Method to detect bone fragments during the processing of meat or fish

A method for detecting bones, bone fragments, and shell fragments on or near the surface of animal flesh during processing comprising:

• a. illuminating the surface of a product comprising animal flesh with UV or visible light having a wavelength effective to elicit fluorescence of animal bones or shells,
• b. measuring the intensity of fluorescent light emissions from said surface at first and second wavelengths, wherein said first and second wavelengths are selected to yield a substantial difference between the ratio or subtractive difference for bones or shells, and the ratio or subtractive difference for animal flesh, wherein said ratio is the ratio of said fluroescent light emission intensities measured at said first and second wavelengths and said subtractive difference is the mathematical difference between said fluorescent light emission intensities measured at said first and second wavelengths,
• c. calculating a comparison value of said fluroescent light emission intensities measured at said first and said second wavelengths, wherein said comparison value comprises the ratio of said fluroescent light emission intensities measured at said first and said second wavelengths or subtractive difference between said fluorescent light emission intensities measured at said first and said second wavelengths, and
• d. determining the presence or absence of bones, bone fragments, or shell fragments from said comparison value.