How to Find the Level of Ascorbic Acid in Plants

Measure 1 tsp. of cornstarch into a heatproof container. Add just a few drops of water and stir until the cornstarch makes a paste. Add 1 cup of water and heat for two minutes in a microwave to dissolve the cornstarch in the water. Set it aside to cool.

Blend a measured amount of the plant you want to measure with an equal part of water. Blend until you have liquefied the plant material. Strain the liquid through a cheesecloth. Repeat for any other plants you want to test for ascorbic acid levels. Pour 1 oz. of each of the plant liquids into separate paper cups, using a measuring cup.

Add 10 drops of the cooled starch mixture to each cup in your experiment. Stir each of the cups with a separate plastic coffee stirrer.

Slowly drip iodine into the first cup, counting each drip and stirring after each drip. The iodine will change to a blue when it touches the starch, but any ascorbic acid present will change the color. Keep dripping in the iodine until the color changes back to a dark color that does not change after 10 seconds. Repeat for the other plants.

Calculate the amount of iodine necessary to change the color of the mixtures and then use that as an indicator of how much ascorbic acid was present. The more iodine needed, the higher the level of ascorbic acid. Compare the results between the plants to determine which has the highest level of ascorbic acid.

Compare the results with a test sample of orange juice, known to be high in ascorbic acid, for an idea of how the levels relate to other foods.