臺灣產澱粉理化性質之研究 第四報 數種澱粉之Amylopectin劃分之分離及其理化性質

Studies on the Physical and Chemical Properties of the Starches Produced in Taiwan IV. Isolation and Characterization of the Amylopectin Components of Some Starches

謝伯東(Po-Tung Hsieh) ； 蔡錫舜(Shi-Shun Tsai) ； 吳家鐘(Chia-Chung Wu)

《化學》 61年4期 (1972/12) Pp. 133-140

https://doi.org/10.6623/chem.1972018

摘要

依Schoch氏之正丁醇－異戊醇選擇沉澱法自臺灣產之糯米、蓬萊米、在來米、小麥、甘藷及樹薯等六種澱粉分離出其amylopectin劃分，並就此等劃分測定其若干理化性質，藉以探討各種amylopectin之若干微細構造以期獲得各種澱粉利用上之基礎資料。所得之結果可綜合如下：(1)除甘藷及在來米澱粉amylopectin之碘親和力分別爲0.4及0.3%外，糯米、蓬萊米、小麥及樹薯等之amylopectin碘親和力均近於零。將各種amylopectin-碘複合體在可視光範圍內測定其最大吸光波長之結果，顯示甘藷及在來米之amylopectin有長直鎖部份之存在。(2)分離所得amylopectin之單位鎖平均重合度以糯米爲最小而甘藷爲最大，其它四種amylopectin則介於兩者之間(21~28glucose units)。其大小依甘藷、在來米、樹薯、蓬萊米、小麥、糯米之次序減小。(3)各種amylopectin之β-amylolysis limit 除樹薯為61%外，其他各種amylopectin分佈於55~58%之間。(4)各種amylopectin水溶液之安定性均相當大，於低溫(2~4°C)下放置30日並無老化現象發生。

並列摘要

By means of selective precipitation procedures with n-butanol and iso-amyl alcohol, six kinds of starches produced in Taiwan were fractionated into their amylose and amylopectin components. The isolated amylopectin components were characterized, and their physico-chemical properties were compared. The results obtained were summarized as follows: (1) The blue values for the amylopectins ranged from 0.08 to 0.14. (2) The iodine affinities of the amylopectins isolated from sweet potato and native rice were 0.4% and 0.3%, respectively, while those of the amylopectins from glutinous rice, Penlai rice, wheat, and cassava starches were all approximately zero. (3) The values for the average length of unit chain of the amylopectins were seen to vary from 21 to 28 glucose units. The order of the magnitude of the average length of unit chain in the six amylopectins decreased as follows: sweet potato＞ native rice＞ cassava＞ Penlai rice＞wheat＞ glutinous rice. (4) The values for the β- amylolysis limit for the amylopectins, except that from cassava starch, for which the value was 61%, vaired between 55% and 58%. (5) By measurment of intrinsic viscosity, it was considered that the molecular size of each of the amylopectins from glutinous rice, sweet potato, Penlai rice, and cassava starches was nearly the same and was larger than those from wheat and native rice starches. (6) The aqueous solutions of the amylopectins were considered to be stable, because there was no retrogradation observed, when 1% aqueous solutions of the amylopeetins had been stored at the temperature 2~4°C for 30 days.