes, based on gelatine (not vegan, easier to use) or agar (algae-based, vegan): Biosilicone (gelatine-based) This is a flexible bioplastic that can be also used in the sewing machine to embroider on. Ingredients for a medium-sized embroidery hoop: Gelatine 48 gr Glycerine 24 gr Water (or dyed water) 240 ml Two drops of essential oil Assemble your ingredients, your mold/hoop and tools. Bring the water to a boil. (optional: replace part of the water, or all the water, with natural dye if you want a colored foil). Add the glycerine to the boiling water, and then add the agar. While the water is still boiling, dissolve the agar by stirring gently. Once the agar is fully dissolved, lower the heat to about 70 degrees and add the essential oil. Keep the mixture on this heat and stir gently for about 20-40 minutes until you see the mixture gellify into the consistency of a syrup. A thicker mixture renders a thicker foil after drying, also a thicker mixture (with more water evaporated) dries more quickly. Then cast the mixture in your hoop or on a surface. Leave to dry in a food dehydrator at lowest temp, near a heater or in a ventilated area. !! Always add a note with your name, material and date to your material when it is drying at Lab Pastoe. It is your own responsability to keep an eye on the drying process. After 10 days, materials that have not been picked up will be remelted and used again. Agar bioplastic (algae-based) This is a very flexible foil. Ingredients for a medium-sized embroidery hoop: Agar 5 gr Glycerine 15 gr Water (or dyed water) 250 ml/gr Two drops of essential oil Assemble your ingredients, your mold/hoop and tools. Bring the water to a boil. (optional: replace part of the water, or all the water, with natural dye if you want a colored foil). Add the glycerine to the boiling water, and then add the agar. While the water is still boiling, dissolve the agar by stirring gently. Once the agar is fully dissolved, lower the heat to about 70 degrees and add the essential oil. Keep the mixture on this heat and stir gently for about 20-40 minutes until you see the mixture gellify into the consistency of a syrup. A thicker mixture renders a thicker foil after drying, also a thicker mixture (with more water evaporated) dries more quickly. Then cast the mixture in your hoop or on a surface. Leave to dry in a food dehydrator at lowest temp, near a heater or in a ventilated area. Have a look at this cooking video from Fablab Barcelona that uses a slightly different method to make agar foil: !! Always add a note with your name, material and date to your material when it is drying at Lab Pastoe. It is your own responsability to keep an eye on the drying process. After 10 days, materials that have not been picked up will be remelted and used again. Drying biomaterials After about 24-48 hours (for agar it can take longer) take off the outer hoop and peel your bioplastic (which is now still attached to the inner hoop) off the plastic or waterproof fabric. If you find that it is not strong enough to do so, leave it to dry for another 8 hours. Clean the hoop and plastic with hot water, dry and store back in the crate. Dry your material upright in the hoop for another 5 or 6 days in a ventilated area. When completely dry (no longer cold to the touch) cut it out of the inner hoop. Clean the hoop with hot water, dry, and store back in the crate. Post processing Bioplastics can be lasercut, sewn (when using a sewing machine, transport goes better when you attach some thin paper under and on your material), remelted over an object with a heat gun, silkscreened on, used as glue... just experiment, don't forget to document your process, and get to know the material! !! This was a quick and simple starting guide. Feel free to explore all the other recipes and cook books available on these pages, or sign up for our in-depth biomaterial course. Have fun! Gelatin bioplastic recipes Gelatin is made from collagen present in animal parts and comes in jelly, sheet or powder, which is the form we use in the recipes below. Gelatin is a spiral waste product from the meat industry, being repurposed for uses outside of that industry. Material properties: Water resistance: Gelatine bioplastics start dissolving after a couple of hours when submerged in room temperature water. It instantly melts when submerged in water of > 60C.  Heat resistance: Gelatine bioplastics aren't heat resistant and will start melting between 30-50C. When microwaved, the material dissolves quite quickly.  