Level C - You're the Chef

Kitchen Talk Solutions

Bite 3 - Food Safety and Science


3a. Slow them down
Project skill: Demonstrating the action of preservatives
Life skill: Using scientific methods

2. Which solution became the cloudiest?
The control.

3. Why did the cups containing the preservatives never become as cloudy as the control?
Preservatives (such as vinegar and salt in large quantities) inhibit or slow down the growth of bacteria. Vinegar inhibited bacterial growth the best.


3b. Emulsions
Project skill: Making a frozen emulsion
Life skill: Using scientific methods

2. What is the emulsifier in this experiment?
The emulsifier in this experiment is the unflavored gelatin. When adding the whipping cream to the mixture, the gelatin in the variable bowl keeps the cream from separating from the water.

3. What is the role of an emulsifier when making brownies? Cookies?
When making brownies, the emulsifier, which is the egg, keeps the water from separating from the oil. Also, when making cookies, the emulsifier, also the egg, keeps the water from separating from the oil.


3c. Spoilers or helpers?
Project skill: Understanding the action of yeast
Life skill: Processing information

1. Which banana slice showed the fastest and most decomposition?
Banana treated with yeast.

2. How do the yeast and no-yeast slices differ from each other?
The yeast feeding on the banana caused it to break down into smaller parts; it decayed. (In this instance, yeast acts as a decomposer, breaking down food so other organisms can use it.) The untreated banana slice has darkened because it was exposed to air, but it is not decomposing.

3. If yeast is not activated in bread making, how will the final product be affected?
If yeast is not activated, the bread dough will not rise.


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