张书伟 过伟民 陈祥 张子颖 徐文韬 叶校坤 周汉平 常乃杰

摘  要：为明确烟叶柔韧性与内在品质的关系，优化烤烟外观品质评价指标体系，选择我国6个生态二级区上部和中部不同质量梯度烟叶样品，采用相关分析和随机森林回归分析，研究了烟叶柔韧性与主要化学成分和感官品质指标的关系。结果表明，烟叶柔韧性区域差异明显，渝东南烟叶柔韧性好，豫西、湘南烟叶次之，而滇东和豫中地区烟叶总体一般。烟叶柔韧性分值与还原糖、总糖含量，糖碱比值和两糖比值呈显著或极显著正相关。烟叶柔韧性分值与香气质、香气量、杂气、刺激性、干燥感、回甜感等感官指标呈极显著正相关。随机森林回归分析发现，部分地区柔韧性对还原糖含量、香气质和感官综合品质分值变异的贡献率大于其他外观指标。烟叶柔韧性能够较好地表征内在品质，可用于优化烤烟外观品质评价指标体系。

关键词：烤烟;柔韧性;化学成分;感官品质;相关分析;随机森林

Abstract： To clarify the relationship between flue-tobacco toughness and internal quality， and to optimize the evaluation index system of flue-cured tobacco appearance quality， we collected upper and middle parts flue-cured tobacco leaf samples from six ecological secondary regions in China. Correlation and Random forest regression analysis were used to study the relationship between tobacco leaf toughness and main chemical components and sensory quality indexes. The main results were as follow： Obvious regional differences in leaf flexibility were observed. The flue-tobacco toughness score of southeastern Chongqing was good， followed by western Henan and southern Hunan， while eastern Yunnan and central Henan was generally average; Toughness was significantly or extremely significantly positively correlated with reducing sugar （RS） and total sugar content （TS）， the ratio of reducing sugar and total sugar （RS/TS） and the ratio of reducing sugar and nicotine （RS/Nic）; The toughness score of tobacco leaves was significantly positively correlated with aroma quality， aroma quantity， odor， irritation， dryness and return sweetness and other sensory indexes; Random forest regression analysis showed that the contribution rate of toughness to the variation of RS， aroma quality and total sensory score was higher than that of other appearance indexes. Therefore， toughness can better represent the intrinsic quality of flue-cured tobacco leaves and play an important role in simplifying the assessment indicators of flue-cured tobacco leaf quality.

Keywords： flue-cured tobacco; toughness; chemical components; sensory quality; correlation analysis

烤煙外观特征是烟叶生产、收购、调拨环节评价烟叶品质的主要依据。国家标准[1]规定的烤烟外观分组和分级因素包括颜色、成熟度、叶片结构、身份、油分、色度、长度和残伤等。以上述外观因素为依据，中国烟草种植区划[2]建立了烤烟外观品质量化评价体系，成为目前我国烟叶外观品质量化评价的主要方法。除了国标[1]规定的外观品质因素外，探索更多的外观评价延伸指标，更为全面地通过外观评价预测烟叶内在质量的研究也在不断深入。……