RECIPE #1: Basic gelatin bioplastic This is the basic mix from which you can start playing around with more or less glycerine. It is also a great and fairly flexible recipe for composites (e.g. with textiles) and mixtures with powders or other dry elements. This recipe yields appr. 250 ml of material to be cast (depending on the amount of water that you let dissipate during the cooking process). Image credit: Clara Davis. Gelatine 48 gr Glycerine 12 gr Water 240 ml Two drops of essential oil Mix the gelatine with the cold water in your pot, and stir until dissolved. Warm up the mixture on your stove to a max of 80C. Add your plasticizer and two drops of essential oil. The general rule is: the more glycerine, the more flexible the material, but do not exceed 1:1. Simmer for 15 minutes while stirring regularly, then let the liquid cool for a couple minutes while stirring, until it gels a little but is still liquid. The mixture should be at least honey-like before casting. Remove any froth with a spoon, or absorb it using a coffee filter or kitchen paper (cartouche). TIP: Longer cooking time (up to an hour) allows more water to evaporate and will dramatically reduce shrinkage of your casted object. You will get a thicker liquid. To cast larger volumes and solids with this recipe, evaporate a lot of water, until it's very very thick. Sometimes it's worth reheating and melting scraps, they've already dissipated a lot of water and result in nice castings. Optional: Add a filler and mix gently until it is evenly distributed throughout the liquid. Slowly, and while keeping the flow in one place to avoid air bubbles, pour the mixture in your mould or on your chosen surface. Note: Don't cast hot bioplastic on acryllic that is thinner than 7mm, it will bend. Drying / curing: Let the material dry in a ventilated and dry room and de-mould when your plastic feels solid, but still cold to the touch - often after 24-48 hours. Keep ventilated and regularly turn your piece over until it is dry, so as to avoid mold formation with long drying times. RECIPE #2: Bio Resin This creates a hard, resin-like material. This recipe yields appr. 200 ml of material to be cast. Image credit: Loes Bogers. Gelatine 48 gr Glycerine 8 gr Water 240 ml Two drops of essential oil Mix all the components at medium heat (60C) until smooth, then simmer at max 86C for 10-15 mins or more for less shrinkage, but be sure the liquid remains 'pourable'. It is also possible to boil the liquid at 100C for 5-10 mins. The process of boiling will change the polymer chains and make the cast material significantly harder, almost epoxy-like, and slightly more brittle. This recipe yields appr. 200 ml of material to be cast (depending on the amount of water that you let dissipate during the cooking process). Depending on the desired shape you have a few options;  1: For a thin, hard, 3d shape: Cast your bio-resin on a flat surface. De-mould your sheet of bioplastic when it is still flexible (often this is already possible after a few hours) and hang the sheet over some kind of mould or object. While drying it will slighty shrink and become hard in the shape you moulded it in. Keep ventilated until it is dry. 2: A hard solid shape: Cast in a shaped mould. Let the material dry in a ventilated and dry room and de-mould when your plastic feels solid, but still cold to the touch - often after 24-48 hours. Keep ventilated and regularly turn your piece over until it is dry. RECIPE #3: Bio Silicone This is the starting recipe for a silicone-like mixture, that is firm but flexible after drying and can be cast as a sheet or molded in a shape using a two-part mold. From here you can add even more glycerine to make the material more flexible, until 1:1 ratio, where you will only add a splash of water and slowly mix by heating. This recipe yields appr. 250 ml of material to be cast (depending on the amount of water that you let dissipate during the cooking process).  Image credit: Shirley Niemans. Gelatine 48 gr Glycerine 24 gr Water 240 ml Two drops of essential oil Mix the gelatine with the cold water in your pot, and stir until dissolved. Warm up the mixture on your stove to a max of 80C. Add your plasticizer and two drops of essential oil. The general rule is: the more glycerine, the more flexible the material, but do not exceed 1:1. Simmer for 15 minutes while stirring regularly, then let the liquid cool for a couple minutes while stirring, until it gels a little but is still liquid. The mixture should be at least honey-like before casting. Remove any froth with a spoon, or absorb it using a coffee filter or kitchen paper (cartouche). TIP: Longer cooking time (up to an hour) allows more water to evaporate and will dramatically reduce shrinkage of your casted object. You will get a thicker liquid. To cast larger volumes and solids with this recipe, evaporate a lot of water, until it's very very thick. Sometimes it's worth reheating and melting scraps, they've already dissipated a lot of water and result in nice castings. Optional: Add a filler and mix gently until it is evenly distributed throughout the liquid. Slowly, and while keeping the flow in one place to avoid air bubbles, pour the mixture in your mould or on your chosen surface. Note: Don't cast hot bioplastic on acryllic that is thinner than 7mm, it will bend. Drying / curing: Let the material dry in a ventilated and dry room and de-mould when your plastic feels solid, but still cold to the touch - often after 24-48 hours. Keep ventilated and regularly turn your piece over until it is dry, so as to avoid mold formation with long drying times. RECIPE #4: Bio Foam This recipe will result in a soft, flexible, foamy biomaterial. To create more or less flexibility, vary the amount of glycerine between 5 gr (brittle) and 60 gr (very flexible). Use a hand whisk or electric whisk to fiercely whip the air into the mixture before casting. Try out other frothing tools such as an electric milk foamer or even a regular straw to help you create and trap different-size air bubbles within the mixture.  