Based On The Application Of Near Infrared Spectroscopy In The Determination Of Maturity Of Tobacco Leaves And Studied The Quality Of Flue-cured Tobacco Leaves

Maturity directly affects the quality of flue-cured tobacco leaves,tobacco leaf maturity in China is basically judged by tobacco farmers,the accuracy is not high.Therefore,it is urgent to find a scientific,fast,and practical method for the detection of tobacco leaf maturity.Near infrared spectroscopy(NIR)is a non-destructive and rapid detection method,which has been widely used in tobacco industry.In this study,the qualitative analysis and e-Research of the maturity of K326 tobacco leaves were carried out by near infrared spectroscopy.The results are as follows:(1)the environmental factors have a great influence on the spectrum of the near infrared spectrum in the field.Under different conditions of illumination,temperature and so on,the near infrared spectra were different.In order to enhance the accuracy and applicability of the model,it is necessary to adjust the illumination and temperature.(2)found on the degree of qualitative analysis of mature tobacco leaves: compared with principal component analysis(PCA)and K nearest neighbor algorithm(KNN),support vector machine(SVM)method,the Random forest(RF)method can effectively classify near infrared spectral information of K326 Tobacco Maturity classification.The RF method of prediction accuracy is superior to the other methods,the prediction of the upper leaves and lower leaves of higher accuracy,the training set accuracy rate reached above 87.5%,prediction accuracy is above 90%,and compared with other methods of relative stability.(3)the correlation between SPAD value and maturity of tobacco leaf was stronger,and the maturity of tobacco leaf could be reflected by SPAD value.PLS method was used to establish the quantitative prediction model of tobacco leaf SPAD in order to realize the e-Research of tobacco leaf maturity.The results showed that the quantitative prediction model of tobacco leaf SPAD was ideal,with less error and higher accuracy.This shows that the near infrared spectroscopy can be used to e-Research the maturity of tobacco leaves.(4)In the analysis of the quality of flue cured tobacco leaves by means of near infrared spectrum model,the physical properties,appearance quality and chemical composition of the flue-cured tobacco leaves with different maturity were found to be different in the analysis of the quality of the flue-cured tobacco leaves under 5 different degrees of maturity.This shows that the established model is reliable and can analyze tobacco leaves in many ways so as to differentiate the maturity of tobacco leaves.(5)K326 on baking quality were detected,the results indicated that,upper leaves from leaves to grow to maturity,the tensile strength and the equilibrium moisture content increased,and reached the maximum value in tobacco leaf maturity,long to mature,the tensile strength and the equilibrium moisture content decreased.The percentage of M4 in the upper leaves and the middle leaves of M3 was lower,the filling value was higher,the thickness was moderate,and the usability was better.The color of M3 and M4 in the middle and upper tobacco leaves was orange,the leaf structure was loose,the identity was medium or slightly thick,the oil was more,the color was strong,and the appearance quality was better.The total sugar content of middle leaves was 24%-25%,the total sugar content of upper leaves was 27%-29%,and the content was high.In addition,nicotine content was also higher.The contents of total sugar,reducing sugar,nicotine and potassium were gradually increased,and the contents of total sugar and reducing sugar were decreased as long as the ripening period.Nitrogen decreased with the increasing of tobacco leaf maturity.