基于“翠碧1号”品种烟叶典型力学特性的打叶复烤加工技术及应用

Threshing and redrying technology based on typical mechanical characteristics of tobacco leaves of cv.“CB-1”

为解决“翠碧1号”品种烟叶在打叶复烤过程中存在大片率过高、复烤后片烟颜色转深明显等问题,分析了“翠碧1号”烟叶力学特性,确定了其典型力学特征,并根据其典型力学特征研究制定了打叶复烤加工技术。研究结果表明:①与其他品种烟叶相比,“翠碧1号”烟叶具有油分较充足(黏附力较大),韧性较强(拉力和穿透力较大)以及结构较为疏松(剪切力较小)的典型力学特性。②“翠碧1号”烟叶打叶复烤二润出口含水率不宜高于17.0%,复烤单区最高热风温度不宜超过75℃。③基于“翠碧1号”烟叶典型物理特性,建立了以“低含水率打叶、低强度复烤”为核心的“翠碧1号”品种烟叶打叶复烤加工技术:二次热风润叶方式由“水+蒸汽”调整为“蒸汽”,二润出口含水率由18.5%调整为17.0%,片烟复烤段单区最高热风温度由75℃降至70℃,片烟复烤段各干燥区热风温度总和降低35℃。④在打叶经济效益基本稳定的基础上,“翠碧1号”烟叶打后片烟结构均匀性得到优化:上部和中部烟叶的大片率分别降低1.9百分点和2.4百分点;中片率分别提高1.3百分点和3.3百分点;碎片率分别降低0.2百分点和0.1百分点;出片率分别提高0.39百分点和0.04百分点;成品综合得率分别提高0.21百分点和0.58百分点。

In order to produce higher percentage of large-sized strips and avoid color darkening following threshing and redrying,typical mechanical characteristics of“CB-1”tobacco leaves were determined and used to refine the threshing and redrying parameters.The results showed that:1)Comparing with other tobacco varieties,“CB-1”leaves had a sufficient oil content(higher viscidity),a higher tensile force and penetrability,and looser structure(lower shearing force).2)The moisture content in“CB-1”leaves out of the second stage ordering cylinder should not be higher than 17.0%and the maximum hot air temperature in the single zone of tobacco redrying section should not be higher than 75℃.3)Basing on the leaf physical properties,the threshing and redrying parameters for“CB-1”leaves were developed,namely a low moisture content threshing and low intensity redrying as the key objective.The second stage hot air ordering mode was changed from“water+steam”into“steam only”,the moisture content in leaves out of second stage ordering cylinder was decreased from 18.5%to 17.0%,and the maximum hot air temperature in the single zone of tobacco redrying section was lowered from 75 to 70℃.The total temperature of the hot air in strip redrying section was reduced by 35℃.4)On the basis of stable economic benefit of threshing,the uniformity of strip structure of threshed“CB-1”leaves was optimized.The percentage of large-sized strips for upper and middle leaves decreased by 1.9 and 2.4 percentage points,the percentage of medium-sized strips increased by 1.3 and 3.3 percentage points,the percentage of small-sized strips reduced by 0.2 and 0.1 percentage points,the strip yield raised by 0.39 and 0.04 percentage points,and the comprehensive product yield increased by 0.21 and 0.58 percentage points,respectively.