OCCURRENCE OF POLYCYCLIC AROMATIC-HYDROCARBONS IN CHEESE WITH AND WITHOUT A SMOKED FLAVOR

Two groups of cheese were analysed for their polycyclic aromatic hydro carbon (PAH) content. The first group was composed of 24 highland Swis s L'Etivaz cheeses manufactured using an open fire with logs, and 25 S wiss Gruyere cheeses manufactured in a steam heated vat as a reference . In the highland cheese, anthracene was often present; fluoranthene, fluorene and naphthalene were found occasionally. All these compounds are related to the processing technology. Phenanthrene and pyrene were found in a higher concentration in the highland cheeses than in the r eference cheeses, thus indicating that the latter compounds originated from both the environment and the smoke of the fire. In conclusion, t hese various components may be considered as labelling substances for highland cheese with a Protected Designation of Origin (PDO). The seco nd group was comprised of 18 Swiss or foreign cheeses, 9 with and 9 wi thout smoke flavour as reference. In most cheeses treated with warm sm oke, the same PAH occurred in a much higher concentration than in the highland cheeses previously considered. Moreover, several other PAH we re found such as benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoran thene. Benzo(a)anthracene is present in trace amonts in all cheeses an alysed and seems to be a pollutant that is not related to the smoking procedure. Liquid smokes (9 = 3) do not contain any PAH but are nevert heless highly efficient flavouring preparations. Their use may consequ ently he recommended as a valuable alternative procedure resulting in lower risks to human health in comparison with the use of warm smoke.