Yeast industries

1
Yeast industries

• Lesson 2 Using yeast in beer-making

2
Using yeast to make beer

• Yeast makes alcohol and carbon dioxide from
  sugar.
• Alcohol makes beer alcoholic
• And carbon dioxide makes beer fizzy

Fizzy, alcoholic, beer
3
Beer ingredients

• Beer is made from yeast, water, barley and sugar.
• It is flavoured with hops.

Barley grains
4
Malting barley

• Barley grains are full of starch.
• They are allowed to sprout so that they turn
  their starch to sugar.
• This is called malting.
• Then the yeast goes to work on the sugar, turning
  it to alcohol and carbon dioxide

5
Alcohol in beer

• The alcohol content of the beer depends on
• The type of yeast used - different yeasts stop
  working at different alcohol concentrations.
• Temperature
• The length of time the beer is allowed to ferment.