Difference between revisions of "Fermentation"

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Fermentation is process by which [[yeast]] converts various simple sugars into ethyl alcohol and carbon dioxide gas.  It can take many forms, and only certain types of fermentations produce end results which are pleasant to drink.
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Fermentation is process by which [[yeast]] converts various simple sugars into ethyl alcohol and carbon dioxide gas.  It can take many forms, and only certain types of fermentations produce end results which are pleasant to drink. Chemically, the conversion by which yeast turns sugar into alcohol is:
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Sugar → Alcohol + Carbon Dioxide + Energy
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or, in chemical notation:
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C<sub>6</sub>H<sub>12</sub>O<sub>6</sub> &#8594; 2C<sub>2</sub>H<sub>5</sub>OH + 2CO<sub>2</sub> + energy
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Yeast is also capable of producing energy aerobically (with oxygen extracted from the air) by the conversion: Sugar + Oxygen &#8594; Carbon Dioxide + Water + Energy
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or:
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C<sub>6</sub>H<sub>12</sub>O<sub>6</sub> + 6O<sub>2</sub> &#8594; 6CO<sub>2</sub> + 6H<sub>2</sub>O + energy
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The second conversion produces far more energy, largely because the entire sugar molecule is broken down and converted, but is only possible in the presence of sufficient oxygen; the first conversion on the other hand can be carried out with only sugar present. For this reason, fermentation for the production of alcohol should take place in a low oxygen environment to ensure that sugar is converted to alcohol instead of carbon dioxide and water.
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=Primary Fermentation=
 
=Primary Fermentation=

Revision as of 20:16, 17 February 2007

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Fermentation is process by which yeast converts various simple sugars into ethyl alcohol and carbon dioxide gas. It can take many forms, and only certain types of fermentations produce end results which are pleasant to drink. Chemically, the conversion by which yeast turns sugar into alcohol is:

Sugar → Alcohol + Carbon Dioxide + Energy

or, in chemical notation:

C6H12O6 → 2C2H5OH + 2CO2 + energy

Yeast is also capable of producing energy aerobically (with oxygen extracted from the air) by the conversion: Sugar + Oxygen → Carbon Dioxide + Water + Energy

or:

C6H12O6 + 6O2 → 6CO2 + 6H2O + energy

The second conversion produces far more energy, largely because the entire sugar molecule is broken down and converted, but is only possible in the presence of sufficient oxygen; the first conversion on the other hand can be carried out with only sugar present. For this reason, fermentation for the production of alcohol should take place in a low oxygen environment to ensure that sugar is converted to alcohol instead of carbon dioxide and water.


Primary Fermentation

Secondary Fermentation

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