对不同类型及产地雪茄烟叶pH、总挥发酸和总挥发碱含量进行对比分析,并对三者关系进行偏相关分析.结果 表明,雪茄烟叶的pH、总挥发碱高于烤烟,总挥发酸低于烤烟,3个指标为负相关;不同产地雪茄烟叶pH、总挥发酸和总挥发碱含量差异显著.综上,雪茄烟叶具有高pH和高总挥发碱、低总挥发酸的特点.

采用水中蒸馏法制取香橼皮精油,用无水硫酸钠进行脱水处理,对所得到的精油进行理化指标的测定和香气成分分析,并进行卷烟加香试验.结果表明香橼皮精油能明显改善和修饰卷烟香气,协调烟香,提高卷烟香气品质.

L-citrulline was produced by arginine deiminase from engineering bacteria.Factors which affected the yield of L-citrulline were studied,including culture medium,inducing conditions and cell conversion.The optimum culture were found to be 5 g/L glucose,20 g/L tryptone,1 g/L K2HPO4·3H2O and 1 g/L MgSO4·7H2O.The optimum inducing conditions were found to be the cell OD600 1.0,the temperature 25 ℃,the time 7 h and lactose 5 g/L.Under the optimum cell conditions: the pH 6.0,the temperature 40 ℃,and substrate concentration 60 g/L,55.1 g/L of L-citrulline could be obtained.The cells could be used for 3 times and the yields were stable.The findings in cigarette show that it was the best effect when the amount was 0.02%.

Isotope(deuterium oxide,D2O)tracer method was used to trace the water content in cut tobacco in order to reveal the variation of water transfer in the course of tobacco processing.The cut tobacco obtained from each stage of the processing was dried in a vacuum oven to remove all of the water.It was then loaded into the vacuum line assembly(VLA)in which the same mass of deuterium oxide(D2O)was injected.The diffused D2O was absorbed by the dried tobacco till in equilibrium.The D2O at different stages of the processing were then extracted with the VLA,respectively.The D2O extract was derivatized with acetic anhydride,and analysed by GC-MS to obtain the mole ratio of CH3COOD to CH3COOH,through which the mole ratio of D2O/H2O was obtained.The amount of water lost at each stage of the processing was confirmed.It was found that the loss occurred mainly in the parching process.The result may be useful for the optimization of cut tobacco processing.