Abstract: According to the present invention, there is disclosed a system and a method for detecting the presence of fecal contamination or ingesta on objects, such as a protein source, a worker's hands or utensils. In one embodiment, there is included a supporting structure which supports a diffuse light source, the light source emitting light having a wavelength effective to elicit fluorescence from the ingesta or fecal matter at a wavelength between about 660 to 680 nm into an area adjacent to the system, and a light detection device to detect light at a wavelength between about 660 to 680 nm from the area adjacent to the system. The detection of light at a wavelength between about 660 to 680 nm indicates the presence of fecal contamination or other ingesta. There is also disclosed a method of using such a device to detect the presence of such contamination, optionally including further steps to identify the source of any contamination and to modify any practices so that the spread of contamination may be reduced.