STUDY ON THE DEVELOPING PROCESS PROCESSING RED PEPPER BY FREEZE DRYING METHOD COMBINED WITH INFRARED RADIATION

Abstract

Quang Tri province is a locality with favorable natural conditions for growing pepper. Pepper in Quang Tri province is very popular in domestic and foreign markets because the pepper is small, solid, with a characteristic aroma and spicy taste. Common chemical components in pepper are essential oils and alkaloids. Essential oils, alkaloids, bioactive compounds and pigments of pepper fruits are very susceptible to change and loss during the drying process. Therefore, the goal of this study on the develop process processing red pepper by freeze drying method combined with infrared radiation to limit that change. The experiment was conducted according to 5 formulas with different technical parameters. Analyze and evaluate the nutritional, microbiological and sensory indicators of the product in these 5 formulas, thereby selecting a suitable formula to develop process processing. The process processing is carried out with a wind speed of 1.5 m/s, a drying temperature of 35^oC, the appropriate thickness of the raw material layer on the drying tray is 18.6 mm (three layers), the distance between the infrared lamps is 10 cm, the drying time for each batch of red pepper is 39 hours and 15 minutes, the humidity reaches 12 - 13%. The product after drying has an essential oil content of 2.56%, an alkaloid content of 0.07%, no mold is detected, the product has a reddish yellow color, a characteristic aroma, a characteristic spicy taste and a less wrinkled shell.