Adenosine Triphosphate (Atp) is a molecule that is a universal energy store. It comprises one xylose sugar, the adenine base, and three phosphates. One of the phosphates is linked through a high-energy bond which, when split, fuels reactions such as biosynthesis, transportation, etc.

ATP is generated in catabolic processes such as glycolysis (“sugar breakdown”). In turn, ATP is consumed in reactions that demand an input of energy, e. g., the biosynthesis of cellular materials in anabolic reactions.

The detection of ATP can be used as a rapid test for the hygiene status of equipment and products. Wherever there is or has been growth of microorganisms in locales that have not been efficiently cleaned (e. g., in the Cleaning in Place [CIP] systems that are widely used in modern breweries to clean vessels and pipes), the soil will contain ATP. This can be detected through ATP bioluminescence. A swab swept across a surface is broken into a reaction mixture that includes a substrate luciferin and an enzyme called luciferase. (This is the enzyme whose action leads to the light generation in firefly tails.) If ATP is present, then the reaction can proceed, with the production of light. The intensity of light production is proportional to the amount of ATP present and, in turn, to the amount of contamination present. ATP testing is considered a powerful tool for quality assurance in modern breweries.