四川雪茄烟叶在成熟与晾制和发酵过程中烟草特有亚硝胺的积累动态

为明确雪茄烟叶在成熟、晾制及发酵过程中烟草特有亚硝胺（TSNAs）的积累及变化规律，以德雪3号（茄衣）和什烟1号（茄芯）为试验材料，在烟叶成熟、晾制及发酵环节对两种烟叶的中部叶及上部叶取样，并测定烟叶中的TSNAs含量（质量分数）。结果表明，德雪3号在3个生产环节TSNAs的积累量分别为153.53~208.26、574.10~597.50和647.40~1 090.73 ng/g。什烟1号在3个生产环节TSNAs的积累量分别为305.63~526.81、1 700.45~2 494.93和1 529.60~2 373.37 ng/g。两种雪茄烟叶TSNAs各组分和TSNAs总量在不同阶段积累差异较小，均表现为烟叶成熟前积累较少，调制和发酵阶段积累较多。在晾制和发酵环节茄衣品种德雪3号TSNAs总量的积累比例分别为30.65%~42.73%和46.29%~58.23%，茄芯品种什烟1号TSNAs总量的积累比例分别为45.26%~48.22%和40.71%~45.87%。随着烟叶晾制和发酵过程的推进，烟叶TSNAs含量呈现逐渐增加的趋势。因此，晾制和发酵时期是雪茄烟叶TSNAs积累的重要时期，也是调控其积累的关键时期。 

Dynamic accumulation of TSNAs in Sichuan cigar tobacco during mature,air-curing and fermentation

To clarify the rules behind accumulation and variation of tobacco specific nitrosamines (TSNAs) in cigar tobacco leaves at mature, air-curing and fermentation stages, the middle and upper leaves of cv. Dexue 3 (cigar wrapper) and cv. Shiyan 1 (cigar filler) were sampled at the above three stages and their TSNA mass fractions were determined. The results showed that the TSNA accumulations of Dexue 3 at the three stages were between 153.53-208.26, 574.10-597.50 and 647.40-1 090.73 ng/g respectively. The total TSNA accumulations of Shiyan 1 at the three stages were between 305.63-526.81, 1 700.45-2 494.93 and 1 529.60-2 373.37 ng/g respectively. The accumulations of each TSNA and total TSNAs in the leaves at the different stages differed slightly between the two cultivars, the accumulations were all less before maturity and more at air-curing and fermentation stages. The total TSNA accumulation ratio of Dexue 3 was 30.65%-42.73% at air-curing stage and 46.29%-58.23% at fermentation stage and that of Shiyan 1 was 45.26%-48.22% and 40.71%-45.87% respectively. With the proceeding of air-curing and fermentation processes, the total TSNA contents in the leaves increased gradually. Therefore, air-curing and fermentation are the important stages for TSNA accumulation and the key stages for controlling their accumulation.