Detection of irradiated ingredients included in low quantity in non-irradiated food matrix. 2. ESR analysis of mechanically recovered poultry meat and TL analysis of spices.

Protocols EN 1786 and EN 1788 for the detection of irradiated food by electron spin resonance spectroscopy (ESR) and thermoluminescence (TL) were not conceived for the detection of irradiated ingredients included in low concentration in nonirradiated food. An enzymatic hydrolysis method, realized at 55 degrees C, has been developed for the extraction of silicate minerals and bone fragments. When followed by a purification of the extracts by an aqueous solution of sodium polytungstate, this method made it possible to detect very low inclusions of irradiated spices (0.05%, wt/wt by TL) included in various meals (cheeses and precooked meals). Even for food containing together two ingredients (spices and mechanically recovered meat), it was possible to detect and identify them simultaneously.