Effects of Loading Position and Maturity on the Quality of Cured Tobacco Leaves

To improve the curing quality of upper tobacco leaves, this study used Yunyan 87 as the test material. Based on visual maturity, the leaves were divided into three grades: relatively immature（M1）, normally mature（M2）, and relatively overmature（M3）. Curing experiments were carried out by combining different loading positions in a bulk curing barn, and the quality and economic benefits of the cured leaves were comprehensively evaluated. The results showed that the M2 treatment exhibited the best overall quality. Although the loading position had a limited effect on leaf quality, when placed in the lower layer, the chemical components were more harmonious, and it achieved the highest total sensory evaluation score and economic return; upper-layer loading improved its appearance quality. For the M1 treatment, upper-layer loading resulted in the best overall quality, significantly increasing the potassium-to-chloride ratio and sensory evaluation score. For the M3 treatment, lower-layer loading showed the best comprehensive quality, significantly outperforming the middle and upper layers in total sensory evaluation score, appearance quality（color and chroma）, and average price. This study provides a reference scheme for the precise curing of upper tobacco leaves.