Properties of Lotus-seed Starch

概要

論文の詳細を見る
Starch in embryo of lotus seed (Nelumbo nucifera GAERTN.) was prepared by wet milling with dilute alkali, and its chemical and physical properties were investigated in comparison with starches of lotus rhizome (lotus root), maize (corn) and potato. The results were as follows. 1. The starch granules of lotus seed measured by scanning electron microscopy (SEM) were small and oval in shape with an average size of 13 sum. These were quite different compared with very large ellipsoidal shape (30×60μm) of lotus-root starch. 2. By X-ray diffractometry, the lotus-seed starch showed A-type patterns. 3. The digestibility of the lotus-seed starch granules by fungal glucoamylase (Nagase) was 100% in 24 hr reaction while that of the lotus root was about 42%. 4. The initiation temperatures of the lotus-seed and -root starches were 79 and 65°C by amylography, 67.5 and 65°C by photopastegraphy, and 69.9 and 56.7°C by differential scanning calorimetry, respectively. The maximum viscosity of the lotus-seed starch measured by Brabender's amylography was 610 B.U., higher than those of the lotus-root starches. 5. The apparent amylose content of the lotus-seed starch determined by the amperometric iodinetitimetry and gel filtration after isoamylase-debranching was 27.7 and 29.9%, respectively, indicating higher amylose contents than the lotus-root starch, 21.7 and 18.5%, respectively.
日本応用糖質科学会の論文