Sugar to Ethanol conversion
- Each molecule of sugar gets converted by the yeast, to two molecules of
ethanol, and two molecules of carbon-dioxide gas.
C6H12O6 = 2x C2H5OH + 2x CO2
1 mole of sugar molecules weighs 180.1g, one mole of ethanol is 46.1g, and
one mole of CO2 is 44.0g
So ... 180g of sugar will make (46.1 x 2 =) 92g of ethanol.
Or, 1kg of sugar will make 511g of ethanol (eg 51.1%)
We don't normally weigh the ethanol, but rather measure its volume.
Ethanol has a density of approx. 0.789 g per mL, so 511g will take up 648 mL
(hmm... this is different to my earlier 430 mL per kilo on the website ...
looks like I'd multiplied when I should have divided.)
E.g. 1kg sugar can only make a maximum of 648 mL of pure (100%) alcohol.
At 80% purity, this would be 810 mL. So 7 kg sugar would yield a maximum of
5.67 L at 80%
This is assuming ALL the sugar is used to make ethanol. Some gets consumed
by the yeast when it breeds and multiplies, some is not fermented fully, and
some of the alcohol is left in the pot and never fully collected.