We didn't get to this activity in class, but it is easy enough to do at home.
1. Draw a simple blank map of the tongue
2. Swab the blue food coloring on the front of the tongue (cover the tip and about 1/2 inch back). Have the subject move the tongue around in the mouth and swallow. This distributes the dye. Swallowing the dye is not hazardous. You will see pink circles emerge from the blue background. The pink circles are the fungiform papillae. The fungiform papillae appear pink because they do not stain.
3. Now use a hole-punched cards to take 4 or 5 samples from your partner’s tongue. Count how many papillae you find in the circle. Map these areas on your tongue drawing. What is the average number of papillae per sample?
Supertasters have an average of over 30 papillae hole punch.