If you blend 10 mL of canola oil, 90 mL of water, .25 g of xanthan gum, .2 g of whey concentrate, and yellow food coloring for 20 seconds then it will create an emulsion that will last longer than 15 minutes.
An emulsion is the combination of two or more unlike substances that are not usually mixed together. For example, oil and water. When an emulsion is shook the ingredients will combine and in a short amount of time, separate. The amount of time it takes for the emulsion to separate differs depending on the ingredients, how they were mixed and the temperature of the emulsion.
Emulsions work by creating surface tension. When two molecules do not freely mix they sort themselves so that they will interact as little as possible. There are two phases to any emulsification. The continuous and dispersed phase. The continuous can be thought of as the “container” and it is what the other liquid will be “dispersed” into. Adding more continuous phase will thin an emulsion and adding more of the dispersed phase will thicken it. How you combine these unlike liquids is called shearing power. This is what is known as shaking, blending, stirring, etc. Shearing power is necessary to fully combine the liquids. The more shearing power used will shorten the dispersed phase causing a more stable emulsion (Burton).
An emulsifier is also used to create a stable emulsion. It works by keeping the oil molecules from coming together and separating from the water. Without an emulsifier the oil droplets will come together and separate from the water. Then the oil will form a layer that will float to the top of the surface of the water. When an emulsifier is used it will coat the oil droplets and allow them to stay mixed in with the water. An emulsifier stops the oil from clumping together and prevents the oil layer on top of the water (“Emulsifier”).
• 10 mL canola oil
• 90 mL water
• .25g xanthan gum
• .2g whey concentrate
• 100 mL graduated cylinder
• 10 mL graduated cylinder
• Yellow food coloring
• 1 capped jar
• Electronic balance
• Weigh boat
• Styrofoam cup
1. Measure out 90 mL of tap water and 10 mL of canola oil
2. Pour both into capped jar
3. Weigh .25g of xanthan gum and .2g of whey concentrate
4. Pour both into capped jar
5. Add two drops of yellow food coloring
6. Pour into blender
7. Blend for 20 seconds on whipped
8. Immediately pour into a 100 mL graduated cylinder
9. Start stopwatch
10. Record every mL that the emulsion separates
11. If the emulsion separates past 3 mL stop the stopwatch and record time
Results for Emulsion Challenge:
The emulsion listed above took 900 seconds to destabilize. The emulsion tied with the rest of the class, (except groups 13 and 14) for the longest destabilization time and was awarded 28 points. Group 14 was awarded 27 points for the second longest time and group 13 was awarded 26 points for the shortest time.