DESCRIPTIVE STUDY OF REFLECTANCE SPECTRA OF HAKE (MERLUCCIUS AUSTRALIS), SALMON (SALMO SALAR) AND LIGHT AND DARK MUSCLE FROM TUNA (THUNNUS THYNNUS)

Abstract

The reflectance spectra of foods constitutes a simple, non‐destructive physical method with potential applications in the industry. Color is the most valued properties for customers when buying fresh fish, so that its characterization is important for setting objective quality criteria that can be easily applied at all levels of the production and distribution chain. In this work the reflectance spectra and CIEL*a*b* coordinates of fresh muscle in hake, salmon and tuna (light and dark muscle) it was described. Hake, salmon and the dark tuna muscle show a zone of the spectrum (between 600 and 740 nm) with no significant (P > 0.05) differences between the reflectance percentages, which may be taken as characteristic of fresh fish muscle. The light tuna muscle shows a plateau between 700 and 740 nm, while the dark muscle presents a further two plateaus between 390 and 440 nm and between 470 and 510 nm. PRACTICAL APPLICATIONS The study of the reflectance spectra of fish is a method with many potential applications in the food industry. Spectrum shape is characteristic of each fish. For this reason, a study of the reflectance spectra of the “fresh meat” of commercially interesting fish species could be of value as tool for characterizing fish and fish products. In each case it will be necessary to identify the characteristic wavelengths or spectral regions that provide the “digital footprint” of the species in question. Its characterization is important for setting objective quality criteria that can be easily applied at all levels of the production and distribution chain.

Combined effect of probiotics on prolonging the shelf life of GIFT tilapia fillets

“…Colour is considered significant properties for acceptance of fish products due to direct effect on consumer's selection (Lawless & Heymann, 2010). No any significant difference and effect on colour were reported (Özyurt et al., 2015; Sathivel, 2005) except low values of redness in hake fillet (Lopez de Lacey et al., 2014; Sánchez‐Zapata, Pérez‐Alvarez, Fernández‐López, & Barber‐Valles, 2010) which resembles our study and indicated that the colour was stable throughout the storage period in the treatments in which probiotics were used. The fish composition may influence the sensory characteristics like colour, odour and texture during storage (Abdollahi, Rezaei, & Farzi, 2014).…”

Effects of tuna pâté thickness and background on CIEL∗a∗b∗ color parameters and reflectance spectra

“…3 shows the reflectance spectra of samples measured with the white ceramic as background and also the white ceramic reflectance spectra without sample. In some zones, the reflectance spectra of tuna pâté is similar to that of fresh tuna dark muscle (Sánchez-Zapata et al, 2010), although with higher values. Tuna pâté also showed two plateaus characteristic of fresh tuna dark muscle between 360 and 440 nm and 470e550 nm, indicating that this is the same fish species and the same type of muscle (Sánchez-Zapata & Pérez-Alvarez, 2007;Sánchez-Zapata et al, 2010).…”

“…This could be due at the high red component in tuna dark muscle (Sánchez-Zapata & Pérez-Alvarez, 2007;Sánchez-Zapata et al, 2010). Tuna is a fat fish that feeds on zooplankton, which is rich in astaxantin, a carotenoid that accumulates in the muscle of tuna, particularly in dark muscle (Ingemansson, Pettersson, & Kaufmann, 1993), while the Mb concentration in fresh tuna meat is 3e14 times higher than in animal carcasses (Kanoh et al, 1986).…”

“…In fish and fish products, objective color can be studied using CIEL*a*b*, reflectance or near infrared spectroscopy (NIR) (Sánchez-Zapata, Pérez-Alvarez, Fernández-López, & Barber-Valles, 2010). Thus, instrumental color measurements using a spectrophotometer or colorimeter are the most used methods because of their close relationship with the visual perception of the human eye.…”

“…Furthermore, such measurements are made on the surface of the product (as observed by the consumer), are non-destructive, accurate and fast, allowing a better interpretation of color differences (Fuentes-Zaragoza et al, 2009). Reflectance spectrophotometry is a powerful tool for measuring the color of foods, because it measures the color on the surface of the food as observed by the consumer and it is non-destructive (Sánchez-Zapata et al, 2010).…”