Image credit: Shirley Niemans. Gelatine 12 gr Glycerine 12 gr Water 150 ml/gr Dishwashing soap (organic) or green soap 1 teaspoon (+/- 6 ml) Two drops of essential oil Mix the gelatine with the cold water in your pot, and stir until dissolved. Warm up the mixture on your stove to a max of 80C. Add your plasticizer and two drops of essential oil.  Simmer and slowly stir the mixture between 60-80 degrees Celcius for 20 minutes or until it's thick like a syrup or honey, then add in the soap Whisk vigorously to create foam bubbles and simmer for another 2-5 minutes until the mixture thickens. !! While whipping the mixture, the added air will make it solidify quickly. Be sure to keep your pan on medium heat to keep the mixture soft. Reheat if needed to melt it down again.  Stir slowly to let the bigger bubbles pop until you have a foam with small bubbles Cast onto a (textured) surface and spread out if necessary, or cast in a shallow mould. Casting foam goes best if you start casting in the center of the sheet / mould and allow the material to spread itself, keeping the pot still for even results.  The material will shrink a lot so make the layer thicker than you want the end result to be. Let it dry for 48-72 hours at least before releasing. Keep ventilated. RECIPE #5: Bio Foil (extra flexible) A transparent, glossy and very flexible sheet of gelatine-based bioplastic. Slightly sticky. This foil is thick and strong and completely transparent, a bit like the PVC table cloths. In the picture, roughly ground madder root was added to the mixture for color and texture, before casting.  Image credit: Shirley Niemans. Gelatine powder 24 gr Glycerine 18 gr Water 200 ml Two drops of essential oil Mix the gelatine with the cold water in your pot, and stir until dissolved. Warm up the mixture on your stove to a max of 80C. Add your plasticizer and two drops of essential oil. The general rule is: the more glycerine, the more flexible the material, but do not exceed 1:1. Simmer for 15 minutes while stirring regularly, then let the liquid cool for a couple minutes while stirring, until it gels a little but is still liquid. The mixture should be at least honey-like before casting. Remove any froth with a spoon, or absorb it using a coffee filter or kitchen paper (cartouche). TIP: Longer cooking time (up to an hour) allows more water to evaporate and will dramatically reduce shrinkage of your casted object. You will get a thicker liquid. To cast larger volumes and solids with this recipe, evaporate a lot of water, until it's very very thick. Sometimes it's worth reheating and melting scraps, they've already dissipated a lot of water and result in nice castings. Optional: Add a filler and mix gently until it is evenly distributed throughout the liquid. Slowly, and while keeping the flow in one place to avoid air bubbles, pour the mixture in your mould or on your chosen surface. Note: Don't cast hot bioplastic on acryllic that is thinner than 7mm, it will bend. Drying / curing: Let the material dry in a ventilated and dry room and de-mould when your plastic feels solid, but still cold to the touch - often after 24-48 hours. Keep ventilated and regularly turn your piece over until it is dry, so as to avoid mold formation with long drying times. Sources Lab Pastoe https://labpastoe.gitbook.io/lab-pastoe   Textile Academy: https://class.textile-academy.org/classes/2020-21/week06/#lecture-notes Loes Bogers: https://class.textile-academy.org/2020/loes.bogers/projects/outcomes/24_core_recipes/   Anastasia Pistofidou: https://issuu.com/nat_arc/docs/bioplastic_cook_book_3/s/159731   Agar bioplastic recipes Agar is a substance obtained from red algae. Agar bioplastic is made by mixing water, glycerine and agar powder. Together they form a foil-like plastic substitute that is flexible, but not elastic. Material properties: Water resistance: Agar bioplastics start dissolving after a couple of hours when submerged in room temperature water. It instantly melts when submerged in water of > 60C. Heat resistance: Agar bioplastics aren't heat resistant from 85C and up, the material will mutate. When microwaved, the material dissolves quite quickly. RECIPE #1: Flexible Agar Foil This recipe works best when cast in very thin foils. the foil will shrink and condense in size as well as thickness, but it will be strong and durable. Cook +/- 20-30 mins at