Vernier Software & Technology

# Sugar Fermentation by Yeast

## Introduction

Yeast can metabolize sugar in two ways, aerobically, with the aid of oxygen, or anaerobically, without oxygen. When yeast metabolizes a sugar under anaerobic conditions, ethanol (CH3CH2OH) and carbon dioxide (CO2) gas are produced. An equation for the fermentation of the simple sugar glucose (C6H12O6) is:

${{\text{C}}_{\text{6}}}{{\text{H}}_{{\text{12}}}}{{\text{O}}_{\text{6}}} \to {\text{2 C}}{{\text{H}}_{\text{3}}}{\text{C}}{{\text{H}}_{\text{2}}}{\text{OH + 2 C}}{{\text{O}}_{\text{2}}}{\text{ + energy}}$

The metabolic activity of yeast can be determined by the measurement of gas pressure inside the fermentation vessel.

## Objectives

In the Preliminary Activity, you will use a Gas Pressure Sensor to monitor the pressure inside a test tube as yeast metabolizes glucose anaerobically. When data collection is complete, you will perform a linear fit on the resultant graph to determine the fermentation rate.

After completing the Preliminary Activity, you will first use reference sources to find out more about sugar fermentation by yeast before you choose and investigate a researchable question dealing with fermentation.

## Sensors and Equipment

This investigation features the following Vernier sensors and equipment.

### Option 2

You may also need an interface and software for data collection. What do I need for data collection?

## Investigating Chemistry through Inquiry

See other experiments from the lab book.

 1 Physical Properties of Water 2 Baking Soda and Vinegar Investigations 3 An Investigation of Urea-Containing Cold Packs 4 Conductivity of Aqueous Solutions 5 Identifying a Pure Substance 6 Investigating the Energy Content of Foods 7 Investigating the Energy Content of Fuels 8 Evaporation and Intermolecular Attractions 9 Enthalpy Changes 10 Reaction Stoichiometry 11 Beer's Law Investigations 12 Colligative Properties of Solutions 13 Long Term Water Monitoring 14 Vapor Pressure and Heat of Vaporization Investigations 15 Acid-Base Properties of Household Products 16 The Effect of Acid Deposition on Aqueous Systems 17 Acid-Base Titrations 18 Conductimetric Titrations 19 Oxidation-Reduction Titrations 20 Investigating Voltaic Cells 21 Baking Soda and Vinegar Investigations Revisited 22 Reaction Rates 23 Enzyme Activity 24 Sugar Fermentation by Yeast 25 Nuclear Radiation

### Investigation 24 from Investigating Chemistry through Inquiry Lab Book

#### Included in the Lab Book

Vernier lab books include word-processing files of the student instructions, essential teacher information, suggested answers, sample data and graphs, and more.