CORRELATION OF NIR DATA WITH COTTON QUALITY CHARACTERISTICS

A desire for improvement of the state of the art in cotton quality mea surements, and for application of such measurements to the ginning pro cess, has prompted investigation of near-infrared reflectance (NIR) as a means of measuring different cotton quality characteristics. Cotton samples from five different cotton sources covering a range of white color grades were ginned with three different lint-cleaner treatments. The lint samples then underwent a full set of High Volume Instrument quality tests at a cotton classing office. The samples were subsequent ly measured on an NIR spectrophotometer at 2-nm intervals from 1100 to 2500 nm. These 700 measurements were averaged into 14 bands of 100 nm in width. Ratios of the bands were calculated and statistical model s election procedures were used to establish optimal regression models s he quality characteristics with continuous values. Correlations of the models to the quality characteristics were also calculated Optimal mo dels showed the following R(2) values in relation to their correspondi ng cotton quality characteristics-0.88 for reflectance, 0.85 for yello wness, 0.60 for trash content, 0.96 for micronaire, 0.73 for strength, 0.79 for length, and 0.67 for length uniformity. The NIR ratios were also employed in discriminant analyses to establish models for classif cation of discrete attributes of the cotton samples. Classification ac curacies were 93% for cotton source, 91% for combined source and lint- cleaner treatment, 93% for color grade, and 70% for color-grade quadra nt.