[Analysis of volatile nitrosamines in food of animal origin]

A method is described for the fluorescence-spectrophotometric densitometric determination of nitrosamines. For this purpose, foods of animal origin are vacuum-distilled, the distilled-over nitrosamines are extracted with methylene chloride from an acid medium and, after cleavage by hydrogen bromide, the corresponding amines are reacted with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole. The purificaton of the extract and the resolution of the corresponding fluorescent amine derivatives are effected simultaneously by two-dimensional thin-layer chromatography. The determination is achieved by in situ fluorescence spectrophotometry against test substances on the same slab. This method seems useful for investigations into the formation of nitrosamines in foods of animal origin because it permits to detect nitrosamine concentrations as low as 0.1 microgram/kg of food.