6 research outputs found
Fast and Green Method to Control Frauds of Geographical Origin in Traded Cuttlefish Using a Portable Infrared Reflective Instrument
An appropriate seafood origin identification is essential for labelling regulation but also economic and ecological issues. Near infrared (NIRS) reflectance spectroscopy was employed to assess the origins of cuttlefish caught from five fishing FAO areas (Adriatic Sea, northeastern and eastern central Atlantic Oceans, and eastern Indian and western central Pacific Oceans). A total of 727 cuttlefishes of the family Sepiidae (Sepia officinalis and Sepiella inermis) were collected with a portable spectrophotometer (902\u20131680 nm) in a wholesale fish plant. NIR spectra were treated with standard normal variate, detrending, smoothing, and second derivative before performing chemometric approaches. The random forest feature selection procedure was executed to select the most significative wavelengths. The geographical origin classification models were constructed on the most informative bands, applying support vector machine (SVM) and K nearest neighbors algorithms (KNN). The SVM showed the best performance of geographical classification through the hold-out validation according to the overall accuracy (0.92), balanced accuracy (from 0.83 to 1.00), sensitivity (from 0.67 to 1.00), and specificity (from 0.88 to 1.00). Thus, being one of the first studies on cuttlefish traceability using NIRS, the results suggest that this represents a rapid, green, and non-destructive method to support on-site, practical inspection to authenticate geographical origin and to contrast fraudulent activities of cuttlefish mislabeled as local
Comparison of Visible and Near-Infrared Reflectance Spectroscopy to Authenticate Fresh and Frozen-thawed Swordfish (Xiphias gladius L)
This study evaluated near-infrared (NIR) and visible-NIR (Vis-NIR) spectroscopy as a way to distinguish fresh (F) from frozen-thawed (T) swordfish cutlets (Xiphias gladius). A total of 90 F and 60 T samples were used. The T samples were stored at a high and low frozen temperature (HT: -10\ub0C; LT: -18\ub0C). Spectra were collected using a Vis-NIR portable spectrophotometer (380\u20131080 nm) and a NIR monochromator (1100\u20132500 nm). The percentage of correctly classified samples obtained with Vis-NIR spectroscopy was 6596.7%, whereas that for NIR was 6590.0%. The best classification was observed comparing F and HT samples using Vis-NIR (100% vs. 96.7%, respectively). The more descriptive principal component scores (PCS) of NIR and Vis-NIR were used with a multivariate binary logistic regression. The model with the PCS of the first two Vis-NIR principal components accounted for 81.1% of the classification. Vis-NIR could be a strategic tool to screen the cold treatment of swordfish
Validation of NIRS analysis in Authentication of Fresh and Frozen-ThawedFish Products
Providing label information about the preserving method used for fish conservation (eg. chilling or freezing) could have a strong influences on consumer acceptance. Thawed fish is more susceptible to microbial invasion than fresh fish, with a consequent reduction of its shelf life1. This should be strongly considered on management plans, such as the HACCP (Hazard Analysis and Critical Control Point) system, to reach higher standards of seafood quality and safety. The substitution of thawed products labeled as fresh is a common commercial fraud. There are numerous techniques available to distinguish fresh-chilled from frozen-thawed fish, having different performances. This study was the first part of a collaborative trial among different laboratories. The ring trial was carried out to evaluate the discriminating ability of three analytical techniques, a histological method, front-face fluorescence spectroscopy and infrared spectroscopy (IRs). This paper only reports the performances of IRs techniques, in terms of their specificity, sensitivity, accuracy, intra-laboratory reproducibility and agreement with the Standard test for authentication of fresh and thawed Gilthead Sea bream (Sparus aurata) fillets
NON-DESTRUCTIVE NON TOUCH VISIBLE-NIR TRANSMITTANCE SPECTROSCOPY FOR IDENTIFICATION OF FRESH AND FROZEN-THAWED FISH
The online evaluation of the quality and freshness of the seafood is usually done through the employment of trained
operators. This practice is costly in economic terms and requires a period of training of technicians. For certain frauds
(eg. defrosted as fresh) also are not yet available objective assessment criteria, particularly for products already
processed, sliced or filleted. The handling of the product reduces the shelf-life by making the fish susceptible to
microbial growth. This study was carried out to evaluate the discrimination power of a portable Visible-NIR
transmittance spectroscopy on fresh and thawed fish products