Appearance Characteristics of Honey-Sweetness and Burnt Flavor Type Flue-cured Tobacco of Yimeng Hilly Ecological Areas and Their Relationships with Tobacco Leaf Quality

To clarify the appearance identification characteristics of distinctive tobacco leaves of the Yimeng hilly ecological area with honey sweetness and burnt flavor type,the appearance regional characteristics and appearance quality characteristics of C2F tobacco leaf samples from 3 main planting areas (Weifang,Rizhao and Linyi in Shandong) were evaluated,compared with other flavor areas in China,and their relationships with routine chemical components and sensory quality were analyzed.The results showed that the appearance characteristics of tobacco leaves in the area were as follows:white to slightly grey background color,mainly moderate thickness,weak to moderate wax texture,relatively brittle-hard leaves,minor to moderate leaf color difference between front and back, mainly minor leaf body difference between tip and base,bright to slightly dark luster,relatively smooth to slightly rough tissue,orange color,mainly ripe,firm to open structure,mainly moderate body,oily-oil,and moderate color intensity.Compared with other flavor areas,background color,flexibility,leaf surface tissue and luster were the main identification indexes of tobacco leaves in the area. Correlation and gradual regression analyses showed that the thicker the thickness,the lower the values of potassium content,total nitrogen/nicotine,potassium/chlorine,and sugar/nicotine,the higher the contents of nicotine and chlorine,the more obvious the honeysweetness,green scents and honey-sweetness and burnt flavor type,the more overflow with smoothness the aroma,the higher the concentration,but the weaker the woody,burnt-sweetness and burnt scents;the rougher the leaf surface tissue,the better the aroma quality,the more abundant the aroma and the more delicate and softer the smoke.In conclusion,white to slightly grey background color,relatively brittle-hard leaves,relatively smooth to slightly rough tissue,and bright to slightly dark luster were the main appearance identification characteristics of tobacco leaves in the area.Thickness was the key index to influence the chemical composition and sensory style of tobacco leaves in the area.Leaf surface tissue was the key index to influence the sensory quality of tobacco leaves.