appr. 80 degrees C. This recipe yields appr. 200 ml of material to be cast. Image credit: Loes Bogers. Agar 5 gr Glycerine 15 gr Water 250 ml Two drops of essential oil Warm up the water in the pot on your stove to a boil. If you want to dye your material in one colour, supplement (part of) the water with natural dye. Add your plasticizer. The general rule is: the more glycerine, the more flexible the material. When adding too much glycerine your material may remain sticky. Add the agar. Distributing the agar to the water/glycerol mixture slowly and evenly, while stirring gently will help it dissolve better, while avoiding the creation of bubbles. Mix gently until the ingredients form a smooth mix. Turn the heat down to about 70-80 degrees and let it simmer for about 20-40 minutes while stirring regularly. The mixture should be sirupy rather than watery before casting. A thicker mixture results in a thicker material, and it dries faster because more water has already evaporated. Optional #1: Add a filler and mix gently until it is evenly distributed throughout the liquid. Optional #2: If you are planning to make a batch of different colors, prepare your colors in a small container, to which you will add the liquid when it is ready to cast. Slowly, and while keeping the flow in one place to avoid air bubbles, pour the mixture in your mould or on your chosen surface. Drying / curing: Let the material dry in a ventilated and dry room and only de-mould when completely dry, to achieve the agar-like smooth finish. The agar bioplastic loses a lot of water and can therefore shrink up to 20%, depending on the water-agar ratio that was used. RECIPE #2: Agar Composite A composite of textile and agar foil. The composite feels less flexible and less rubbery than the agar foil.  Image credit: Shirley Niemans. Agar 5 gr Fabric 15x15 cm Glycerine 15 gr Water 250 ml Two molds that fit over each other Two drops of essential oil Warm up the water in the pot on your stove to a boil. If you want to dye your material in one colour, supplement (part of) the water with natural dye. Add your plasticizer. The general rule is: the more glycerine, the more flexible the material. When adding too much glycerine your material may remain sticky. Add the agar. Distributing the agar to the water/glycerol mixture slowly and evenly, while stirring gently will help it dissolve better, while avoiding the creation of bubbles. Mix gently until the ingredients form a smooth mix. Turn the heat down to about 70-80 degrees and let it simmer for about 20-40 minutes while stirring regularly. The mixture should be sirupy rather than watery. Dip the textile in the hot liquid, take it out and drape it over the mold, pressing it down with the second mold. After an hour, take the top mold off and let air dry (if possible, ventilated). RECIPE #3: Agar Spirulina Beeswax Bioplastic A fairly quick to make flexible and water resistant material, with a distinct green hue. The ph of the agar changes the hue of spirulina from blue-green to green.  Image credit: Materiom. Agar 25 gr Glycerine 30 ml Spirulina 2,5 gr Beeswax pellets 1 gr Water 500 ml Two drops of essential oil Mix agar and spirulina together in cold water. Heat up the mixture slowly and add the wax pellets. When the liquid reaches 50 degrees, add the glycerine. Stir and heat to just below boiling, then cast. Dry in a food dehydrator for 2 to 3 days at 30 degrees. Sources Lab Pastoe https://labpastoe.gitbook.io/lab-pastoe   Textile Academy: https://class.textile-academy.org/classes/2020-21/week06/#lecture-notes Loes Bogers: https://class.textile-academy.org/2020/loes.bogers/projects/outcomes/24_core_recipes/   Materiom open source materials library: https://commons.materiom.org/login   Starch bioplastic recipes Starch is a white, tasteless, and odorless carbohydrate that is found in large amounts in plants, e.g. grains, potatoes, and corn, where it serves as the chief energy storage form. Starch is insoluble in cold water and is used in foods and industry for thickening, stiffening, and energy production. TIP: You can easily extract your own starch from potatoes, cassave or rice. See e.g. this recipe . Material properties: Water resistance: Starch bioplastics tend to absorb moisture easily and have high water vapor permeability; their hydrophilic nature limits their performance in wet conditions unless additives or treatments are used. Heat resistance: Pure starch bioplastics can withstand moderate temperatures but generally exhibit poor heat resistance compared to conventional plastics; performance can be improved with mineral fillers such as clay or chalk, but they often deform or degrade at temperatures above 65C. RECIPE #1: Flexible Corn Starch Foil This recipe works best when cast in very thin foils. the foil will shrink and condense in size as well as thickness, but it will be strong and durable. This recipe yields appr. 250 ml of material to be cast. Image credit: Tiare Ribeaux. Corn starch 30 gr White