Microorganisms & Food Production Noadswood Science, 2012

Microorganisms & Food Production Saturday, April 15, 2017 To know how microorganisms and used within food production

Useful Microorganisms There are many microorganisms which are useful in the manufacture of food… Beer, wine, cheese, yogurt and bread are all examples of foods and drinks which need microorganisms to be made The main microorganisms involved are bacteria and fungi (specifically yeast)

Making Yogurt & Cheese Bacteria are used to ferment milk into yogurt and cheese – the acid produced by the bacteria thickens the milk in yogurt making In cheese making, rennet (a variety of enzymes) is added to separate the milk into solid curds and liquid whey (the curds are then pressed into solid cheese)

Making Bread Yeast is used in bread making – as it respires it releases carbon dioxide bubbles which spread through the dough making it rise – any alcohol produced evaporates off in cooking…

Making Beer & Wine Yeast is a fungus that can live on the surface of fruit – to obtain its energy it feeds on sugars, producing carbon dioxide and water In a brewery fermenter the growth rate becomes very rapid which means the organism runs out of oxygen because there are so many cells in the reaction vessel As the organisms run out of oxygen there respiration switches from aerobic to anaerobic – alcohol and carbon dioxide are produced: - C6H12O6 → 2C2H5OH + 2CO2 + Energy

Yeast Fermentation Many people find fermentation economically important – ranging from the manufacture of alcoholic drinks, the baking of bread to the work of agricultural and industrial chemists Worldwide in 1998, 31 billion litres of alcohol were produced and 93% was from fermentation – in order to obtain maximum alcohol production it is important that the producer of alcohol provides the optimum conditions

Yeast Fermentation All living organisms need the best conditions possible if they are to grow and reproduce successfully – changes to, or the absence of, the optimum conditions will usually mean that the organism in question is affected in some way Yeast is a micro-organism used in the brewing industry to produce beer and wine. Like any organism, the yeast needs energy to carry out its life processes, grow and reproduce – the yeast releases energy from sugar by respiration

Experiment Carry out the beer experiment – be as precise as possible as you carry out the experiment…