Effect of vacuum drying and pulsed vacuum drying on drying kinetics and quality of bitter orange (Citrus aurantium L.) slices

摘要

The effect of vacuum pressure (20.0, 17.5, 15.0, 12.5, and 10.0 kPa) of vacuum drying(VD) and vacuum pressure (20.0, 15.0, and 10.0 kPa), drying temperature (65, 70,and 75 °C), and the ratio of pulsed vacuum (5:10, 5:15 and 5 min:20 min) of pulsedvacuum drying (PVD) on drying kinetics and quality (rehydration rate and color differenceL*, a*, b*, ΔE, and BI) of bitter orange slices (4 mm) were investigated experimentally.Drying bitter orange slices by PVD can effectively increase the drying rateand decrease quality degradation. The optimal condition was 75 °C, 10.0 kPa and5 min:15 min, which decreased 47.6%, 28.3%, and 15.5% of the moisture ratio, ΔEand BI than VD. Compared with APD, the moisture content undergoing PVD for 4 hrdecreased 72.9%. The Third-degreepolynomial drying model was the most suitable(R2 of 0.99865) for PVD.