How to Cross Breed Yeast

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  1. Image titled Cross Breed Yeast Step 1
    Buy 1 packet of dry baker's yeast and 1 packet of dry brewer's yeast normally found at a local grocery store.
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    Dump the yeast in both packets into a small glass jar. Mix the yeast kinds together.
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    Now to bring the dry yeast to life. Take a cup of distilled water and 2 teaspoons of sugar or splenda, sugar works best, and mix them together. Now pour the sugar water into the jar holding the yeast. The yeast should turn into a brown or yellow blob.
  4. Image titled Cross Breed Yeast Step 4
    Add sugar water daily. You should see the blob start to grow. Take the newly grown slime and put it in a separate jar. Does it change, grow, look, or act different than your first blob of yeast? If so you have created a hybrid colony of yeast. Sometimes you need a microscope to see the differences.
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    If you want to know how this works then read on. Baker's yeast is a species of yeast that reproduces sexually like animals and some plants. It is used to make bread rise. Brewer's yeast is a modified, more complex strain of baker's yeast. It is used to brew beer and wine. They reproduce by merging together than breaking apart into many yeast cells. The 2 different strains merged and split into many hybrid cells.
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  • Yeast grows and reproduces better in the dark.
  • Baker's yeast does not do well in lots of alcohol. Making a small hole in the bottom of the jar helps drain the jar of alcohol. When you feed the yeast hold the jar over the trash.


  • If you eat yeast while raw and slimy it may cause yeast infection.
  • Yeast produces alcohol while feeding, so stay away if you're a teetotaller.

Things You'll Need

  • 2 glass jars
  • Sugar or starch
  • 1 packet dry baker's yeast
  • 1 packet dry brewer's yeast
  • Microscope (optional)

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Categories: Education and Communications