Hydrocolloids are just too cool for school. Also their usefulness for 3D food printing is just too obvious to overlook it 🙂
Recommended percentage go from 0.5 to 2%.
For our tests we used 111gr of water and 1.87gr of agar agar.
First we dispersed the agar agar into cold water, to avoid clumps later, stirring it. Later we bring it to a boil.
After that is just a matter of cool it down until it forms a gel.
The result is a brittle but strong gel. It took around 20minutes to set at 18ºC room temperature. Pumping it with a syringe into small dots sets it pretty fast (less than a minute). And that just means one thing. It is perfect for printing purposes.
Good or bad, depending on your printing method, agar is quite fluid before setting. This makes it harder to control with air compressed (our system has problem handling under 1psi pressure), but maybe easier for a peristaltic pump.
Setting time is fast, what is extremely good, but requires a heating system to avoid clogging the nozzle.