Question: how long does it take to make homemade yeast?
Answer: Place three to four tablespoons of raisins in your jar. ... 
Fill the jar ¾ full with water. ... 
Place jar at constant room temperature. ... 
Stir at least once a day for three to four days.
When bubbles form on the top and you smell a wine-like fermentation you have yeast. ... 
Place your new yeast in the refrigerator.