Fermentation process

Yeast is used in a batch process to make alcohol in beer and wine.
An enzyme in yeast acts on the natural sugar
in malt (to make beer) and grapes (to make wine).
When the alcohol concentration reaches about 10%,
the alcohol damages the yeast and fermentation stops.
In a batch process the reaction vessel must be emptied and cleaned
and then refilled with the new starting materials. A batch process
takes more time and is more expensive than a .

Different alcoholic drinks contain different amounts of alcohol.
Some people drink alcohol for enjoyment, some drink to excess
and some people become addicted to alcohol.
The harmful effects (physical and social) of drinking excess alcohol
are widespread and reach all parts of society.

Ethanol can be made on a large scale for use as a  or
by the  or the fermentation of sugar cane.
Sugar cane is a renewable resource.
Renewable means that the resource can be replaced.
For example more sugar cane can be grown.
Compare this with the use of  (the )
which are a  resource.