Near-Infrared Spectrometer for a Head-Feeding Combine for Measuring Rice Protein Content

Japan Agricultural Research Quarterly
ISSN 00213551
NII recode ID (NCID) AA0068709X
Full text
45-01-09.pdf546.12 KB

We have developed a near-infrared (NIR) spectrometer mountable on a head-feeding combine for measuring rice protein in real time while harvesting. The developed sensor employs reflectance optics instead of the more usual transmittance optics because (1) it operates under severe vibration and dust conditions; (2) it performs measurements in high moisture contents, low fluidity of rough rice; and (3) because of low light transmittance due to absorption by husks. The light source was a tungsten halogen lamp, with a diffusion cylinder installed so that uniform light would illuminate the sample. An Si-CCD measured the spectrum from 740 nm to 1140 nm with a post-dispersive grating. We made a calibration curve of brown rice protein from a spectrum of rough rice examined in a laboratory. The calibration curve accuracy was r= 0.87 and SECV (Standard Error of Cross-Validation) =0.47%. In the adopted measurement method, the sensor loaded the rough rice into a wide sample chamber by gravity and analyzed the loaded grain at the bottom using a reflected signal. The developed sensor was able to measure the protein content of brown rice from spectra of rough rice taken under severe conditions, e.g., a high-vibration, high-dust harvesting environment. In addition to the protein content, the rice weight and moisture content could be displayed on the monitoring terminal in real time. The accuracy of the protein content measurements in these field examinations was r=0.65 and SEP (Standard Error of Prediction) =0.22%. The SEP was far better than the SECV of the calibration, but the protein content fell in a narrow range in the field examination. Thus, we concluded that the actual accuracy was the same as the calibration.

Date of issued
Creator HIDAKA Yasuyuki KURIHARA Eiji HAYASHI Kazunobu NODA Takahiro NISHIMURA Yoh SUGIYAMA Takao MURAMATSU Kengo SASHIDA Kunio
Subject

yield-monitoring combine

precision agriculture

Publisher Japan International Research Center for Agricultural Sciences
Available Online
NII resource type vocabulary Journal Article
Volume 45
Issue 1
spage 63
epage 68
DOI 10.6090/jarq.45.63
Rights Japan International Research Center for Agricultural Sciences
Language eng

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