vinegar 60 gr Glycerine 50 gr Water 400 ml Two drops of essential oil Prepare your casting surface or frame and measure out ingredients, and if you want the fillers and pigments. If you use natural dye, substitute part of the water amount with the dye. Mix the main ingredients together until it is a homogenous mix. Feel free to try out different ratios - less starch makes the solution less thick and less glycerol makes it less flexible. Optional: Add pigment or fillers in this phase, later the mixture may be too thick to distribute evenly. Cook over medium heat and stir well for 10 minutes or longer - continue to heat even after solution is sirupy or viscous to dissipate more water and avoid shrinkage. After 10 minutes, or when large bubbles start appearing, bring it down to low heat. The mixture should be semi-transparent and paste-like by now. Remove from heat for 30-60 seconds and get ready to spoon out almost immediately Spoon a thin layer of mixture into a frame to create a thin, even surface, or cast and spread on a larger flat surface to create a spread out film. The thicker the layer, the more the starch bioplastic is prone to crack, so create as thin of a layer as possible - a silicone baking sheet gives the best, most even results. If your mixture is very thick, you can flatten it between folded parchment paper or silicone sheet, by pressing it with a heavy book or roller. Drying / curing: Let the material dry in a ventilated and dry room. If you used a frame, cut the edge of the starch bioplastic loose after 24 hours, to prevent it from breaking in the middle. If you have a thicker layer and you need it to be flat, consider pressing and drying every few hours alternatively. Let the material sit and let dry for at least three days, remove from the surface when it is no longer cold to the touch. RECIPE #2: Walnut Potato Starch Composite !! One or two days before getting started with this recipe, you need to prepare the walnut shells. Wash them with water and dry them for two days in the open air, or one day in the food dehydrator at the lab. Then crush in an electric grinder and sieve according to the size of grains you want. In this example, grains are larger than 0.3 mm.  Image credit: Materiom. Potato starch 15 gr walnut shells 250 gr Vinegar 7,5 ml Glycerine 7,5 ml Water 60 ml Prepare your casting surface or frame and measure out ingredients, and if you want the fillers and pigments. If you use natural dye, substitute part of the water amount with the dye. Mix the main ingredients together until it is a homogenous mix. Feel free to try out different ratios - less starch makes the solution less thick and less glycerol makes it less flexible. Optional: Add pigment or fillers in this phase, later the mixture may be too thick to distribute evenly. Cook over medium heat and stir well for 10 minutes or longer - continue to heat even after solution is sirupy or viscous to dissipate more water and avoid shrinkage. After 10 minutes, or when large bubbles start appearing, bring it down to low heat. The mixture should be semi-transparent and paste-like by now. Add the walnut shells to the mixture. Spoon the mixture in a mold, wait for it to dry to unmold, then put it in a dehydrator for 8 hours at 40 degrees Celsius. TIP: You can use many other fillers aside from walnut, such as sawdust, cork particles or clay powder.  RECIPE #3: Starch and Gelatine-based Rubber A rubbery bioplastic based on gelatin and potato starch. It's strong but flexible and is less stiff than the gelatine-based biosilicone for example. It has a sour smell from the vinegar, which slowly fades but does not disappear completely.  Image credit: Loes Bogers. Potato starch 50 gr Gelatine powder 50 gr White vinegar 15 gr Glycerine 100 gr Water 100 ml + a bit Add gelatine and glycerine to boiling water. Keep temp above 80 degrees, and stir very gently with a spoon until it is dissolved. Dissolve the starch with vinigar in a separate bowl using a few tablespoons of hot water . Only when the gelatine is completely dissolved, add the starch mixture and stir for another 5-10 mins at 80 degrees until you have a thick but somewhat liquid paste. Use a spatula to smear the paste on the surface or in the mold. Unmold after 24-48 hours and alternately dry and press to keep flat (if that is wanted).  