is an analytical technique used to detect microbial contamination in the brewing process by measuring the presence of adenosine triphosphate (ATP) in samples taken in the brewery. See adenosine triphosphate (atp). The detection and measurement of ATP indicates the presence of living cells because ATP is broken down when cells die. The analytical method involves the use of the luciferin–luciferase enzyme system, which fireflies use to emit light. In the presence of oxygen and ATP, the enzyme luciferase produces light that can be measured. The quantity of light emitted is related to the amount of ATP present and therefore to the quantity of living cells present at the time of sampling. Up to 1,000 microbes per sample can be detected in a few minutes, although the method is unable to discriminate between specific types of microorganism. The technique is used in breweries to monitor the cleanliness of the brewing plant and equipment and is preferred to traditional microbiological analysis because of its speed and its relative simplicity. It can be used routinely by plant operators to assess the effectiveness of cleaning regimes. More traditional microbiological sampling routines can take several days to obtain a result. The technique is used predominantly in larger breweries because of the high cost of the system. However, because the method does not require the skills of a trained microbiologist to monitor microbiological contamination, it is likely to eventually find application in smaller breweries.
