Effects of osmotic dehydration vacuum-microwave drying on the properties of tilapia fillets

Abstract

A novel drying method based on vacuum-microwave dehydration was developed to investigate the effects of different microwave gap ratios (MGR), microwave times, power densities and degrees of vacuum after osmotic pre-treatment on tilapia fillets. The results showed that the moisture value of fillets was decreased with the increased drying time, power density and vacuum degree. The shrinkage ratio, rehydration ratio and total colour change increased with elevated microwave time and power density. A high degree of vacuum was beneficial to the qualities of fillets. In conclusion, tilapia fillets retained their original quality properties after osmotically dehydrated vacuum-microwave drying (OD-VMD); optimum process parameters were MGR = 2, microwave time = 10 min, power density = 20 W/g, and vacuum degree = 0.08 MPa.