类芽孢杆菌发酵原料浸提液提升再造烟叶品质

为提升再造烟叶品质，利用烟草中分离的类芽孢杆菌制备静息细胞，对再造烟叶原料浸提液进行发酵处理；采用连续流动分析、气质联用仪（GC-MS）、热裂解-气相色谱质谱（Py-GC/MS）等方法，测定了发酵过程中浸提液中蛋白质、还原糖、氨基酸含量变化；分析了其主要挥发性香味成分；并利用发酵浸提液浓缩涂布制备再造烟叶样品，进行热裂解产物分析和感官评价。结果表明:①发酵浸提液和对照组中的蛋白质、还原糖含量在5 h内持续减少，而氨基酸含量先增高后降低，且发酵浸提液的蛋白质、还原糖含量低于对照，氨基酸含量高于对照；②发酵液中香味物质种类和总量较对照组均有所增加，其中糠醛、糠酮等致香组分增幅明显；③对比再造烟叶裂解产物，发现发酵浸提液浓缩后涂布样品裂解产生的γ-丁内酯、2，3-二氢-5-甲基呋喃、糠醛等典型烟气致香组分提高；④发酵液浓缩后涂布的再造烟叶样品感官品质较对照样品明显提升。利用类芽孢杆菌发酵烟草浸提液，对于提升再造烟叶的感官品质具有促进作用。 

Improving quality of reconstituted tobacco via fermenting extract of its raw material with Paenibacillus sp.

In order to improve quality of reconstituted tobacco, resting cells of a bacterium Paenibacillus sp.isolated from tobacco leaves were used for the fermentation of tobacco extract during production of reconstituted tobacco.Different analytical methods such as continuous flowing analysis, gas chromatography mass spectrometry (GC/MS) and pyrolysis gas chromatography mass spectrometry (PY-GC/MS) were applied.Contents of protein, reducing sugar and amino acid in tobacco extract was monitored, and its flavor ingredients were detected.Reconstituted tobacco was prepared by coating concentrated tobacco extract fermentation broth.Pyrolysis product analysis and sensory evaluation of final reconstituted tobacco was also carried out to assess effect of bacterium fermentation.Results showed that: 1) In 5 hours, contents of protein, reducing sugar in tobacco extract reduced while amino acid increased first and then decreased.Nevertheless, the fermentation tobacco extract(adding Paenibacillus sp.) featured lower contents of protein and reducing sugar but higher contents of amino acid than control tobacco extract(without adding Paenibacillus sp.).2) Compared with control tobacco extract, the species and quantities of aroma compounds in fermented tobacco extract were higher, among which furfural aldehydes and keltones were increased.3) Aroma compounds of pyrolysis products, such as 4-Butanolide, 2, 3-Dihydro-5-methyl- Furan, Furfural were increased in final reconstituted tobacco coated with fermentation tobacco extract.4)Compared with control reconstituted tobacco, sensory quality of final reconstituted tobacco coated with fermentation tobacco extract were also improved.Thus, tobacco extract fermentation by Paenibacillus sp.during production process could increase final quality of reconstituted tobacco.