Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: 1/19/2011
Publication Date: 4/21/2011
Citation: Liu, Y., Gamble, G.R., Thibodeaux, D.P. 2011. Direct and rapid determination of cotton maturity by FT-Mid-IR technique. National Cotton Council Beltwide Cotton Conference. Available: http://ncc.confex.com/ncc/2011/webprogram/Paper11593.html. Interpretive Summary: The impact of cotton maturity on cotton fiber quality and finished textile products has been a major concern for cotton growers and textile manufacturers over many years. Immature fibers, which have little cell wall thickening relative to fiber perimeter, were found to be prone to entanglement formation during the mechanical processing and also to alter the desired color appearance in dyed yarn and fabric. AMS, testing companies, and foreign organizations have developed a number of microscopic and instrumental devices for measuring the cotton fiber maturity directly and indirectly. In general, these methods require a large number of samples (> 0.5 g), utilize air-flow measurements and a theoretical approach, and depend on fiber maturity reference (that a procedure is very subjective and is difficult to access the degree of maturity) for the accuracy. This study demonstrates that FT-mid-IR technique could be an alternative approach in the classification of mature fibers from immature ones, and also in the determination fiber maturity. The obtained result provides agricultural engineers and cotton fiber researchers a new sight in applying FT-mid-IR spectroscopy for rapid, routine, and direct measurement of cotton fiber maturity.
Technical Abstract: FT-mid-IR (FT-MIR) spectra of seed and lint cottons were collected to explore the potential for the discrimination of immature cottons from mature ones and also for the determination of actual cotton maturity. Spectral features of immature and mature cottons revealed large differences in the 1200-900 cm-1 region, and such spectral distinctions formed the basis on which to develop simple three-band ratio algorithm for classification analysis. Next, an additional formula was created to assess the degree of cotton fiber maturity by converting the three-band ratios into an appropriate FT-MIR maturity (MIR) index. Furthermore, the MIR index was compared with parameters derived from traditional image analysis and AFIS module. Results indicated strong correlations (R2 > 0.89) between MIR and MAFIS and between MIR and MIA among either International Cotton Calibration (ICC) standards or selected cotton maturity references. On the other hand, low correlations between the pairs were observed among regular cotton fibers, which likely resulted from the heterogeneous distribution of structural, physical, and chemical characteristics in cotton fibers and subsequent different sampling specimens for individual and independent measurement.