An apparatus 1 for bone or foreign object detection in poultry comprises laser height measurement means 8, 9, for creating a pseudo x-ray image of a food item 3 e.g. chicken, to be scanned, x-ray imaging means 6, 7, for creating an x-ray image of said item and means for comparing the pseudo x-ray image and the x-ray image, so as to improve foreign object detection in said item 3. The pseudo x-ray image may be subtracted from the x-ray image to determine whether there is a difference, which may show up as an occlusion in the image, indicating the presence of bones. There may be high-energy 4 and low-energy 6 x-ray generators which may be combined to allow dual-energy x-ray detection. Zoning may be used to identify regions where occlusions in the subtracted image indicative of bones or foreign objects are more likely, such as edge regions of the meat item 3. A method of optimizing detector performance in a dual-energy x-ray detector system is also disclosed, where different scanning rates, integration times or
