Study On Key Technologies Of Continuous Processing Of Needle Premium Green Tea

Needle premium green tea is a kind of needle tea, which is dependent on special rolling process. In order to improve the production efficiency of tea enterprises, promote the standardized and scale of neeld green tea. the experiment for the process of needle premium green tea by means of a complete set of continuous production line, it including the YJY-EM-110 fresh tea leaves artificial spreading machine, DXCWS-15electromagnetic heat roller fixation machine,6CLXL11/8 continuous bedding article machine,6CHZ-2rubbing machine,6CLXL8/8 one-stage continuous fixation-shaping machine,6ccp-110roller type roasting machine. Using this continuous production line, the processing technology of needle premium green tea was explored and studied.The major findings are as follows:It can effectively improve the quality of tea by the fresh tea leaves artificial spreading system, the density of fresh leaves is 1.0±0.1 kg-m-2, it were spread at 18 ? to 20 ?, and the relative humidity levels is about 90±5%, then turn on external ventilation to hold the concentrations of carbon dioxide between 410 to 450 mg·L-1, the environment temperature should retain at 20 to 24degree centigrade, and the relative humidity levels is about 75±5%, if the leaves were wash by rain, we also develop a mathematical models by moisture loss over time to determine how long will makethe moisture content of leaves at 68% to 70%. The conclusion is that single bud takes about 10 to 14 hours and a bud with a leaf takes about 6 to 10 hours.The main technology parameters during manufacture process is that the tea leaves is deactivated of enzymes at 270±2?for 65±5 s and at a microwave temperature control at 150? for 20 to 30 seconds, then through a multistage continuous fixation-shaping machine with the first temperature at 240 "C/38 Hz, second temperature at 210?/40 Hz and third temperature at 180?/45 Hz to make the needle shape, and control tape condenser temperature at 120?/48 Hz, then keeping the leaves in a temperature at 140? to 160? for 12 minute to control leaves moisture content at 15-18%, finally drying out at 45-55? to reserve moisture proportion between 6-7%.The DXCWS-05 far-infrared raising fragrant machine finally use to improve tea quality,that initial processing parameters set with a original temperature at 90 to 110 ? for 60 to 100 second, then thetechnical parameters was optimized by using Box-Behnken response surface methodology. We finally determined that baking at 99.09 degrees centigrade for 85.19 second with relative humidity levels at 75.09% earn the highest score of 94.8.