作者：洪梅珠　郭寶錚　楊珮雅

　　 本試驗主要選用在台灣生產的稉稻、秈稻及糯稻為材料，以 Bran+Luebbe 公司製造之 InfraAlyzer 500 連續波長型的近紅外光分析儀 (Near infrared reflectance spectrophotometer, NIRS) 進行掃描，期建立白米粉末糊化溫度、破裂比值、回升比值、膠質比值及相對破裂比值等 5 個黏度特性之檢量線，作為水稻育種上進行選拔及稻米加工業者控制產品品質參考之用。結果發現利用複線性迴歸分析 (Multiple linear regression, MLR) 所建立的糊化溫度檢量線，其相關係數為 0.945 、 RPD ratio 值為 3.00 ，破裂比值檢量線之相關係數為 0.783 、 RPD ratio 值為 1.54 ，回升比值檢量線之相關係數為 0.801 、 RPD ratio 值為 1.74 ，膠質比值檢量線之相關係數為 0.956 、 RPD ratio 值為 3.12 ，相對破裂比值檢量線之相關係數為 0.961 、 RPD ratio 值為 3.68 。上述所製作的檢量線中，有糊化溫度、膠質比值及相對破裂比值的 RPD ratio 值大於 2.5 ，表可供育種上作初步篩選之用，但尚未達到可作為品質控制的程度。

關鍵字： 水稻、近紅外光分析儀、黏度特性。

　　By employing different rice varieties, including japonica, indica and waxy rice grown in Taiwan, a method was developed to determine pasting temperature, breakdown ratio, setback ratio, consistency ratio and relative breakdown ratio of ground milled rice by the near infrared reflectance spectrophotometer (NIRS, Bran+Luebbe Infra Alyzer 500). The results of multiple correlation coefficient and RPD values determined by multiple linear regression (MLR) modeling are shown in accordance: r=0.945 and RPD ratio=3.00 for pasting temperature; r=0.783 and RPD ratio=1.54 for breakdown ratio; r=0.901 and RPD ratio=1.74 for setback ratio; r=0.956 and RPD ratio=3.12 for consistency ratio; r=0.961 and RPD ratio=3.68 for relative breakdown ratio. Models for breakdown ratio and setback ratio predicted by MTRS were not sufficiently accurate (RPD ratio<2.5) to warrant replacement of the RVA procedure. However, the optimal calibration curve for pasting temperature, consistency ratio and relative breakdown ratio shows a higher multiple correlation coefficient (r>0.94) and RPD ratio (>2.5). Such accuracy is not sufficient for rice quality control during processing, but sufficient for initial screening of high quality rice varieties in breeding program.

Key words: rice, near infrared reflectance spectrophotometer, viscosity properties.