Difficulty of Project
Approximately $10 for food supplies, and $10 for a candy thermometer if one isn’t owned previous. All other materials needed are already in your kitchen.
Care should be taken when dealing with heating water and using knives.
Most equipment is available in a standard kitchen. Consumable supplies can be purchased at any grocery store.
Approximate Time Required to Complete the Project
The entire experimental portion of the project can be with 1 hour of prep time and 1 hour of data collection!
The project tests the effect of heat- at varying temperatures- on the viability of biological enzymes. Put simply, at what temperature do enzymes stop working?
To pinpoint at exactly what temperature the enzymes in fresh pineapple no longer work.
Materials and Equipment / Ingredients
- Fresh (not canned!) pineapple, cut into cubes no larger than 1”x1”
- Jello, prepared ahead of time and cut into flat slabs, 2” x 2” x 1/2”
- Candy or meat thermometer
- Pot to heat water/pineapple chunks
- 5-10 dishes to put pineapple cubes after heating
- Tray to conduct the experiment on ( any baking tray will do)
All materials can be found either in your kitchen or at the grocery store!
Enzymes are the ‘worker’ molecules of life. Every single chemical reaction in your body is regulated by a specific enzyme.
Enzymes need specific conditions to work properly, and can be destroyed if those conditions change. Temperature is one of those conditions.
An enzyme in pineapple has an amazing ability to break down the chemical bonds that make Jello solid- if fresh pineapple is placed on Jello, it will liquefy it. When you find pineapple chunks in solid Jello salad they don’t do this, however- that’s because the pineapple was added when the Jello was still hot, killing the enzymes. The question is, how hot does it need to be before the pineapple enzymes stop working?
- What is an enzyme?
- What can destroy enzymes?
- What do enzymes do?
- How do enzymes work?
- What is homeostasis?
- What conditions are needed for enzymes to work?
- How are enzymes created in a cell?
Terms, Concepts and Questions to Start Background Research
Enzyme, Homeostasis, Temperature, Increment, Celsius, Fahrenheit,Degree,
For middle school:
Basic data tables, the concept of temperature in C and F, the role of enzymes in living organisms, the basics of homeostasis ( “same state” in latin)
A more advanced conception of homeostasis ( mostly temperature and pH), formation and folding of enzymes, what it means to “denature” an enzyme.
- Prepare one package of your favorite flavor of Jello
- Cut the Jello into rectangular slabs,
- Cut fresh pineapple into 1” cubes ( note: the pineapple must be fresh- canned pineapple has been pasteurized, and any active enzymes were killed by the processing)
- Fill a pot with cold tap water. Take the initial temperature and record it.
- Put at least 10 cubes of pineapple in the pot.
- Put the pot on low heat. With an eye on the thermometer, remove cubes of pineapple at 5° increments. Place the pineapple in separate bowls to avoid cross-contamination.
- Place the cubed of pineapple on the slabs of jello, and note whether the jello is liquefying beneath the pineapple. Record your data.
- Enjoy Dessert!