Citric acid provides the tanginess in drinks, candy and fruit. By making citric acid, you can sprinkle it in any recipe to give it a little punch. Citric acid is also used to preserve juice and other foods. In Hawaii, citric acid powder is used to control Caribbean tree frogs. Citric acid is plentiful in lemons, limes and grapefruit. It can be exacted at your home and store in powder form.
Measure one cup of lime juice. Pour the juice into a cooking pot. Lime or grapefruit juice can be substituted for lime juice.
Add one tspn. of calcium hydroxide into the cooking pot.
Pour the heated solution into a glass container. Place the glass container in a large bowl. Surround outside of the glass container with ice. Cool the solution for 20 minutes.
Pour the cooled solution into a coffee filter. The filter traps calcium citrate. Calcium citrate is converted to citric acid.
Remove the calcium citrate particles from the inside of the coffee filter using a spoon. Weigh the particles on a digital scale. Continue this process until there are 50 grams of particles.
Place the powder in an oven-safe container. Squeeze 35 grams of sulfuric acid into the container using an eye dropper.
Preheat the oven to 150F. Put the container in the oven for five minutes.
Remove out the solution. Stir the solution with a metal spoon. Put the container back into the oven for five minutes.
Remove the solution. Cool the solution for 30 minutes. The liquid will evaporate. Citric acid powder remains. If the citric acid is chunky, crush the citric acid with the back of a spoon to make powder
Protective goggles, gloves, mask and clothing should be worn during the whole process. The chemicals used should not make direct contact with your skin.