Unit 6 Lab: Fermentation Name__________________ Date_________

Yeast are natural fermenters. They break down sugars, without requiring oxygen, to yield alcohol and carbonic gas (CO2). Each group will prepare one of the situations below.

In each situation, all ingredients are placed in a small plastic bag and mixed, the bag is sealed, and placed in a warm place for 15 minutes.

Situation 1: 1 teaspoon of yeast, ¼ cup of water, 2 packets of sugar

Situation 2: 1 teaspoon of yeast, ¼ cup of water, 2 packets of sweet-n-low

Situation 3: 1 teaspoon of yeast, ¼ cup of water, 2 packets of truvia

Situation 4: 1 teaspoon of yeast, ¼ cup of water, 2 packets of splenda

Situation 5: 1 teaspoon of yeast, ¼ cup of water, 2 teaspoons of flour

Situation 6: 1 teaspoon of yeast, ¼ cup of water, 2 teaspoons of cornstarch

Question 1: What do you expect to happen in each situation? (Will fermentation occur? What would be the visible effect?)

Question 2: Sweet-n-low, Truvia, and splenda are all sugar substitutes. Would you expect them to have the same results as sugar or not? Why/why not?

Question 3: When performing an experiment, it is important to consider a positive an negative control. Do the situations outlined above have a positive control? A negative control? If so, which situation(s). If not, what would be an appropriate mixture?

Please turn in your predictions and observations for the situation tested by your group along with your answers to the three lab questions.