Quality of Cuttlefish as Affected by Different Thawing Methods

To investigate the effect of different thawing methods on the quality of frozen cuttlefish, six different thawing methods were used: hydrostatic thawing (HT), flowing water thawing (FWT), saline solution thawing (SWT), ultrasonic water thawing (UWT), microwave thawing (MT), and 4°C refrigerator thawing (RT). In this study, the water retention (thawing loss rate, centrifugal loss rate, and cooking loss), pH value, malondialdehyde content, TVB-N value, and sulfhydryl content were measured to evaluate the quality after thawing. Protein secondary structure was measured using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, protein tertiary structure was obtained by fluorescence spectroscopy and water migration was determined using low-field NMR spectroscopy. The results showed that the microwave thawing time was the shortest, but the water holding capacity after thawing was the worst, and the TVB-N content was the highest at 14.31 mg/100 g. Ultrasonic thawing led to the best water holding capacity, but ultrasound promoted the oxidation of protein and fat. Microscopic observation showed that the muscle fiber bundles in the saline solution thawing samples were compactly arranged and intact, with minimal gaps. The samples thawed in saline solution had the highest hardness and chewiness. The results of comprehensive analysis showed that saline solution thawing and ultrasonic water thawing are more suitable for thawing cuttlefish, and this study provides some theoretical basis for the selection of thawing methods in the actual production of cuttlefish.