Optimization of heat pump drying technical parameters of salted dry fish

To improve the traditional drying technology of salted dry fish, we investigated the dry curve and dry process parameters of salted fish under different heat pump drying conditions. Taking chromatism and sensory evaluation as indices, we studied the drying temperature, humidity and wind speed which affect drying process of salted dry fish, so as to determine the best process parameters in heat pump dry process through orthogonal experiment. The optimal parameters were as follows: heat pump temperature 30 ℃, relative humidity 30% and wind speed 1.5 ms-1. The chromatism value of salted dry fish was 2.68 and the sensory score was 88.7 under these conditions. Salted dry fish after heat pump drying had smaller chromatism, better quality and less fat oxidation with peroxide value of 0.135 mgkg-1 compared with fresh fish. The quality of salted dry fish was improved.