In the microbiology laboratory different types of media are used to grow microorganisms. Nutrient agar is typically used in the laboratory, but can be expensive to buy and difficult to make in a home setting. Gelatin plates are able to grow various types of fungi as well as some bacteria. Only microorganisms that utilize the enzyme gelatinase will be able to break down the gelatin as a source of protein. If you choose to grow organisms on the gelatin that can use it as a nutrient source, the gelatin will assume a more liquid consistency after the organisms break it down.

The process of creating gelatin plates is simple and can be completed using materials available at the grocery store. This project is intended for people who have had some experience dealing with microorganisms. Growing microorganisms in your home isnot recommended, it is much safer to grow them in a controlled laboratory.


· 1.5 packets of plain gelatin
· 1 cup of water
· 2 teaspoons of sugar
· 4 beef cubes
· 6 Foil muffin cups (these will act as petri plates)
· 6 sandwich bags


· Small pot
· Measuring cup and measuring spoons

Time & Cost

This project should take 30 minutes or less, including the time allotted for the mixture to cool in the foil cups. The total cost for the ingredients required was $8.17 and the recipe makes about 6 nutrient gelatin plates.

Potential Hazards

THE STOVE TOP AND PAN WILL BE HOT. Boiling water will be required in this project, so keep an eye on the pan to make sure the water does not boil over and scald your skin. When pouring the mixture into the foil cups, make sure you do not get it on your skin. Children should only complete this project in the presence of an adult.

Step 1: Gather and Mix the Ingredients

In the pot, mix:
· 4 beef cubes
· 1.5 envelopes of plain gelatin
· 1 cup of cold water
· 2 teaspoons of sugar
<p>Just a thought but maybe you could show a picture of what you grew. Gelatin works well but is consumed. Its is a good alternative to agar if you can't find it. However amazon.ca and many science companies will sell agar.</p>
<p>I made it for a school science fair! Thanks luke, it helped alot!</p>
<p>is sugar necessary to add even if the gelatin is flavored?</p>
<p>do we put the mixture back in the refrigerator after we put it in separate bags? </p>
Yes i did, thank you.
OK, I notice you have corrected the title.
What you have described are actually nutrient gelatin plates, not nutrient agar. The difference is that a great number of bacteria and fungi are able to produce the enzyme gelatinase which breaks down the gelatin ( a protein ) and liquefies the medium. This is unsatisfactory for the isolation of colonies, since they are no longer confined to a solid substrate but mixed throughout the liquid. Agar is a complex polysaccharide derived from seaweed, and the reason that agar is preferred for preparing solid media is that it is resistant to degradation by most microorganisms. Pectin ( another polysaccharide found in fruits ) is a better substitute than gelatin, although many fungi are able to digest it.

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