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YeastBrewing is a natural process which depends on a small, plant-like organism called yeast. Yeast grows and multiplies by feeding on various types of sugars, which it turns to energy. It needs small amounts of oxygen to do this. As well as energy to grow, yeast also produces energy in the form of heat, along with water and a gas called carbon dioxide. In fact we use sugar and oxygen in the same way ourselves, obtaining energy from our food. However, once the oxygen has been used up, yeast does something we certainly can't - it generates alcohol. This is fermentation and the sugars that the yeast can digest are called fermentable sugars.
Take Care Of The YeastYeast is alive when it's used for fermentation. If it's treated badly - kept too hot or too cold for instance - it stops working, as you might do yourself! Neither can it survive being kept too acid or too alkaline; both will quickly damage it. The best conditions are known as the "correct pH".This means that the whole of the brewing process has to be carefully controlled to allow the yeast to do its job; and this is a major part of the brewer's skill.
Yeast Handling And RecoverySkimming and cone removal are two methods by which yeast may be separated from the rough beer, and removed to storage vessels. However, rather than simply waiting until the yeast sinks and clears the beer, we can put the beer through a centrifuge. This is a machine like a spin dryer, which by rotating very fast causes much of the yeast to separate out immediately. This is then drawn off for recovery.![]() [Console] [Yeast] [Malting] [Milling] [Mashing] [Cereal Cooker] [Mash Mixer] [Lauter Tun] [Copper] [Whirlpool] [Wort Cooler] [Fermentation] [Maturation] ![]() [Contents] [1927] [Heritage] [Mystery Tour] [Brewery] [Geordie] [Connoisseur] [Screensaver] [Feedback] |