Sources Lab Pastoe https://labpastoe.gitbook.io/lab-pastoe   Loes Bogers: https://class.textile-academy.org/2020/loes.bogers/projects/outcomes/24_core_recipes/   Anastasia Pistofidou: https://issuu.com/nat_arc/docs/bioplastic_cook_book_3/s/159731   Materiom: https://materiom.org Alginate bioplastic recipes Sodium Alginate is extracted from brown seaweed. Alginate bioplastics are made by combining sodium alginate, glycerine and water with the curing agent calcium chloride, and are heat/water resistant! Material properties: Water resistance: Alginate bioplastic, once dipped in calcium chloride, is waterproof for PH neutral or acid water. It starts dissolving in a couple of hours when the PH of the water is alkaline. Heat resistance: Alginate bioplastic is very heat resistant, even when cast in a thin sheet it can withstand temperatures up to 150 degrees Celsius. RECIPE #1: Alginate Foil An alginate based, heat-resistant and waterproof semi-transparent, matte foil. The foil has a feel that can be compared with a window foil (to blind windows but let the light through). It's matte but very translucent. Image credit: Loes Bogers. Sodium alginate powder 12 gr Glycerine 20 gr Water 400 ml Sunflower oil 10 gr (optional) Calcium chloride solution 10% (10 gr to 100 gr water) Mix the alginate with water and glycerine. The best way to get a smooth mixture is to use a hand-held mixer or blender. If you are planning to make a batch of multiple colors, prepare your colors in a jar or small containers, to which you will add the mixture. This recipe uses sunflower oil as a filler to reduce shrinkage. Note that it will also make the resulting material slightly yellowish and opaque, leaving it out will render a bit more crispy and translucent foil. Add the sunflower oil to the blender and mix well. Once the mixture is smooth and completely dissolved, let it sit for several hours or overnight - this will allow all the bubbles to leave the mixture. Prepare a solution of water and calcium chloride, at 10%, and fill a small spray bottle with it. Prepare your surfaces and molds by spraying the calcium chloride solution on them. Anything you cast on should be waterproof so the calcium chloride solution will not be absorbed. Cast the alginate mixture onto the surface or mold. Once you start pouring, try to cast slowly and onto the mixture itself, so as not to encapsulate air. Spread the material to a thin film using a wide spatula, a ruler, or by moving the mold around. You can also use a spatula or squeegy to push the material in the shape and thickness that you want it. After a couple of minutes, spray the alginate with the calcium chloride mixture. Let it sit for a few minutes, then spray again if you see the liquid is starting to ooze out from the sides. The film that is created in the curing process can break from the weight of the liquid bubble. By respraying you can close these until the sheet is cured enough and stable to dry further. The alginate can release quite a lot of water at this stage, so it's wise to place some kitchen paper around it to absorb excess water. The cast materials will shrink both in thickness and width. Drying / curing: Keep an eye on the material every few hours, especially on the first day. The thinner edges of a sheet might curl up when drying and pull off parts of the sheet. When it comes loose it will start to warp. Taping the edges down onto the surface you use helps to keep it in place and dry in the shape you want. Let it dry up to seven days to get to the final form. When it no longer feels cool to the touch it is dry enough to take off. If you want to trim the edges do it while the foil is still a bit softer for a clean cut. RECIPE #2: Oyster shell Alginate Composite This recipe creates a firm paste that can be extruded using e.g. a clay printer or a large syringe / kit syringe.  Image credit: Markos Georgiou. Sodium alginate powder 0,7 % Honey 4% Water 27,3 % Oyster shells 68% Calcium chloride solution 10% (10 gr to 100 gr water) Collect your shells from local waste streams (restaurants or fish mongers. Wash and clean the oyster shells from any remains and boil them for 30 minutes. Then bake the shells for 45 minutes at 180°C to make them more fragile. Using a dish cloth on top, smash the shells into smaller pieces with a hammer. Place the pieces in the oven again for another 45 minutes at 200°C. It will make them more brittle and easier to grind. In a blender or a mortar, grind the shells into the finest powder possible. Sieve the ground shells to obtain the smallest particle size (in this example: 40 micron). To create the alginate solution (binder), add Sodium Alginate powder ( 2.5% of total weight) and Water ( 97.5% of total weight). Stir well until a gel is formed and let sit for at least 3 hours. Measure the desired amount of oyster shell powder. Add binder to the powder until the right ratio is met. The powder : binder ratio is 1 : 0,4. Measure the total weight of the mixture and add 5% honey. Stir well until all dry powder is wet and homogenous. For the extrusion in this project, the material was printed with a biogun but you can also use a large syringe. RECIPE #3: Orange peel, Wool & Alginate bioplastic The video shows the recipe for creating a sewable leather alternative using alginate, orange peel and wool.  Video credit: Fab Lab Barcelona. Sources Lab Pastoe https://labpastoe.gitbook.io/lab-pastoe   Fablab Barcelona, REMIX EL BARRIO  Making bioplastic from Orange peel Loes Bogers: https://class.textile-academy.org/2020/loes.bogers/projects/outcomes/24_core_recipes/   Materiom open source materials library:  https://commons.materiom.org/login