利用單管柱高效能分子篩層析區分稻米品種之理化特性

Classification of Physicochemical Properties of Rice Varieties by HPSEC with Single Column

吳及仕(Chi-Shih Wu) ； 張嘉宏(Chia-Hung Chang) ； 黃耀主(Yao-Chu Huang) ； 鄭統隆(Toong-Long Jeng) ； 郭孟怡(Meng-I Kuo)

《輔仁民生學誌》 19卷1期 (2013/06) Pp. 1-18

摘要

傳統稻米分類主要以視直鏈澱粉含量為主，其優點為實驗方便快速，但以光譜呈色法分類，可能受到支鏈澱粉與碘分子相結合形成複合物而影響準確度。利用分子篩層析法，以純化之澱粉做樣本，可估算更準確之數值。因此本試驗目的為利用單管柱高效能分子篩層析（HPSEC）測量米澱粉之直鏈澱粉含量以區分稻米品種的理化特性。結果顯示，HPSEC分析圖譜之波峰可分三個區塊，分別為高分子量支鏈澱粉區塊（F3）、低分子量支鏈澱粉區塊（F2）與直鏈澱粉區塊（F3）。進一步以F3分布比例區分稻米品種為高比例直鏈澱粉（High level amylose，HLA）、中比例直鏈澱粉（Medium level amylose，MLA）與糯性。此分類可將米澱粉之成糊特性、膨潤力與溶解度等理化特性可作更詳細區分，尤其F3與尖峰黏度（R^2=0.8137）及回升黏度（R^2=0.8598）呈現高度負相關，甚至優於傳統以視直鏈澱粉之分類法。然而米穀粉之成糊特性與米澱粉成糊特性並無直接之關係，但受到粗蛋白質含量影響。因此，本試驗利用HPSEC能更詳細區分稻米品種之理化特性，而米穀粉的理化特性除了與直鏈澱粉有直接的關係外，粗蛋白質含量也具有相當之影響力。

關鍵字

水稻 ； 高效能分子篩層析 ； 直鏈澱粉 ； 理化特性

並列摘要

The typical classification of rice variety is based on apparent amylose content. The advantages of this method are easy and fast. However, the accuracy of this colorimetry method using spectrometer might be affected by the formation of amylopectin-iodine complex. Size-exclusion chromatography for the analysis of amylose content in pure starch is more promising. Therefore, the objective of this research is to classify the physicochemical properties of rice varieties using the amylose content measured by high pressure size exclusion chromatography (HPSEC) with single column. Results show that the HPSEC spectrum of rice starch was divided into three areas, high molecular amylopection (F1), low molecular amylopectin (F2) and amylose (F3). The proportion of F3 was further used to classify the rice variety into high level amylose (HLA), medium level amylose (MLA) and waxy. Following this method, the pasting properties, swelling power and solubility of rice starch from different varieties could be clearly classified. F3 highly correlated with the peak viscosity (R^2=0.8137) and setback (R^2=0.8598). Thus, the classification proposed by this research was better than traditional method by apparent amylose content. However, the pasting properties of the rice flour did not correlate well with that of rice starch and was affected by protein content. In conclusion, the physicochemical properties of rice varieties could be classified by using HPSEC with single column. The physicochemical properties of rice flour were not only affected by amylase content but also protein content.

並列關鍵字

rice ； HPSEC ； amylase ； physicochemical properties