| For study the influence of wind speed in different stages of bulkcuring to cured tobacco leaves quality, the thinking of single test combined withintegrated compliance test had been adopted during2009-2010to conduct ventilationtest in yellowing stage during the bulk curing and in later bulk curing process and instem-drying stage, meanwhile optimization bulk curing technology test to beconducted.The main results are as follows:(1) From the proceeding of curing to constant temperature of38℃ending,when fan speed was1440r/min, starch contents of tobacco leaves was15.21%andthe rate of starch degradation was faster, the relatively high content of reducing sugarwas9.84%.The end of constant temperature of38℃, the fan speed was960r/min, therate of starch degradation was faster than treatment of1440r/min, and the content ofreducing sugar was relatively high. The starch contents of tobacco leaves based on fanspeed960r/min was lowest, which had not significant difference compared with fanspeed720r/min and1440r/min. The reducing sugar contents of tobacco leaves basedon fan speed960r/min was highest, which was25.34%and had significant differencecompared with content based on fan speed720r/min and1440r/min. Chlorophyll aand Chlorophyll b content of tobacco leaves based on fan speed960r/min inyellowing stage of bulk curing was significantly lower than content based on fanspeed720r/min and1440r/min,6.17μg/g and3.27μg/g respectively, carotenoidcontent was138.83μg/g,which was significantly lower than content based on fanspeed1440r/min. The total volatile aroma of tobacco leaves was highest when the fanspeed was960r/min.(2) During temperature of47and ending of content temperature of54, thestarch contents of tobacco leaves would be decreased and the reducing sugar contentswould be increased when the fan speed was960r/min, meanwhile, starch contentswas significantly lower than other experiment treatment of1120r/min and1440r/min,reducing sugar contents was significantly higher than others, there was no obviousdifference during starch contents based on the same fan speed. In the later stage of fixing-color, the starch contents of tobacco leaves, the fan speed960r/min, wassignificantly lower than other experiment treatment of1120r/min and1440r/min,reducing sugar contents was significantly higher than others, and reducing sugarcontents was significantly high form later stage of fixing-color to drying stage withfan speed form960r/min change into720r/min. When the fan speed sat at960r/minin the later stage of fixing-color and720r/min in the drying stage, Chlorophyll a andChlorophyll b content at end of54℃were lowest; carotenoid content was no obviousdifference when the leaves curing was in the same fan speed, if the fan speed wasdifferent, carotenoid content was obvious difference, including carotenoid content waslowest when the fan speed was960r/min.960r/min of fan speed in the later stage offixing-color was significantly lower than1120r/min and1440r/min at carotenoidcontent of tobacco leaves, and carotenoid contents were no obvious differencebetween1120r/min and1440. Neophytadiene and octacosane total content and totalvolatile aroma were highest when the fan speed was960r/min in the later stage offixing-color and720r/min in the drying stage, meanwhile smoking scores washighest.(3) Neophytadiene content and every volatile aroma were highest when the fanspeed was720r/min in the whole drying stage.(4) At the end of38℃, the content of starch degradation and reducing sugarcontents in the ventilation optimization technology were lower than those in1440r/min of fan speed, but since temperature of42, the results were opposite, andsince the end of47℃, the content of starch in the ventilation optimization technologywere lower than those in1440r/min of fan speed, the content of reducing sugar wasopposite. As for chemical Constituents, nitrogen compounds content of optimizationtechnology tobacco leaves was lower than what in1440r/min of fan speed, the resultof carbohydrate content was opposite. The ratios of carbohydrate to alkali ofoptimization technology tobacco leaves nearly was10and the ratio of potassium tochlorine was higher.The results indicated that chlorophyll a and chlorophyll b contents in thethree-speed circulating ventilator treatment were92.49%and95.47%of that of thesingle-speed treatment while Lutein, β-carotene and carotenoid content were86.40%,95.53%and95.47%of that in the single-speed treatment. Chlorophyll a/b contens inthe three-speed circulating ventilator treatment were77.20%, Car/Chl in thethree-speed circulating ventilator treatment were103.12%. Chlorophyll a, Chlorophyll b and the ratio of Chlorophyll a to Chlorophyll bwhich of optimization technology tobacco leaves and CK tobacco leaves wereobvious difference, β carotene and carotenoid content of them were very significant,however the ratio of lutein to carotenoid was no obvious difference; Sensory qualityof optimization technology tobacco leaves was superior to CK tobacco leaves,especially amount of aroma.The result show that: the starch of tobacco leaves were lower and pigmentcontents of tobacco leaves were higher,contents of aroma constituents were morewhen the fan speed was1440r/min within2hours after curing in yellowing stage,then fan speed had been960r/min since constant temperature of42ending, in thestage of fixing-color, fan speed was1440r/min at end of constant temperature of42～47, and960r/min of fan speed at end of constant temperature of47～54; fan speedsat at720r/min from temperature of54to curing ending. |
