Starch extracted artisanally from the avocado pit, seed of Persea americana.
1• In a bowl put 200 ml of preboiled cold water (more or less depending on how much avocado pit you are going to grate).
2• Grate the avocado pit with a manual metalic grater over the water. The avocado pit in contact with the metal and the air (oxidation) will start generating this impresive orange color due to the tannins present in the avocado pit. 3-4 medium size avocado pit will do.
3• Wait until the water turn orange and the starch slowly decant at the bottom.
4• Stir every once in a while to remove starch from the grated pit. (30 min)
5• Put a dish cloth over a tall glass and push it inside so it will work as a strainer. Pour the mixture over and wait until all the liquid passes through. Then take the leftover and the dish cloth and twist squeezing the leftover liquid and starch through the textile. Use a loose textile, if not the starch will accumulate in the cloth and will not pass through with the liquid. Depending on how opaque you want your bioplastic you can also do this with a strainer.
6• Reserve the avocado pit leftover for a biocomposite.
7• In the tall glass the wait till the starch decant totally and the liquid is furious orange and clear.
8• Extract the liquid just tilting the glass carefully so the starch does not move, and reserve for the bioplastic.
9• At the bottom of the glass you'll have the starch. Wait for a day to dry and become a powder. This is very important to be able to measure it for the bioplastic.
Persea americana seed. Agroindustrial and household waste.