5.5 Beer production

• Beer
• An alcoholic substance
• Obtained through fermenting yeast in water
• Sugar from plant material is mixed in water
• Barley
• Converts sugar into ethanol and CO2 
• Yeast is a natural catalyst
• Sugar -> ethanol +CO2
• C6H1206 -enzyme in yeast-> 2CH5OH+2CO2
• The barley's starch is broken down into sugar
• Easier for the yeast to ferment it to ethanol
• When the barley seed germinates (Malting), it produces amylase (an enzyme)
• Breaks down starch into maltose
• Used by the yeast as an energy source
• Sugar from the barley is obtained through boiling it
• Hops are then added to adjust the flavor
• Also stops bacteria from growing
• Yeast is then added
• Uses up all oxygen and starts to respire