Saccharomyces cerevisiae

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Saccharomyces cerevisiae
yeast 
Type fungi 
Domain fruit & grain skins 
Gram state dependent 
O2 facultative anarobe 
Carbon Sources
Glucose yes 
Lactose no 
Sucrose yes 
Enzymes
Catalase yes

Uses

Primary

Natural Occurrence

  • This species of yeast does occur naturally

Hazards

  • GRAS and safe for oral consumption as food.

Character

This species:

  • is aerobic and a facultative anaerobe.
  • can use ammonia or urea as the sole nitrogen source, but not nitrates.
  • is a top fermenter, meaning it tends to migrate to the top of fluids in which it feeds by maintaining contact with the bubbles of carbon dioxide it produces
  • experiences optimum growth between 30–35 °C (86–95 °F)
  • produces maximum carbon dioxide at 31°C
  • this species goes dormant at low temperatures (5°C)
  • goes dormant at lower temperatures (5°C)

Cultivation

  1. Grind 1/2L of grain very fine
  2. Mix it into 2L of water
  3. Place the mixture in a well-washed well-rinsed clean bowl with a wide brim
  4. If possible, place a screen or fine-woven mat over the pot in place of a lid. It would let the air flow in freely, but not bugs.
  5. Wait one day
    Check: If the solution is not fizzing (carbonated, small bubbles rising from within) discard it and repeat from the beginning.
  6. Discard any foam on top of the water

See Also