Baking, Brewing and Making Yoghurt

• Yeast and sugar is put into the flour
• The yeast uses the sugar and respires aerobically (with oxygen) to create carbon dioxide and water
• This makes the bread expand and rise due to the air (CO2) spaces being created in the bread
• Process is speeded up by warmer temperatures- hence placing bread in the oven.
  

• MALTING- the starch in Barley is broken down into a sugary solution by enzymes
• Fermention (anaerobic respiration) occurs when the yeast is added, producing ethanol (alcohol) fromt he sugary solution
  
• During wine making the fruit is used as an energy source by the yeast
  
• BEER- hops are added for taste
  

• LACTOSE= the sugar in milk
• Milk is boiled, then brought down to about 40 degrees c
• A bacteria culture is added and they ferment (respire anaerobically) to produce lactic acid
• This makes the milk clot, forming yoghurt

IN CHEESE MAKING...

• The solid "curds" in the milk are packed together and left to mature to make cheese