Analysis on Chemical Composition of Pangola and Oat Hay by Hand-held Near-infrared Spectrometer

• Main Authors: Guo,Jhen-Jia, 郭振嘉
• Other Authors: Hsieh, Ching-Lu
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/j86bq9

碩士 === 國立屏東科技大學 === 生物機電工程系所 === 106 === Hay quality is an important factor that affects yield and quality of animal products. It also influences its market price. Therefore, it is crucial to have quantitative value on hay quality. Conventionally hay quality is judged manually by its appearance, smell, and chemical composition that needs tedious laboratory analysis. Spectroscopy in near infrared are techniques that have been broadly studied in agricultural field. Spectroscopy contain many advantages, such as, simple preparation for samples, non-destructive on samples, and quick detection. This study used near-infrared spectroscopy to calibrate a chemical composition for Pangola and Oat hay. Seventy Pangola and Eighty Oat hay for NIR analysis. The all Pangola hay samples were randomly collected from Kenting, a southern town in Taiwan. They were sampled by a motor driven drill cutter which made the length of hay straw and leaves in between 1~3 cm. Each sample was scanned by a monochrometer (microPHAZER) to record its reflective spectrum at 1600~2400 nm. Among these sample data, 2/3 of them were used as calibration set while the rest were used as test set. For spectroscopy to predict composition, PLSR (Partial least square regression) and MLR (Multiple linear regression) models were tested to predict CP (Crude protein), NDF (Neutral detergent fiber) and ADF (Acid detergent fiber). At Pangola hay of cut type, results showed the best model had R2 (coefficient of determination) on prediction and measurement on test set of 0.79, 0.50 and 0.52 for CP, NDF and ADF respectively and with RMSEP (root mean squared error of prediction) value of 0.97, 1.63, and 2.20. At Pangola hay of powder type, results showed the best model had R2 on test set of 0.95, 0.77 and 0.80 for CP, NDF and ADF respectively and with RMSEP value of 0.48, 1.14, and 1.58. The oat hay of cut type that had R2 on test set of 0.48, 0.31, and 0.46 for CP, NDF and ADF respectively and with RMSEP value of 1.94, 3.26, and 2.54. At oat hay of powder type that had R2 on test set of 0.94, 0.68, and 0.68 for CP, NDF and ADF respectively and with RMSEP value of 0.58, 1.21, and 1.77.