Predicting extractives and lignin contents in Eucalyptus globulus using near infrared reflectance analysis

Lignin and extractive content are important determinants of the pulping quality of wood. Determination of extractive and lignin content using traditional chemical methods is a costly and time-consuming process. Near infrared reflectance (NIR) analysis offers a low cost alternative for prediction of wood quality. Calibrations were developed for the prediction of extractives content, acid-soluble lignin, Klason lignin, and total lignin contents. Each calibration had standard errors of less than 0.6%. Laboratory measurements for a separate set of samples were highly correlated with predicted values (R-2 of 0.89 for extractives content, 0.83 for acid-soluble lignin content, 0.97 for Mason lignin content, and 0.99 for total lignin content). It was concluded that NIR analysis is a reliable predictor of extractive and lignin content in Eucalyptus globulus.