Impact of ultrasound-assisted osmotic dehydration as a pre-treatment on the quality of heat pump dried tilapia fillets

The dehydration of a tilapia fillet is conducive to its preservation. However, dehydration results in high energy consumption and quality variation. Ultrasound-assisted osmotic dehydration as a pre-treatment combines the advantages of strong permeability by preservatives and the cavitation effect and can improve the quality of tilapia fillets dried by heat-pump drying while decreasing the drying time and maintaining the quality of the dried products. The whiteness, texture, rehydration rate, Ca2+ adenosine triphosphate synthase (Ca2+-ATPase) activity and the comprehensive score were used as criteria in single-factor experiment son ultrasound power, ultrasonication and permeate concentration. Based on the results of the single-factor experiment, the Box-Behnken central composite design was adopted to achieve response-surface optimisation. The results indicated Ultrasound-assisted osmotic dehydration as a pre-treatment with suitable ultrasound parameters can significantly improve the quality of heat-pump dried tilapia fillets and provides references for optimising the drying process.