【作者】 张娟；

【导师】 张晓鸣；

【作者基本信息】 江南大学 ， 食品科学， 2008， 硕士

【摘要】 烟草是重要经济作物,病虫害种类多,危害严重。贮烟霉变现象导致的报废和贮烟质量的降低是烟叶仓贮期必须重视的问题;防治贮烟霉变是储烟综合治理的重要内容。本文通过合成富马酸二甲酯作为烟草防霉剂,取得了良好效果。首先对富马酸二甲酯的合成工艺及分析方法进行了研究。确定了富马酸二甲酯的最佳合成工艺条件。采用硫酸氢钠为催化剂,用氧化钙为吸水剂,当酸醇摩尔比为1:10,催化剂添加量为富马酸质量的15%,反应温度75℃,搅拌速度136r·min-1,回流5h,所得酯产率达到74.9%。所得产物经分离纯化后,用紫外和红外光谱分析,在210nm处有最大吸收峰,所得红外图谱与标准富马酸二甲酯红外图谱对照后,可知产物为富马酸二甲酯。采用高效液相色谱作为定量分析方法,条件为:色谱柱Zorbax SB-C18 (5μm,250mm×4.6mm i.d) ,流动相乙醇/水(90:10,v/v),流速0.6mL·min-1,柱温30℃,检测波长210nm,进样量15μL,UV检测器。富马酸二甲酯在该检测条件下的保留时间为5.335min。初步鉴定储烟霉菌为4个属:青霉属,根霉属,曲霉属及毛霉属。分别是半知菌亚门青霉属扩张青霉(P.expansum),匐枝青霉(P.stoloniferum Thom),根霉属米根霉(R.oryzae Went et Pr.Geerlings),曲霉属黑曲霉(A.niger),局限曲霉(A.restrictus),接合菌亚门毛霉属总状毛霉(M. racemosus Fres)。由富马酸二甲酯对各霉菌的抑菌性实验可知,富马酸二甲酯对扩张青霉的抑制效果最好,对米根霉的抑制效果最差,但在较低的浓度可以全面抑制各种菌的生长。富马酸二甲酯的抑菌效果受到温度的影响,对pH适应范围较广,受到自身挥发性的影响较大。由富马酸二甲酯直接添加法防霉实验,可知烟叶含水量为18%时,添加500 mg·kg-1的富马酸二甲酯对储藏片烟能起到有效的防霉效果。烟叶含水量为13%时,添加或不添加富马酸二甲酯到120d时均不会发生霉变。在对烟叶防蛀的实验中,可知富马酸二甲酯不仅可以防止烟叶虫蛀,还可以在很大程度上杀灭蛀虫。经感官评吸,可知在500-1500mg·kg-1的添加量范围内,富马酸二甲酯的添加对烟叶的感官品质基本上无不良影响。通过对添加富马酸二甲酯的卷烟烟气进行GC-MS分析,发现添加富马酸二甲酯的卷烟烟气成分及其对照样的GC-MS分析中均未检出富马酸二甲酯,可认为样品中无富马酸二甲酯释出。采用气相色谱法,对富马酸二甲酯在储藏烟叶上的残留量进行检测。发现添加量为500 mg·kg-1时,经过卷烟加工工艺的烟叶上没有残留,而添加量为1500 mg·kg-1时,烟叶上的残留量仅为0.0752 mg·kg-1,添加在烟叶中的富马酸二甲酯基本已全部挥发完。总之,在烟叶中添加富马酸二甲酯作为防霉剂非常安全且对烟叶的感官品质及常规指标不会有不良影响。更多还原

【Abstract】 Tobacco is an important economic plant which has been badly destroyed by tobacco disease and mildew. The quality decreasing and breakage of tobacco caused by tobacco mildew is a crucial problem which must be attached importance to. Mildew controlling is an important part of general treatment of stored tobacco. In this dissertation, Dimethyl Fumarate was synthesized to be used as the fungicide on stored tobacco mildew which was proved to be highly effective.The synthesis condition and analysis method were studied first in this dissertation. The condition of synthesis of Dimethyl Fumarate was optimized. Sodium bisulfate was picked as the catalyst in the condensation reaction of fumaric acid and methanol. Using calcium oxide as the desiccant was an effective method of removing water from the methanol esterification. The molar ratio between fumaric acid and methanol was 1:10, usage of catalyst was 15% of fumaric acid, the reaction was carried out at 75℃as the churning rate was 136 r·min-1, refluxing for 5h, the yield was up to 74.9%. The product was analyzed by UV and IR right after purification. A peak was found at 210nm, comparing the IR spectra to the one of pure DMF, DMF was identified. High performance liquid chromatography (HPLC) was used to analyze the quantity of DMF. Chromatogram with high resolution was obtained using the column of Zorbax SB-C18(5μm,250mm×4.6mm i.d) with a UV detector and the mobile phase of ethanol: water 90:10v/v at a flow rate of 0.6 mL·min-1 at 30°C and 210nm of detecting wavelength.The fungi separated from stored tobacco were identified as species of Aspergillus, Penicillium, Rhizopus, Mucor. They were M. racemosus Fres, P.stoloniferum Thom, R.oryzae Went et Pr.Geerlings, A.niger, A.restrictus and P.expansum respectively.The results of mildew-preventing experiment showed that the inhibition effect of DMF against P.expansum was optimal while to R.oryzae Went et Pr.Geerlings it was worse. DMF could inhibit the growth of all fungi at a certain concentration. Its effect could be affected by temperature, pH and the votality itself. At the moisture content of 18%, DMF was effective in mildew-preventing at the concentration of 500 mg·kg-1, it also had favorable moth-preventing effect at a certain concentration. So DMF could be used as an effective fungicide and mothproofer in tobacco storage.Affect of addition of DMF on the sensory characteristics of cigarette were tested by 12 experts. The results showed that when the amount was at the range of 500-1500mg·kg-1, the addition of DMF had no effect on the sensory quality of cigarette. From the GC-MS results of mainstream smoke analysis, no DMF was detected either in the cigarette which were added DMF or not, so it was thought that no DMF was released. The residual DMF on stored tobacco were detected by gas chromatography. The results showed that there was no DMF left in the tobacco which had been treated using the general process when the addition amount was 500mg·kg-1.When the amount went to 1500mg·kg-1, the residual DMF was only 2.21mg·kg-1 , most of which had been volatilized.Above all, using DMF as the fungicide was safe and there was no influence both on the sensory charactertics and the general index of cigarettes.更多还原