To study the effect of drying methods on rehydration properties of the dried oyster, the fresh oysters were divided into three groups, direct freeze drying (Fresh + FD>. Freeze drying after boiling pretreatment (Boiled + FD) and natural drying group( Fresh + ND), respectively. Drying ratio, rehydration ratio, rehydration percentage and microstructural differences were investigated. The results showed that the water content of the two freeze-dried groups was far lower than the Fresh+ND oysters. And the two freeze-dried oyster groups both had a higher rehydration ratio and rehydration velocity than the Fresh+ND oyster in water bath at room temperature and 100 ℃ .suggesting that freeze drying facilitated the oysters for waterremoval and rehydration. The effect of drying method on the adduct muscle's structure was in a superior to inferior order: Fresh+FD> Boiled + FD>Fresh+ND. The adduct muscle fibre of Fresh + FD was slender, and stretched with well-distributed interfibrillar gaps, whereas the tissue of Fresh + ND group was compacted with aggregated muscle fibres. After rehydration at room temperature for 80 min, rehydration coefficient and rehydration percentage of the two freeze-dried oyster were higher than that of naturally dried oyster.%研究牡蛎冷冻干燥后的复水特性,将新鲜牡蛎分为直接冻干组(Fresh+ FD组)、预煮处理后冻干组(Boiled+ FD组)和自然干燥组(Fresh+ ND组),考察干燥后牡蛎的干燥比,复水比、复水率和微观结构的差异.结果表明:两冻干组牡蛎的含水量远低于自然干燥组,在常温和沸水中的复水比和复水速率均大于自然干燥组,冷冻干燥更有利于牡蛎中水分的去除和复水；干燥后牡蛎闭壳肌微观形态优劣程度依次为Fresh+FD组＞Boiled+ FD组＞Fresh+ ND组,其中Fresh+FD组闭壳肌纤维细长、舒展,间隙均匀,Fresh+ ND组闭壳肌纤维束堆叠,组织致密:常温复水80 min,两冻干组牡蛎的复重系教和复水率均高于自然干燥组.
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