Effect Of Withered With Different Light-waves Bands On Physiological And Biochemical Qualities Of Oolong Tea

Withering is one of the most important processes to format the quality characteristics of Oolong tea,it relates to color,fragrance and taste of raw tea. The research of artificial light withering has important significance to promote development of Oolong tea withering , getting Rid of bad weather brings detrimental effects , implementating standardized and continuous production . According to sunshine wethering principle ,the research designs different light waves (Blue light 435～480nm,Red light640～780nm, Hybrid optical360～780nm , Middle infrared1100～2500nm , Far-infrared>2500nm) , different powers(100W,200W,300W,400W)to realize manual intervention withering, discuss different light sources , withering technology influences of physiological and biochemical compositions. Experimental Study on the source technical parameters(light waves and powers) and technological parameters(irradiated distengces and irradiated times), selected the best light sources combinations, the research provides scientific basis for the expliotion of manual intervention withering and technological parameters.1. The reseach results of leaves temperature and moisture content after different manual intervention witherings as follows:(1) On the same distence and time condition,the leaves tempertures changes because of different light sources and powers. The variation order is Far infrared> Middle infrared >Hybrid optical> Blue light >Red light.and the temperture has little difference among visible light treatments,but the difference was significant among unvisible light treatments.The manual withering leaves temperture 29.14℃is above 25.71% than room-withering 23.18℃,this shows that the manual withering has significant effect in increasing leaveas temperature.(2) On the same light waves and power,the red light source leaves temperture varies significantly,but other varies unsignificantly. Irradiation strength increases as the distence reduces.The leaves burn while the diatences is 0.1m,so that we must Strictly control the distence and withering time. (3) On the same distence and time condition,the leaves moisture content changes because of different light sources and powers. The variation order is Red light > Blue light >Hybrid optical> Middle infrared > Far infrared,and the Hybrid optical has significant difference to unvisible light sources.The leaves moisture content a negative correlation to power and average of tempertures.2. The reseach results of leaves enzyme activity and chlorophyll fluorescence parameters after different manual intervention witherings as follows:(1) Polyphenol Oxidase activity raises while the distence reduces and times increasing,the activity constantly increases acording among visible light waves,it first goes up and after down among unvisible light waves.β-glucosidase activity goes up while the diatence reduces. It first goes up and after down when the withering time prolonged,it is the largest when 30min.(2) The reseach of chlorophyll fluorescence parameters shows the photochemical reaction starts most quiCKly,can improve utilization rate of solar energy in a short time.But the leaves are easy to be effected by photo inhibition under big irradiated strength.The study on efficiency of PSⅡreaction center shows that physical effects are the more import the waves longer,and chemical effects are more disimport, and vice versa.3. The reseach results biochemical changes and quality of Oolong Tea after different manual intervention witherings as follows:(1) On the same distence and time condition,the leaves biochemical changes because of different light sources and powers.Blue light and Red light resources are beneficial to improve Oolong tea fresh and feel well digree,reduce the bitterness and astringency. Comprehensive evaluation of the quality is the best, while different light waves sources 300W(Blue light48.63W/m2,Red light47.00W/m2,Hybrid optical 52.78W/m2,Middle infrared176.54W/m2,Far infrared 213.45W/m2 ) ,0.3m,30min.(2) The sensory safety review quality order is Blue light >Red light > Far infrared>room withering Tie Guanyin in autumn. But there were some differences for sensory safety review quality order is Red light > Blue light > Far infrared> room withering Huang Dan in autumn.