ẢNH HƯỞNG CỦA XỬ LÝ NATRI METABISULFITE VÀ NHIỆT ĐỘ ĐẾN CHẤT LƯỢNG SẢN PHẨM RAU MÙI SẤY (CORIANDRUM SATIVUM)

Abstract

Coriander (Coriandrum sativum) is an herb in the Apiaceae family with an important
characteristic that high levels of polyphenols are present with antioxidant activity. In this
study, coriander leaves and stem were subjected to dipping in sodium metabisulfite solution of 100 to 400 ppm in 1 to 4 minutes. The effect of air temperature (50-800C) on moisture content of coriander was studied experimentally and four common drying models
were developed, based on data obtained. The total polyphenol content and antioxidant activity by free radical (DPPH) method of dried coriander leaves and stem were also measured. The best color of dried coriander leaves was obtained by dipping coriander leaves
in 200 ppm sodium metabisulfite for 2 minutes. The treated coriander leaves and stem
were dried at 700C for better quality (total polyphenol content of 66.81±0.687 mg/g in dry
weight) than the rest samples. The assessment of radical scavenging activity DPPH
(75.23±0.88%) showed an increase in scavenging effect particularly at this drying. In addition, experimental data was fitted to four thin-layer drying models. The Page drying
model was found to satisfactorily describe and predict than the others ( R2>0.9) for dried
coriander leaves. The drying kinetics of coriander leaves and stem were also established.