Drying Properties and Parameters of Blue Honeysuckles Pulp under Foam Assisted Microwave Drying Conditions

Abstract

The drying properties and optimal parameters of foamed blue honeysuckles pulp under microwave drying conditions were studied. The microwave power, loading mass and thickness were selected as the influencing factors, and objective factors were content of anthocyanin, vitamin C, moisture and values of color of the final blue honeysuckles powder. The drying process may be divided into three stages: acceleration stage, slow decline stage and quick decay stage. The initial drying phase lasted until the moisture content was less than 4 kg/kg. The constant drying phase was long when the influencing factor was loading mass. The deceleration drying phase is short in all conditions. This study achieve the continuous production of blue honeysuckles powder and the optimum experiment parameters were obtained as follows, the content of anthocyanin in honeysuckle powder is 64.58 mg/g, the content of vitamin C is 14.604 mg/g, moisture ratio is 9.88 % and the color value is 9.78 with the microwave power at 8.86 kW, loading mass at100 g and the thickness at 4mm.