三种类型烟叶五年贮藏过程中TSNAs及其前体物含量变化趋势分析

摘要

以调制后的2种烤烟、2种白肋烟以及1种晒烟为试验样品,在5年自然贮藏过程中,定期取样测定不同类型烟叶内TSNAs和其前体物生物碱、硝酸盐含量.研究表明,随贮藏时间增加,5种烟叶NNN、NNK、NAB、NAT和TSNAs总量均不断上升,经拟合符合二次曲线增长模型.白肋烟TSNAs的含量最高,贮藏过程中增加量最多,且以四川白肋烟NNN和TSNAs总量增加幅度最大,其次是晒烟,烤烟TSNAs含量最低,且在贮藏过程中增加幅度较小.TSNAs前体物生物碱及硝酸盐含量在贮藏过程中呈下降趋势,以晒烟的烟碱含量最高且下降幅度较大,以四川白肋烟降烟碱含量最高且下降幅度最大.硝酸盐含量在不同类型烟叶间差异大,白肋烟硝态氮平均含量3076.50μg/g,比烤烟的28.05μg/g高109.68倍.烟叶TSNAs含量与生物碱和硝酸盐相关性均较高,其中硝酸盐含量与贮藏后TSNAs含量的相关性比贮藏前更大,与TSNAs形成更为密切.%Samples of two fl ue-cured tobaccos, two burley tobaccos and one sun-cured tobacco were collected regularly to investigate changes of TSNAs, alkaloid and nitrate content during storage under natural conditions for 5 years. Research showed that NNN, NNK, NAB, NAT and total TSNAs contents of 5 tobaccos increased as storage time increased and the change fitted in quadratic curve model. TSNAs content in burley tobacco was the highest, followed by sun-cured tobacco and flue-cured tobacco and the change was most obvious. TSNAs content was significantly increased in Sichuan burley tobacco, compared with that in Yunnan burley tobacco. It showed non-increase after storage and that the diff erence of fl ue-cured tobacco in two areas were not obvious. Alkaloid and nitrate contents decreased during storage. Nicotine content of sun-cured tobacco and the nornicotine content of burley tobacco was the highest and decreased signifi cantly. Nitrate contents of diff erent types of tobacco were extremely variable, average content of burley tobacco was 3076.50μg/g, 109.68 times higher than that of flue-cured tobacco. TSNAs content of tobacco leaves during storage was correlated with alkaloid and nitrate, and nitrate which was more closely related to TSNAs content after storage than that before storage was more closely associated with TSNAs formation.