Chitosan is a hydrocolloid made from Chitin. Chitin is one of the most common biomolecules on earth. It is the main structural component of arthropod exoskeletons and fungal cell walls. Most Chitosan used for wine fining comes from shrimp shells. Even though shrimp-derived chitosan is non-allergenic, many people prefer a vegan alternative. This vegan Chitosan comes from the fungus Aspergillus Niger. Chitosan is insoluble in pure water, so you have to make a solution with dilute acid (vinegar).
Chitosan is often used in conjunction with other fining agents, such as Kieselsol.
To make Chitosan solution:
Add 400 ml water to a blender. Turn the blender on to a low to medium speed to create a vortex. Add 5 grams Chitosan powder to the vortex. Try to add the powder to the spinning liquid without hitting the sides of the blender pitcher. This step disperses the Chitosan. Add 100 ml 5% distilled vinegar (this is the normal one sold in US supermarkets –the percent acidity is listed on the label). Blend for several minutes till the Chitosan is completely dissolved. Note: Don’t blend on high speed in a Vita-mix or similar high-speed blender too long or you will heat the mixture and boil off some of the vinegar.
Refrigerate your Chitosan Solution. It should last several months.
For use in Spinzall:
Most liquids products need to be pre-treated with clarifying aids in order to work in the Spinzall. If the enzyme pre-treatment (using Pectinex Ultra-SPL) is adequate, you will see a “break:” cloudy patches separated by areas of obviously clear liquid. If you see this break, you are ready to spin. Note: you may see a break in as little as five minutes. If you do not see a break, you may need to additionally treat your product with the wine fining agent Chitosan and Kieselsol. Chitosan and Kieselsol work by making the solids in your product clump together into larger particles that are easier for the Spinzall to spin out.
First add two milliliters of Kieselsol per liter of product, stir, and wait 15 minutes. Then add two milliliters of Chitosan per liter of product, stir, and wait 15 minutes. Finally add two more milliliters of Kieselsol per liter of product, stir, and wait as long as you wish. The longer you wait, the harder the product will break and the easier it will be to clarify. You can remember this recipe as “ Two-Fifteen” because all the measurements are 2 milliliters and you are always waiting 15 minutes.
Per liter of product:
- Add 2ml Pectinex Ultra-SPL and 2ml Kieselsol
- Wait 15 minutes
- Add 2ml Chitosan
- Wait 15 minutes
- Add 2ml Kieselsol
- Wait 15 minutes or longer, then spin