Three is good enough for me; Ona (2), Ila (1m.) and Dax (5).

Blessed with an abundance of little germ factories in my house, I had options when trying out this recipe for taking a bacterial culture from kids. Ona was quick to volunteer  her hands for the experiment, and Dax took notes. Below are the instructions we followed in preparing our agar plates. The results looked like yeast and maybe some kind of slime mold??? We also failed to completely dissolve the beef bouillon cube, so we most certainly skewed our results toward sugar-loving microbes. Try it and share your findings with me, eh?


Preparing a Bacterial Culture from one of your ‘Germ Factories’:

  1. Collect a sterilized glass jar with tight fitting lid, 2 pouches of flavorless gelatin, 1 low-salt beef bouillon cube, 2 tsp. sugar, and a few sterile cotton swabs along with your germ factories.
  2. Prepare your own petri dish by mixing one c. boiling water with the gelatin, bouillon cube and sugar, mixing until dissolved. Carefully pour this mixture into the sterile jar. Once the mixture is room temperature, attach the lid tightly. Turn the jar onto its side and allow the gelatin to cure. This is the agar or food your bacterial culture will grow on.


  1. Using a sterile swab, collect your bacteria sample by swabbing the surfaces of your object which you believe to have had the most human or surface contact while in use. Now gently rub this swab in a zigzag pattern across the surface of the cured gelatin mixture in your jar.
  2. Seal the jar and label it with the date and where the culture was taken from. Place in a dark, room temperature place. In 3-7 days, you will see bacterial colonies growing on the surface of the agar, all with different colors, textures and patterns.
  3. Visually identify the kinds of bacteria you’ve grown by visiting the gallery page of a site like What do these organisms tell you about your personal, familial or public life? Submit a picture of your experiment to to be included in our online project log & receive updates on other’s contributions.
  4. Be sure to dispose of your cultures carefully, disinfecting all contact surfaces when finished. Pass the ‘Cultural Object’ along to someone else and encourage them to try it, comparing notes.

Note; I found that the bouillon really needed a good stir to dissolve well! 


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