不同变黄程度下烤烟淀粉酶活性的变化及对其相关化学成分的影响

研究了在三段式烘烤工艺配套技术条件下不同变黄程度烤烟烟叶内淀粉酶的活性及与其相关化学成分的变化规律.结果表明,在不同变黄处理下,淀粉酶呈“升高—降低—升高”的规律,其中,下部叶八成黄、中部叶十成黄、上部叶十成黄的淀粉酶活性整体上最高.随着烘烤时间的延长,烟叶内淀粉、还原糖含量升高,其中,下部叶的八成黄、中部叶的九成黄、上部叶的十成黄表现最为明显.淀粉与还原糖含量之间均呈显著负相关.烟叶烘烤后,下部叶在七至八成黄转火定色条件下,化学成分含量适宜,各成分间比例协调;中部叶在八至九成黄转火定色条件下,化学成分含量适宜,各成分间比例协调;上部叶在十成黄转火定色条件下,化学成分含量适宜,各成分间比例协调.

Change of amylase activity and its influence on chemical components in flue-cured tobacco under different yellowing condition

Amylase activity and changing rules of chemical components in differently yellowed leaves of flue-cured tobacco were studied under the three-stage-process roasted condition. The results showed that amylase activities in differently yellowed leaves revealed a rule of in- crease-reductionrincrease; among these, amylase activities in lower leaves yellowed by 80%, middle and upper leaves completely yellowed were the highest overall. With the time of roast- ing,the contents of starch and reducing sugars in tobacco leaves increased, and obvious in- creases occurred in lower leaves yellowed by 80% ,middle leaves yellowed by 90% and upper leaves completely yellowed. Contents of starch and reducing sugars were negatively and sig- nificantly related. After leaves of flue-cured tobacco were roasted, appropriate contents and harmonious combinations of chemical components were obtained in lower leaves with color fixed under 70% to 80% yellowing,middle leaves with color fixed under 80%~90% yello- wing and upper leaves with color fixed under 100% yellowing.