Cornmeal, Molasses and Yeast Medium
Updated March 14, 2012
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This soft medium should be used fresh. It is the medium that was used at Bloomington for many years. We prefer our current medium because it is less subject to bacterial contamination, it resists liquification, making it a vastly better shipping medium, and it stores well. The cooking instructions are those we used at the time. See our current food recipe for the approach we use now. Nutri-Fly™ Molasses Formulation (Genesee Scientific) is a pre-mixed version of this recipe.
The recipe
Water 2.66 liters
Yeast 33 grams
Yellow cornmeal 163 grams
Agar* 16 grams
Molasses 200 milliliters
10% p-Hydroxy-benzoic acid methyl ester in 95% ethanol 38 milliliters
*adjust agar concentration according to the gel strength of your agar
Cooking instructions
  1. Stir the agar into about 80% of the water.
  2. Bring to a boil, boil until agar in dissolved.
  3. In the meantime, dissolve the yeast in most of the remaining water (or save a bit for rinsing), then stir in the cornmeal (get all the lumps out).
  4. When the agar is dissolved, add the molasses to the agar/water mix, then stir in the yeast/cornmeal/water mix. Use the remaining water to rinse the dregs into the cooking pot.
  5. Return the mixture to a boil, simmer for 5 to 10 minutes.
  6. Turn off heat source.
  7. Allow to cool for 5 minutes or more, then carefully stir in p-hydroxy-benzoic acid methyl ester.
  8. Dispense.
  9. Allow to cool before plugging if time allows.