STUDY ON DETERMINATION OF HEAT PUMP DRYING MODE FOR MANUFACTURING RED PEPPER
STUDY ON DETERMINATION OF HEAT PUMP DRYING MODE FOR MANUFACTURING RED PEPPER
Red pepper is one of the special products made from ripe and high quality pepper fruits. Because of its high quality, red pepper is often sold at much higher price than that of black pepper, which brings farmers high incomes. However, at present, processing technology of red pepper in Vietnam is not completed yet. Red pepper has been mainly produced by using natural drying method. As the result, the quality of products is low, the color of peppercorns is not satisfactory and its taste is not really different compared with other pepper products. The method of heat pump drying being widely used in the processing of agricultural products and foodstuffs to keep color and quality of the products (especially for products are easily destroyed by heat like vitamins). Research on red pepper production by applying the method of heat pump drying has been conducted by WASI since 2017. The best heat pump drying regime was dertermined as: Temperature at 350 C, relative humidity at 40%, wind speed at 3 mps, drying time in 36 hours. The red pepper retained natural color of ripe beans. The flavour and the quality of dried red pepper products were better than that of control samples. Besides, the treatment of raw material was processed by hot water at 900 C in 1 minute before drying is able to improve quality of red pepper products.