Non-destructive determination of the fat content in glazed bigeye tuna by portable near infrared spectrophotometer

Abstract

The non-destructive determinations of the fat content in glazed and thawed bigeye tuna using a portable near infrared (NIR) spectrophotometer were performed. For frozen bigeye tuna, a sufficient and accurate calibration equation could not be obtained using the NIR method under glazed conditions. The most accurate section for the NIR measurement of fat content in bigeye tuna was the upper abdomen section near the anus. The accuracy of the calibration equation increased by removing the glaze. In addition, the accuracy became even higher with thawed tuna. For frozen bigeye tuna, the temperature compensation type calibration equation was efficient for the fat determination after removing the glaze.