Fluorescence of Fish Bones

Abstract

A fluorescence method is described for the qualification and quantification of bones and bone fragments in fish fillets. Bones from six different fish species were shown to exhibit a strong ultraviolet-blue fluorescence (390 nm), when excited by light at 340 nm. The method greatly simplifies searching for bones in fish fillets when they are not deeply embedded in tissue. It is concluded that the method offers promise in the establishment of a routine analysis for inspection of individual fillets in a normal filleting line for bones and parasitic nematodes.

Multivariate Autofluorescence of Intact Food Systems

“…Already in 1985 fluorescence measurements were proposed as a method for detecting bones in fish fillets .…”

Fluorescence of Muscle and Connective Tissue from Cod and Salmon

“…Hasegawa et al (17) used solid sample fluorescence spectrometry on a dried fish model system and found a correlation to the oxidative deterioration. Another application of fluorescence spectroscopy was the development of a method that can detect bones in fish fillets (18). Other sources contributing to the autofluorescence of fish muscle may be proteins, amino acids, NADH, FAD, pigments, and some nucleic acids.…”

Robotics in Meat, Fish and Poultry Processing

“…A detailed spectroradiographic study of the optical characteristics of fish flesh and worms was done by Petursson (1991). Many researchers have tried to find a suitable sensing method for detecting internal worms without success; this includes laser scanning (Hawley, 1988), video candling (Hawley, 1988), fluorescence (Huss et al, 1984) andultrasound (Hafsteinsson andRizvi, 1987).…”

“…Special detection processes have been implemented using either self-fluorescence (Huss et al, 1984) of bone residues or soft X-ray detection (Pulsar, 1990). Both techniques have limitations.…”

“…Using a video camera with a blue or ultraviolet light source, worms on the surface can be detected, and at the same time places where the worms are likely to be found deep inside the fish can be localized and then ultrasound used only in those places. Huss et al (1984) describes the autofluorescence effect of fish bones when using an ultraviolet light source at 390 nm wavelength. These measurements can be implemented quickly (less than 1 s/fish) on commer-46 ROBOTICS in MEAT, FISH AND POULTRY PROCESSING cially available equipment (Lumitech, 1988), but using light at this wavelength, Petursson has shown that it is not possible to see inside the fish, and only bones less than 3 mm from the surface can be detected.…”