【摘要】 对白肋烟KY907在22℃和70%相对湿度下晾制表明,晾制后2～6周的叶肉和4～6周的主脉水分均迅速下降,晾制后1～4周电导率迅速提高,晾制后5天硝酸还原酶活性下降至0,体外硝酸还原酶活性很低,晾制3周后增加,这可能与微生物的作用有关。亚硝酸盐的变化与体外硝酸还原酶活性相似,硝酸盐在晾制中没有变化。成熟和晾制初期,烟草生物碱呈增加趋势。晾制后3周,主脉和叶肉中的4(N甲基亚硝氨)1(3吡啶)1丁酮(NNK)、N亚硝基去甲基烟碱(NNN)都为0,晾制后1周,主脉和叶肉亚硝胺和N亚硝基新烟草碱(NAT)均为0,其后逐渐增加。在全晾制过程中,主脉亚硝胺均高于叶肉。更多还原

【Abstract】 Burley tobacco (Nicotiana rustica) cv. Ky 907 was air cured at 22℃ and 70% RH and the changes of nitrosamines and their precursors in the lamina and midrib were observed. Moisture decreased rapidly in the 2～6th and 4～6th weeks, respectively, after air curing in the lamina and midrib. Electrical conductivity increased rapidly in the first 4 weeks of air curing. In vivo nitrate reductase activity (NRA) decreased to zero after 5 days of air curing, while in vitro NRA was initially low and increased after 3 weeks of air curing, which microbial NRA may have been responsible for. Changes in vitrite appeared to be similar to those in NRA in vitro. Nitrate did not change during air curing. Alkaloids increased during maturation and early stage of air curing. In both the lamina and the midrib, NNK and NNN were zero in the first 3 weeks of air curing and TSNA and NAT were zero in the first week of air curing before a rise in their contents occurred. TSNA was higher in the lamina than in the midrib.更多还原