The term fermentation is applied to the anaerobic degradation of carbohydrates.Ultimately the purpose of fermentation is to make energy available to a living cell,since carbohydrate molecules are quite rich in stored energy. Whether or not a particular carbohydrate is fermented depends upon the enzymes produced by the organism. During fermentation,most bacteria produce different types of acids & gases. The end product of fermentation varies from one organism to also upon the enzymes present in them. Some of these ends can be detected in lab. Thus, the ability of organisms to break a single sugar, combination of sugars or various other carbohydrates in media provides information for the classification of a bacterial spp.
Acid production can be determined by the used of indicators of pH media containing carbohydrates.A commonly used pH indicator is phenol red, which is red at pH 8.5 & yellow at pH 6.9. In addition,gas production can be determined by the use of small inverted tubes called Durham's tube which collects any gas that might be given off as end product of fermentation.
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Cited By Kamal Singh Khadka
Assistant Professor In PU, RE-COST, PNC, LA, NA