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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