稻米品質理化特性與米飯食用品質間關係之探討

Abstract

利用117個不同直鏈澱粉含量稻品種進行稻米品理化特性化之研究，並探討其與米飯食用品質間的關係。由多比結果得知欲判別不同直鏈澱粉含量品種類群之差異時，米質理化特性中僅有米飯均性一項最佳判別性狀；若就不同食味等級類群而言，以米飯均衡性、直鏈澱粉含量、非水溶直鏈澱粉含量、最大吸收波長及總醣含量等五為最佳之判別性狀。經由米質化特性表現之相關分析與因素分析結果，顯示糯性，低直鏈澱粉含量，中等直鏈澱粉含品種及高直鏈澱粉含量品類群間之現不完全相同，其中以合所有品種性狀間之相關顯著性最多。當米飯食味總評設Y時，以米質理化性對米飯食味總評進行逐步迥歸分析，得到一較佳的歸式Y=3.89362 (Ba) - 0.0138 (AC) – 0.01503 (SA) + 0.16846 (TS) – 0.04285 (Pro) -0.21202，其中Ba為米飯均衡性、AC為直鏈澱粉含量、SA為水溶性直鏈澱粉含量、TS為總糖含量、Pro為蛋白質含量；其較佳之主成份迴歸方程式為Y=0.78459 (F1) + 0.25613 (F2) – 0.21131 (F3) – 0.10664 (F5)，決定係數依序為0.755與0.737。 The changes in the physicochemical property f rice quality were studied for 117 rice varieties with different amylase contents and further to explore the relationship between physicochemical properly and eating quality of cooked rice. To differentiate significantly among four varieties groups of amylose content, just balance of cooked rice could be used. To differentiate significantly among three varieties groups of palatability grades, the following five characters could be used: balance of cooked rice, amylose content, insoluble amylase content, peak wavelength of absorption and total sugar content. The performance of correlation and factor analysis was found to be quite different among waxy, low-amylase, intermediate-amylose, high-amylose groups of rice varieties. Significance of correlation was the most for group of combined all the tested varieties. The estimated regression model for overall sensory evaluation of cooked rice based on physicochemical properties, the best regression equation was 3.89362 (Ba) - 0.01138 (AC) - 0.01503 (SA) + 0.16846 (TS) - 0.04285 (Pro) - 0.21202 ' where Ba: balance of cooked rice, AC: amylase content, SA: soluble amylose content, TS: total sugar content, Pro: protein content. The principal component regression equation was - 0.39849(F2) - 0.23278(F3) - 0.33602(F4). The coefficients of determination of regression equations were 0.755 and 0.737, respectively.