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Bromelain experiment

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Julia Richards

on 2 March 2014

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Transcript of Bromelain experiment


protein molecules that act as biological catalysts, or substances that increase the rate of a chemical reaction without any permanent change to the substance itself.
The enzymes used in this experiment is
Found in fresh pineapple.
If not kept with the correct environmental factors, can be easily changed or broken down in a process called denaturation.
The Bromelain Testing Lab is designed to show how temperature affects the function of the enzyme.

If the enzyme, bromelain, is used in a temperature other than approximately 37 degrees celsius, then it will become denatured and the gelatin will not be broken down.
What is Bromelain?
There are thousands of enzymes, one of which is the enzyme bromelain.
Bromelain is an enzyme that digests or breaks down proteins.
Juice a pineapple using a knife,
blender, and cheesecloth

Use just the fresh pineapple juice

This is where the bromelain enzymes are acquired from

Number the test tubes from 1-5.

Assign each test tube a temperature

RT- 20ºC
#2- 40ºC
#3- 60ºC
#4- 80ºC
#5- 100ºC

Next, add 3 ml of pineapple juice to each test tube.

Then, heat each test tube to the appropriate temperature as assigned in a glass beaker containing 150ml of water.

After 24 hours
The Effect of Temperature on Enzymes
After removing all of the test tubes from the water, add 10 ml of Knox gelatin (prepared in step 1) to each test tube and mix well.

Place the test tubes in the refrigerator overnight.

The next day, record the solidification and amount of remaining liquid in the each test tube.
Lab Set Up:
Emily Oakes
Julia Richards
Period 7

Pineapple Juice
The room temperature test tube remained completely liquid.
Test tube #2 was also liquid on Day 2.
Test tube #3 was mostly gelled with a little excess liquid on top.
Both test tube #4 and #5 gelled completely.
After measuring the amount of remaining liquid, all of the data was put into a table:

What does this show?
The data shows that bromelain denatures or stops breaking down the gelatin between 60 and 80 degrees Celsius.

Between 60ºC and 80ºC little to no liquid remains

This means the original hypothesis of 27ºC was rejected.
Sources of Error
Many things could have effected the outcome of the experiment, including:

cleanliness of glassware

inaccuracy of measurements

This could have been prevented by paying closer attention to both the cleaning and ingredients.
Why is this useful?
Learn how temperature effects enzymes

Also provided information to help in real life situations for chefs, bakers, or people on how to make pineapple flavored gelatin.
WebMD.Therapeutic Research Facility,2009. Web. 13 February 2014.
World Health. American Academy of Anti-Aging Medicine,30 December 2005.Web.13 February 2014.
Chemistry for Biologists. Royal Society of Chemistry,n.d.Web.14 February 2014.
Ophardt, Charles E.Virtual Chembook.Elmhurst College, 2003. Web. 13 February 2014.
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