Science Buddies: "Ask an Expert"

I'm having trouble figuring out what the control would be for this experiment. Since we are using apple juice and adding different colors, I think that if we just have plain apple juice as the control would clue the students on what they were drinking which would skew the information. Can you help?


[Administrator: link to project: https://www.sciencebuddies.org/science- ... fect-taste ]