Abstract: Biological control, traditionally considered for field pests, has been recently considered to control stored products pests, and its efficacy has been demonstrated. The presence in processed food of fragments derived from biological control agents could be considered a problem. In this research the results of light filth analysis on semolina and pasta, processed in a plant where Xylocoris flavipes Reuter (Hemiptera: Anthocoridae) and Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae) were released to control stored product beetles, are reported. The aim was to verify if biological control agents can affect the number of fragments in processed food. Light filth analyses were carried out on semolina and pasta samples collected before and during the release of predators and parasitoids in semolina processing plant. The number of fragments detected in the samples collected during the release of the natural enemies was similar to the ones present in the samples collected before biological control. Moreover only fragments of stored products pests were detected, fragments directly related to X. flavipes and A. calandrae lacked.