| In order to explore the best flue-cured tobacco curing mode and curing process, inverter used in this experiment to dug the circulation fan of frequency conversion in bulk curing barn. Different fan variable frequency adopted in different curing stage during curing process in bulk curing barn in the test , ventilation, temperature, humidity conditions, tobacco physiological and biochemical characteristics and the neutral aroma components in cured leaf, exterior physical traits and intrinsic chemical quality and the comparison of the economic characters during baking, the fan speed conditions were preliminarily defined in different curing stage on the density of 65kg/m3, and the internal flow field of humid environment and tobacco physiological and biochemical characteristics and the influence of roast tobacco leaf quality, the main conclusions are as follows:1 Effects on the field environmentThrough the comparison between different processing, dispose and contrast in different curing stage between temperature and humidity and the difference between wind speed of tobacco leaves, it is concluded that the treatment and controlled in turn yellow stage humidity and temperature is no difference, 960 r/min of rotation speed can satisfy the requirement. 1145 r/min of rotation speed can decrease the difference of humidity and temperature in fixed color phase, that is to say the wind speed at 0.35m/s can better optimization about humid flow field in the internal environment. And when 960 r/min exhibited platoon is wet evaporate dehydration can't keep pace with tobacco, killing curing speed tobacco leaf hangs ash and flower piece phenomenon. The Practice showed that the dry muscle stage curing the 720r/min of rotation speed can satisfy the requirements of baking.2 Effects on tobacco physiological and biochemical characteristicsAmylase activity in the 1450 r/min of rotation speed is higher when temperature at 42℃and 48℃, from the analysis of PPO,SOD,POD and MDA, on the plasma and can be concluded that the 1,450 r/min of rotation speed processing can keep SOD and POD higher activity, PPO remain low, reduce the cargoes of MDA.Enzyme activity already basic terminated when the temperature reach 54℃, the fan rotation speed at 720 r/min,SOD can still keep higher during the process, the content of MDA is low. And 960 r/min of rotation speed will make more low in humid, making SOD activity reduced. Different fan speed treatment on the influence of pigment degradation is not obvious. Carotenoids will get more when the temperature at 42℃, the fan rotation speed reach 1,450 r/min, there is no difference between other temperature points of every treatment , chlorophyll are not quite apparent in the roasting process. 3 Effects on the of chemical composition and physical property of tobacco leafThe test results show that using different span speed in different baking stage have significant influence of the content of neutral aroma components. Including T2 (the 1450 r/min of rotation speed when the temperature was between 42℃and 54℃, and 720 r/min afterward) the content of neutral aroma reach the highest amount of matter; T1 (the 1450 r/min of rotation speed when the temperature was between 42℃and 54℃, and 960 r/min afterward)dispose the quantity of neuter aroma is lower; T3 (the 960 r/min of rotation speed when the temperature was between 42℃and 68℃), T4 (the 960 r/min of rotation speed when the temperature was between 42℃and 54℃, and 720 r/min afterward) treatment, the amount of carotenoid, browning reaction products and cembratriendiol group were extremely significant low than controls.The treatments of conventional chemical composition and physical property analysis results show that T1 (the 1450 r/min of rotation speed when the temperature was between 42℃and 54℃, and 960 r/min afterward) and the control treatments physical properties are better. T1 (the 1450 r/min of rotation speed when the temperature was between 42℃and 54℃, and 960 r/min afterward) and T2 (the 1450 r/min of rotation speed when the temperature was between 42℃and 54℃, and 720 r/min afterward) appearance quality are better, the chemical composition more coordination, and T3 (the 960 r/min of rotation speed when the temperature was between 42℃and 68℃) and T4 (the 960 r/min of rotation speed when the temperature was between 42℃and 54℃, and 720 r/min afterward) are relatively poor.4 Analysis on the economic characters and appropriate air flow velocity between leaves of tobaccoThe analysis result of the economic characters of various treatments, frequency conversion process is difference from that of the control in coal consumption; each frequency processing were significantly lower than controls in electricity consumption, and the difference value were between 0.29 kWh/kg and 0.31 kWh/kg; Application of frequency conversion technology can reduce curing cost, have the certain income effect.we found that tobacco leaves turn yellow stage between the wind plus or minus 0.05 m/s; leaf drying stage leaves wind between 0.35±0.12 m/s; Dry wind reinforced stage was 0.40±0.17 m/s, which is about the curing process relatively appropriate leaves wind, these treatment gap after baking the comprehensive quality external appearance of the good, the color orange, oily cent enough, identity moderate, burnish bright, hairy, even, flavor good. |
PDF Full Text Request