Effect of Controlled Freezing‐Point Vacuum Drying on Color and Flavor of Muraenesox cinereus Fillets

Abstract

In this study, the method of maintaining the controlled freezing point and the effect of controlled freezing‐point vacuum drying (CFVD) on the quality of Muraenesox cinereus fillets were investigated. The quality assessment was based on color, 5‐inosine monophosphate (IMP), free amino acids (FAAs) and volatile compounds. Furthermore, comparisons were made among CFVD samples, those dried by hot air drying (HAD) and vacuum freeze drying (VFD). The results showed that the fillet temperature can be controlled within the scope of controlled freezing point by setting the vacuum pressure at 10–12 mbar, turning on the cold trap 40 min after CFVD (at −1 ± 1C) and regulating the heating plate temperature during the drying period. The highest increase in IMP (22.17%) and FAA content (34.54%) compared with the fresh fillets as well as the best color were observed in CFVD fillets. As to the carbonyl compounds, the major contributors to the odor and flavor of fresh fillets, the amount and types were the largest in HAD fillets, while the HAD fillets showed the significant browning. Therefore, CFVD is an effective method to control browning and increase the taste of fillets compared with HAD and VFD. Practical Applications Fish is a greatly perishable product because of its high protein content. Drying has been shown to be an efficient method of conservation. Controlled freezing‐point vacuum drying (CFVD) has been developed. In this study, the key technology challenge of CFVD and its effect on color and flavor of fillet, as well as the differences among the hot air drying and vacuum freeze drying, have been studied. The result shows that CFVD enables best quality in appearance and taste, which is quite helpful to establish an optimal drying condition for a more nutritious and high‐quality dried products.

Label-free based proteomics revealed the specific changes of muscle proteins in pike eel (Muraenesox cinereus) under cold stress

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Nonvolatile taste compounds of Shanghai smoked fish: A novel three stages control techniques

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Evaluation of Aroma Characteristics of Dried Shrimp (Litopenaeus vannamei) Prepared by Five Different Procedures

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