Feedstock Fermentation
Participants conduct an experiment on fermentation to learn how biofuels are created!
This workshop discusses topics which can lead to feelings of eco-anxiety among volunteers, educators and youth if not presented in a thoughtful manner. The most important things to remember are to be honest, hopeful, developmentally appropriate, and action oriented. This workshop was created with these guidelines in mind. For more details, refer to the volunteer resource, Being Conscious of Eco-Anxiety.
What You Need
Materials
- Snack-sized plastic baggies, labelled
- Dry active yeast
- Warm water
- Measuring utensils
- Paper towels
- Feedstocks such as:
- White sugar
- Corn meal
- Sawdust
- Dry ground grass clippings or leaves
- Ruler
- Label and writing utensil
Guide:
Safety Notes
Monitor the bags and remove some air if they become too inflated.
What To Do
- Introduce the concept of biofuels and how they are made. Adjust the discussion based on the participants age and prior knowledge.
Biofuels are fuels that are made from plant and animal waste. Biofuels are classified by the raw material that is used to create them, called feedstocks. There are two main types of biofuels: ethanol and biodiesel. Ethanol is made from plants and biodiesel is made from vegetable oils or animal fats.
Ethanol is made by breaking down the starch from crops, like corn, into sugars. Microorganisms, called yeasts, break down simple sugars into ethanol using a process called fermentation, releasing carbon dioxide. In Canada, ethanol is mixed with gasoline to produce a more environmentally friendly fuel.
Today we are going to do a fermentation experiment using different feedstocks to see which one would be the best to make our own biofuel!
Activity
- Separate participants into small groups. Give each group a set of supplies.
- Instruct participants to label each bag (1 per feedstock).
- They will add 1 teaspoon of feedstock and 1 teaspoon of yeast to each bag.
- They will Add 50 ml (1/4 cup) of warm water to each bag.
- Have participants seal the bag and try to remove as much air as possible and gently squeeze the bag to mix.
- Lay the bags on a flat surface. Let it process for approximately 15 minutes.
- Have the participants use a ruler to measure the height of each bag.
- Compare the results of the different feedstocks. Which feedstock would be the best to use for our biofuel? Why?
Wrap-Up
- Discuss how utilizing biofuels and other forms of green energy reduces greenhouse gas emissions and is important for the planet.
- Discuss possible careers and what participants will need (schooling, experience, etc…) to get into those careers.
Discovery
Fermentation is a process that has been used for hundreds of years to produce many things, like bread, wine and cheese. During fermentation, microorganisms, such as yeasts, bacteria and fungi (molds) break down simple sugars to produce ethanol. Fermentation also is used in creating pharmaceuticals, such as antibiotics like penicillin!
In this activity, the yeast breaks down the white sugar the most efficiently, which is why the bag inflates the fastest with carbon dioxide. The other feedstocks are not as refined (or processed) as the white sugar, meaning that it is harder for the yeasts to break down the sugars. This is why the bags take longer to inflate or do not inflate at all.
Biofuels are considered a source of green energy because they do not produce greenhouse gases. Greenhouse gases trap heat from the sun, like a blanket around the Earth. We need some greenhouse gases to keep the Earth warm enough for living things, but human activity, like burning fossil fuels (oil, gas, coal), is adding too many greenhouse gases into the atmosphere. This causes the Earth to warm up faster than it should, resulting in changes in weather and precipitation patterns (climate change).
Biofuels release greenhouse gases when they are burned, but they are considered carbon neutral because the plants absorb carbon dioxide (a greenhouse gas) for photosynthesis. By using biofuels, we reduce the amount of greenhouse gases released into the atmosphere and our dependence on fossil fuels!
- Zooshare is Canada’s 1st Zoo Biogas Plant that turns poo from the Toronto Zoo and inedible food waste into renewable power. Learn more about Zooshare and discuss possibilities for other places or sources of waste that could be used to produce biofuel.
- There are four different categories or generations of biofuels. Ethanol, from crops like corn, is considered a first-generation biofuel. Second generation biofuels are made from non-food sources like wood, straw and crop waste. Third generation biofuels are produced by algae that produce oil. Fourth generation biofuels are made from genetically modified algae.
- Do more research and discuss the pros and cons of the different methods of producing biofuels. Consider what resources are required to produce/grow the feedstock. Which biofuel sounds like the most sustainable option? Have participants share their thoughts in a Pros & Cons Organizer.
What's Happening?
Fermentation is a process that has been used for hundreds of years to produce many things, like bread, wine and cheese. During fermentation, microorganisms, such as yeasts, bacteria and fungi (molds) break down simple sugars to produce ethanol. Fermentation also is used in creating pharmaceuticals, such as antibiotics like penicillin!
In this activity, the yeast breaks down the white sugar the most efficiently, which is why the bag inflates the fastest with carbon dioxide. The other feedstocks are not as refined (or processed) as the white sugar, meaning that it is harder for the yeasts to break down the sugars. This is why the bags take longer to inflate or do not inflate at all.
Why Does it Matter?
Biofuels are considered a source of green energy because they do not produce greenhouse gases. Greenhouse gases trap heat from the sun, like a blanket around the Earth. We need some greenhouse gases to keep the Earth warm enough for living things, but human activity, like burning fossil fuels (oil, gas, coal), is adding too many greenhouse gases into the atmosphere. This causes the Earth to warm up faster than it should, resulting in changes in weather and precipitation patterns (climate change).
Biofuels release greenhouse gases when they are burned, but they are considered carbon neutral because the plants absorb carbon dioxide (a greenhouse gas) for photosynthesis. By using biofuels, we reduce the amount of greenhouse gases released into the atmosphere and our dependence on fossil fuels!
Investigate Further
- Zooshare is Canada’s 1st Zoo Biogas Plant that turns poo from the Toronto Zoo and inedible food waste into renewable power. Learn more about Zooshare and discuss possibilities for other places or sources of waste that could be used to produce biofuel.
- There are four different categories or generations of biofuels. Ethanol, from crops like corn, is considered a first-generation biofuel. Second generation biofuels are made from non-food sources like wood, straw and crop waste. Third generation biofuels are produced by algae that produce oil. Fourth generation biofuels are made from genetically modified algae.
- Do more research and discuss the pros and cons of the different methods of producing biofuels. Consider what resources are required to produce/grow the feedstock. Which biofuel sounds like the most sustainable option? Have participants share their thoughts in a Pros & Cons Organizer.