Science Buddies: "Ask an Expert"

My project is on candy chromatography. My question for my experiment is "What dyes are used in the coatings of skittles?" I cannot think of a hypothesis for this experiment to answer my question and I could really use some help. I have already tried looking over the experiment and going to the science buddies page on how to write a hypothesis. Any ideas? Thank you for your help!

Hi,
Welcome to Science Buddies!

If you haven't already done so, please check out the science buddies page on "Color Chromatography: What makes those colors?" This page gives you a full overview from the introduction to the experiment procedure.
https://www.sciencebuddies.org/science- ... p006.shtml

If you have additional questions, please feel free to ask
-Grace

In addition to Grace's reply, I can suggest a few hypotheses to get you thinking: All manufacturers use the same dyes to get the same colors. Multiple dyes are always used to achieve a given final color. Primary colors use single dyes. All colors are achieved with a single dye. Single dyes are used more often than multiple dyes.

Hope that helps.

Hi, Lexxe15,

It is helpful to know that the seven main food colorings in the United States approved by the Food and Drug Administration (FDA) are FD&C Blue No. 1 (“Brilliant Blue” FCF, E133), FD&C Blue No. 2 (“Indigotine”, E132), FD&C Green No. 3 (“Fast Green” FCF, E143, the least used), FD&C Red No. 40 (“Allura Red” AC, E129), FD&C Red No. 3 (“Erythrosine”, E127), FD&C Yellow No. 5 (“Tartrazine”, E102), and FD&C Yellow No. 6 (“Sunset Yellow” FCF, E110), where FD&C stands for Food, Drug, and Cosmetics.

Chances are, Skittles has most of the above, if not all. And according to a Skittles wrapper, the food coloring for all candies in the original series (red, yellow, orange, green, and purple) includes Yellow 6 Lake, Red 40 Lake, Yellow 5 Lake, Blue 2 Lake, Yellow No. 5, Red No. 40, Yellow No. 6, Blue 1 Lake, and Blue No. 1. This information should help you create a hypothesis, although you might want to change the question a little bit. Perhaps you could ask which dye is most prominent or yields the largest Rf value (distance traveled by a band/distance traveled by the solvent) for a colored band on the chromatogram.

Hope this helped,
RM