Fermentation

Fermentation

  January 24, 2013    Unknown

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Introduction

Beer and wine are produced by the fermentation of glucose by yeast. In this experiment, a glucose solution is left to ferment. The resulting mixture, is then tested for the presence of any fermentation products.

Apparatus

Boiling tube, Conical Flask, Delivery tube for boiling tube & conical flask, Yeast Powder, Lime Water, 10% Glucose solution

What to record

What was seen to happen to the limewater.

What to do

Lesson 1

1. Put 5 g of glucose in the flask and dissolve it in 50 cm3 of warm water. (Becomes 10% Glucose Solution)
2. Add 1 g of yeast to the glucose solution and plug the top with delivery tube.
3. Wait 20 min while fermentation takes place.
4. Remove the delivery tube and pour the invisible gas from the flask into the boiling tube with lime water. Take care not to pour any of the liquid as well.
5. Gently swirl the lime water round the tube and observe what happens.

Lesson 2

1. Note the smell of the solution.

Safety

Wear eye protection. Do not taste the product.

Questions

1. What gas is present in the flask after fermentation?
2. Yeast contains a chemical called zymase, which is an enzyme. Complete the word equation for fermentation.

             zymase

Glucose ------------>              +