How are the color pigments in Skittles and M&Ms different?
Students will be able to determine what pigments are present in Skittles and M&Ms.
- 2 green Skittles
- 2 green M&Ms
- Aluminum foil
- Toothpicks Candy Chromatography 3
- 2+ coffee filters
- 2 tall clear cups
- Cut the filter paper into strips that measure 6cm x 8 cm with straight edges.
- Using a pencil, write M&Ms on one strip and Skittles on the other.
- At the bottom of each strip, use a ruler to find the point 1 cm from the bottom of the paper. Make pencil dots at 2cm and 4 cm across.
- Study the color of the green Skittle and the green M&M. Record observations and make predictions.
- Cut out 2 small pieces of foil.
- Place 2 separate dots of water on top of each of the pieces of foil.
- Place a green M&M on each drop on one piece of foil.
- Place a green Skittle on each drop on the other piece of foil.
- Wait a minute for the candy color to seep into the water.
- Dip a toothpick into the pool of green M&M dye. Touch it just above where you made a pencil dot at 2cm on the filter strip labeled M&M.
- Dab another dot at the 4cm on the same green M&M filter paper.
- Using another toothpick, dip into the pool of green Skittle dye. Touch it just above where you made a pencil dot at 2cm on the filter strip labeled Skittles. Candy Chromatography 4
- Dab another dot at the 4cm on the same green Skittle filter paper.
- Let the dots dry. This should take a minute or so.
- Repeat steps #10-14 at least 4 times to saturate the color, allowing it to dry between each application.
- While you are waiting, taste the green M&M and green Skittle does the green color taste the same in both candies?
- Make a salt-water solution by combining 3 cups of water with 1/8 tsp of salt.
- Pour some salt solution into each of your glasses about 1 cm deep.
- Hang each of your filter papers so it is just touching the edge of the water. Tape it in place to the side of the glass.
- When you see the wet layer of salt water has travelled up ½ cm from the top of the strip, remove it from the liquid.
- Set the strips on a clean, flat dry surface to dry.
- Observe the strips. Try to match the bands you see to the dye colors on the candy wrappers. Measure and record the distance each dye travelled.
- You should expect to see yellow green and blue dyes on the strips. The Skittle should show more yellow prominence and M&M should show more blue prominence