Hobbies And Interests
Yeast as a Living Organism
You can test whether yeast is a living organism by determining whether it has the two key characteristics of all living things: the ability to grow and the ability to use energy (or metabolism). For the energy test, determine whether yeast can metabolize sugar and produce gas. Use two groups of yeast, one with sugar and one without and record the outcomes. To test whether yeast grows, place grains of yeast on a petri dish and add drops of water. Wait for about 24 hours and inspect the grains of yeast beneath the microscope. Record any changes.
Yeast and Fruit Juice
Determine the amounts of fermentation in different kinds of fruit juices after adding yeast. Use the follow aspects of the project as constants: the temperature, the amount of juice, the amount of yeast, the size of the container, the time of fermentation and method of measurement. The only changing variable should be the type of fruit juice. Suggestions for what fruit juices to use include orange juice, apple juice, pineapple juice or grape juice.
Ultraviolet Light on Yeast
Test the effects of ultraviolet light on yeast and yeast fermentation. Put the following items in the control group: the amount and kind of yeast, the UV lamp and its distance from the yeast-filled flask, quantity and type of juice, and temperature and time of fermentation. Mix the juice with yeast in the flask and expose it to UV light over a predetermined period of time. In another group, mix the yeast with water. Record your findings.
Fermentation Project
With this experiment, try growing yeast in different conditions and record the results. Determine whether fermentation will speed up or slow down in different conditions, such as extreme heat or cold. Also use different materials with the yeast, such as vinegar, salt or baking soda. Use balloons to trap the carbon dioxide gas emitted from fermentation, then measure the gas in the balloon. Whichever conditions causes the most fermentation will emit more gas.