AbstractThe hazard analysis critical control point) (HACCP) system is set up with the aim of ensuring the harmlessness of food along the process chain, from the producer to the ultimate consumer. To set up this system, it is necessary to perform an analysis to identify the dangers and the critical points of the process in real time. Living organisms are detected on the principle of measurement of cellular energy in the form of adenosine triphosphate (ATP), which is produced by all living cells and of particularly by microorganisms. The principle of the bioluminescence of firefly luciferase is applied, whereby a reduced form of luciferin, together with a molecule of oxygen and ATP in the presence of the enzyme luciferase, produces a reaction in which oxyluciferine is released, together with AMP. This is accompanied by a simultaneous release of photons, which are then quantified. The emission spectra recorded with the firefly luciferin/luciferase system is obtained with absolute sensitivity. The method of ATP assays here proposed is adapted for measuring the total content of different adenylates in the cell, i.e. the adenylate pool. ATP concentration is then measured through bioluminescence, i.e. the light is measured by a photomultiplier tube detector and the signal is converted to relative light units (RLU). Thus, RLU have a relationship with the amount of ATP present in the sample, which is not the case with traditional methods. Adequate levels of sensitivity are calculated with appropriate controls and the readings are translated into a statistical designation of positive or negative result. There are numerous illustrations of HACCP applications using biochemiluminescence (BCL) techniques as detection technology in food industry production lines and in control of critical points in real time in industrial applications. Copyright © 2001 John Wiley & Sons, Ltd.