he wort is sterilised.3.Bittering of the wort occurs via isomerisation of hop alpha-acids.4.Unstable colloidal protein coagulates and precipitates.5.Unwanted flavour components evaporate from the wort.6.The wort is concentrated.The wort is normally boiled vigorously for about I.5 hours with a minimum boiling intensity of 5-8% evaporation per hour.Wort Clarification and CoolingThe degree of wort clarity required depends on the type of beer being produced and on brewing practices. The wort should be clear and free of particles “hot trub” ) before entering the fermenting vessel.Particles, especially small ones, carry lipids which in high concentration have a marked influence on the formation of ester and higher alcohols, as well as the production of other flavour components from yeast during fermentation.The equipment most commonly used for wort clarification is the whirlpool, in which the wort and trub particles are introduced in a tangential mode. Secondary forces on the particles cause them to migrate and accumulate in a cone at the centre of the bottom of the vessel.After clarification, the wort is cooled to a temperature of typically about 10OC. Cooling normally takes place in a heat exchanger. The hot water produced is collected and used as brewing water.Fermentation/Beer Processing AreaFermentationAfter the wort has been cooled to the fermentation temperature, oxygen is added. The wort is then pumped to the fermentation tanks, where yeast is added. Oxygen is necessary to support development of the yeast to a state and amount capable of fermenting wort efficiently. Fermentation is an anaerobic process: the yeast metabolises the fermentable sugars in the wort, forming alcohol and carbon dioxide.Heat is generated during fermentation. To maintain the desired fermentation temperature, the fermentation vessels must he cooled.Once primary fermentation has occurred, the yeast is cropped and pumped to storage tanks. During fermen...
