Abstract: The effects of natural-air drying, hot-air drying and vacuum freeze-drying on the quality and microstructure of cuttlefish were investigated. Quality parameters such as sensory quality, color, shrinkage ratio, texture, flavor and formaldehyde content were determined and the rehydration ratio of dried cuttlefish and the changes in some texture parameters after rehydration were examined. The results showed that the shrinkage rates of dried cuttlefish produced by various drying methods were in the decreasing order of natural-air drying > hot-air drying > vacuum freeze-drying, with significant differences being observed among these (P < 0.05). Vacuum freeze-dried cuttlefish were better than the other two groups in color and rehydration ratio, showing a rehydration ratio of up to 524.25% at 9 h of rehydration in water, which was 2.5 times as high as that of the natural-air dried samples, but in terms of texture and flavor, the muscle fiber showed a little deformation and loose arrangement. The hot-air dried samples had significant advantages in sensory, texture and flavor characteristics, and the content of taste-active amino acids was 1 519.20 mg/100 g, which was significantly higher than that of the other dried samples (P < 0.05), but the formaldehyde content was 260.83 mg/kg, which was 4.7 times as high as that of the fresh samples. In addition, the muscle fiber had a large deformation and a dense arrangement. In contrast, the formaldehyde content of the natural-air dried samples was the lowest of all three drying methods, which was as low as 22.06 mg/kg. Natural-air drying resulted in a little deformation and dense arrangement of the muscle fiber, and the sensory quality and color of the dried product needed to be further improved.

Key words: drying, cuttlefish, quality, microstructure