Study on the Relationship between Chromaticity Signal Values and Plastid Pigments in Different Sections of Tobacco Leaves during Curing Process

SHAN Jiaye; WANG Qiuling; LI Chunguang; LI Quansheng; ZOU Shenghao; SUN Mi; LUO Dongsheng; XI Feihu; JING Yanqiu

doi:10.15933/j.cnki.1004-3268.2025.02.019

Abstract：In order to achieve online monitoring of plastid pigments and colors in different sections of tobacco leaves during the baking process,and provide reference for the processing of different sections of tobacco leaves and the realization of intelligent baking,technologies such as chromaticity signal monitoring equipment,acetone spectrophotometer colorimetric method,and colorimeter were used to measure the chromaticity signal values,pigment content,and color parameters of different sections of tobacco leaves at key temperature points during the baking process,and analyze their changes.Correlation analysis and regression analysis methods were used to analyze the correlation between chromaticity signal values,pigments,and color parameters,and regression equations between chromaticity signal values and pigments were constructed and verified.The results showed that there were significant differences in the content of chlorophyll and carotenoids in different sections of fresh tobacco leaves during the baking process,manifested as leaf base>leaf middle>leaf tip.The correlation analysis results showed that the brightness value(L*),redness value(a*),and yellowness value(b*)of different sections of tobacco were significantly negatively correlated with the content of chlorophyll a,chlorophyll b,chlorophyll,and carotenoids;The chromaticity signal values in different sections were significantly positively correlated with brightness value(L*),redness value(a*),and yellowness value(b*),and significantly negatively correlated with chlorophyll a,chlorophyll b,chlorophyll,and carotenoid content.The regression analysis results indicated that the chromaticity signal values of tobacco leaves in different sections had a high degree of fit with chlorophyll a,chlorophyll b,chlorophyll,and carotenoid content;The regression equation validation results showed that the relative errors of chlorophyll a,chlorophyll b,chlorophyll,and carotenoid content in the leaf base were 8.19%,9.13%,8.42%,and 13.58%,respectively.The relative errors of chlorophyll a,chlorophyll b,chlorophyll,and carotenoid content in the leaf middle were 11.39%,6.63%,10.42%,and 7.63%,respectively.The relative errors of chlorophyll a,chlorophyll b,chlorophyll,and carotenoid content in the leaf tip were 11.47%,10.79%,10.21%,and 11.58%,respectively.In summary,the chromaticity signal monitoring equipment has small experimental errors,high degree of automation,and high accuracy,which can achieve rapid and accurate monitoring of pigment in different sections of tobacco during the baking process.