Detection of Nematodes in Cod (Gadus morhua) Fillets by Imaging Spectroscopy

Abstract

A promising method for detection of parasites in whitefish fillets has been developed. By use of imaging spectroscopy it is possible to record both spectral and spatial information from an object. In this work it is shown that by applying a white light transmission setup and imaging spectroscopy to cod (Gadus morhua) fillets, it is possible to make spectral images containing information to differentiate between fish muscle and parasites. The spectral images are analyzed by discriminant partial least square regression as well as image-filtering techniques. The method identifies parasites on the surface of the fillets as well as embedded parasites. One parasite was detected at 0.8 cm below the fillet surface, which is 2 to 3 mm deeper than what can be found by manual inspection of fish fillets. The method is nonintrusive and should thus be feasible for industrial purposes.

Ridge detection with application to automatic fish fillet inspection

“…Hyperspectral imaging has been tested as a method for automatic inspection of various food products such as pork (Qiao et al, 2007), poultry (Park et al, 2006) and apples (Mehl et al, 2004). The method has also proven to be an effective method for automatic detection of parasites and blood spots on the surface and embedded in whitefish muscle (Heia et al, 2007;Wold et al 2001). Hyperspectral sensors collects huge amount of data and implementing the method for online applications such as fish fillet inspection is a challenging task.…”

Bruising patterns in commercially harvested yellowtail flounder (Limanda ferruginea)

“…Grunwald and Richards, 2006;Lefèvre et al, 2008;Johnsen et al, 2011;Rotabakk et al, 2011;Olsen et al, 2013). Spectroscopy and/or image analysis software has been used to characterize discolouration (and other defects, such as gaping and nematodes) in herring Clupea harengus (Roth et al, 2007), Atlantic cod Gadus morhua (Heia et al, 2007;Sivertsen et al, 2011;Olsen et al, 2014) and various salmon species (Zydlewski et al, 2008;Erikson et al, 2010;Balaban et al, 2011). The benefits of image analysis include objectivity, as well as the ability to create a reliable baseline from which to compare later research to detect the impact of changes to processing techniques.…”

Spectral Imaging as a Tool in Food Research and Quality Monitoring of Food Production

“…However, the aquaculture and fish processing industries are definitely areas where the added information in a spectral image can be exploited to improve the general quality and/or reduce the production cost e.g. assessment of fat and water content distribution in fillets (ElMasry & Wold, 2008), determination of freshness (Chau et al, 2009), detection of nematodes in cod fillets (Wold et al, 2001;Heia et al, 2007) and detection of melanin spots in Atlantic Salmon fillets (Mathiassen et al, 2007). The consumers associate increased intensity of red in salmonid fishes with superior quality, the fish being fresher and having a better flavour (Gormley, 1992;Anderson, 2000).…”