Origin of disinfection by-products in cheese.

The disinfection of water, equipment and surfaces in a cheese factory is one of the factors that can originate disinfection by-products (DBPs) in cheese. This research has focused on studying cheese factories in order to evaluate the individual contribution of each step of the cheese-making process that can contribute to the presence of DBPs in cheese. Ten factories were selected according to their salting processes (brine or dry salting). Each factory was monitored by the collection of six representative samples (factory water supply, brine solution, milk, whey, curd and cheese) in which the concentrations of up to eight chemicals were detected. The study shows that contact with brine solutions containing significant levels of DBPs is the main source of these chemicals in cheese. A minor factor is the pasteurised milk used in their manufacture.