title: Early detection of germinated wheat grains using terahertz image and chemometrics.
abstract: In this paper, we propose a feasible tool that uses a terahertz (THz) imaging system for identifying wheat grains at different stages of germination. The THz spectra of the main changed components of wheat grains, maltose and starch, which were obtained by THz time spectroscopy, were distinctly different. Used for original data compression and feature extraction, principal component analysis (PCA) revealed the changes that occurred in the inner chemical structure during germination. Two thresholds, one indicating the start of the release of α-amylase and the second when it reaches the steady state, were obtained through the first five score images. Thus, the first five PCs were input for the partial least-squares regression (PLSR), least-squares support vector machine (LS-SVM), and back-propagation neural network (BPNN) models, which were used to classify seven different germination times between 0 and 48 h, with a prediction accuracy of 92.85%, 93.57%, and 90.71%, respectively. The experimental results indicated that the combination of THz imaging technology and chemometrics could be a new effective way to discriminate wheat grains at the early germination stage of approximately 6 h.
authors.affiliation: State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100080, China.|University of Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Yuying
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Grain Information Processing &Control, Ministry of Education, Henan University of Technology, Zhengzhou 450001, China.
authors.forename: Hongyi
authors.initials: H
authors.lastname: Ge
authors.affiliation: Key Laboratory of Grain Information Processing &Control, Ministry of Education, Henan University of Technology, Zhengzhou 450001, China.
authors.forename: Feiyu
authors.initials: F
authors.lastname: Lian
authors.affiliation: Key Laboratory of Grain Information Processing &Control, Ministry of Education, Henan University of Technology, Zhengzhou 450001, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Shanhong
authors.initials: S
authors.lastname: Xia
mesh_terms: D018525:Germination; D016018:Least-Squares Analysis; D016571:Neural Networks, Computer; D025341:Principal Component Analysis; D060388:Support Vector Machine; D055068:Terahertz Spectroscopy / Q000379:methods; D013997:Time Factors; D014908:Triticum / Q000254:growth & development*