The effects of ultrasound as emerging technology along with thermal treatment were investigated on the activity of barley’s alpha-amylase after germination. All experiments were carried out at 20 kHz on an ultrasonic generator by considering the three effective factors, temperature (30, 50 and 70 oC) and ultrasonic intensities (20, 60 and 100% setting from total power of device (460 W)) in different time intervals (5, 10 and 15 min). For determining the effects of these parameters, the enzymatic activity was assayed by measuring the reducing sugars released as a result of the alpha-amylase action on soluble starch using 3,5-dinitrosalicylate regent (DNS). The results of these assays were analyzed by Qualitek4 software by using the Taguchi statistical method to evaluate the factor’s effects on the enzyme activity. Consequently, the results of assays showed that the activity of this enzyme from germinated barley was reduced after thermosonication by comparing to the blank.
De Gennaro L, Cavella S, Romano R, Masi P, J. Food Eng., 39, 401, 1999
Kuldiloke J, Effect of ultrasound, temperature and pressure treatments on enzyme activity and quality indicators of fruit and vegetable juices, Doctoral dissertation, Dept. Food Biotech. and Food Process Eng., Berlin Univ. of Technol. Berlin, 2002
Povey MJW, Mason TJ, Ultrasound in food processing, Ultrasound in food processing, 115, 1998