Physical and sensory properties of heat pump dried shrimp (Pandalus borealis)

The peeled, headed and whole shrimps (Pandalus borealis) were dried in a heat pump dryer at (-2～0)℃ and 20℃. Physical and sensory properties of heat pump dried shrimp were evaluated. The shrinkage and shear force in cutting the dried shrimp samples increased with the drying temperature from (-2～0)℃ to 20℃. The color values of dried shrimp were not remarkably affected by the drying temperature. All the shrimp dried by heat pump at (-2～0)℃ and 20℃ had high rehydration ratio and water holding capacity (WHC). The results also show that the physical and sensory properties of dried shrimp are significantly affected by the handling conditions (with shell or shelled, with head or headed, and the thawing process) of shrimp. The thawing process increases the shrinkage and adversely influences the color of dried shrimp. The frozen headed shrimp dried at 20℃(B-2) has the best synthetic performance among all the dried shrimp samples. Comparing with hot air drying, heat pump drying is a promising drying method for high quality shrimp product drying.