Feasibility of high-intensity ultrasonic blanching combined with heating for peroxidase inactivation of seedless guava (Psidium guajava L.)

Enzyme inactivation of seedless guava was performed by using conventional and high-intensity ultrasonic blanching. The conventional blanching was performed by application of hot water in the temperaturerange of 80-95 °C and time needed for peroxidase inactivation was determined. pplicability of highintensityultrasonic blanching for inactivation of peroxidase enzyme was investigated in this study at the same range of the temperature. The application of high-intensity ultrasonic blanching processes promotedenzyme inactivation at a higher rate (P<0.05), when compared with the hot water blanching processes. These results allow the application of high-intensity ultrasonic blanching with shorter blanching times at this range of temperatures. Therefore, the ultrasonic treatments can be an alternative to the conventional hot water blanching processes that enable less severe thermal treatments and, improving the quality of theblanched product. The present findings will help to design the blanching conditions, with minimized physico-chemical and nutrient changes of final product

Keywords:

Blanching , high-intensity ultrasound , peroxidase inactivation , seedless guava