New Starches. IV. The Properties of the Starch from Typha latifolia

On the Relationship between Regain and Crystallinity of Starch

“…( A = accessibility of polymer, c = accessibility of crystalline portion, x = crystallinity). Mark assumed that effective adsorbed surface development of the crystalline portion was represented by an infinitely 184 reportedas0.19byKast [6]andasO.17 byHowsmon [16]. Kast reported that the crystallite was of cylindrical form for square prism by Mark and a halfof all glucose residues on the surface of the cylinder was effective for adsorption [6].…”

“…Mark assumed that effective adsorbed surface development of the crystalline portion was represented by an infinitely 184 reportedas0.19byKast [6]andasO.17 byHowsmon [16]. Kast reported that the crystallite was of cylindrical form for square prism by Mark and a halfof all glucose residues on the surface of the cylinder was effective for adsorption [6]. The author also calculated the accessibility of the crystalline portion of starch and cellulose depending on Kast's method as shown in Table 3.…”

“…It is supposed that the r-value may be 0.667. The value of regain of cellulose is calculated with the r-value of 0.667, the crystallinity of 0.70 [9] and the g-value of 0.18, the value of regain becomes 0.28 which is the same value of the fiber saturation point [21], and on this value of regain the accessibility of cellulose becomes 0.42 which is almost same value of 0.44 by Kast [6] and Howsrnon [16]. Assuming the r-value is 0.667, the crystallinity of starch is calculated on each o-value and the saturation moisture regain which are 0.49, 0.44 and 0.42 for potato, sweet potato and corn starch, respectively.…”

“…The size of unit cell of starch was already reported by Rundle [I 11,Kreger [12] and French [13], and that of cellulose was done by Meyer [14]. The dimensions ofcrystallite ofcellulose arereportedin therangeoflOOto2008,andabout 508, [6,15,161. The dimensions ofcrystallite of starch are also reported in the range of 120 to 130A and about 608, [17, 18, 191. Assuming the dimension of crystallite to be 130 8, for starch and 1008, for cellulose, the values of accessibility of crystalline portion of starch and cellulose are calculated by Mark's method as shown in Table 2.…”

Some Anomalies in Starch Chemistry Are They Due to Granule Structure ?

“…Figure 4 shows the Brabender amylogram for canary grass resembles that of high amylose starch. Brabender amylograms at 6 and 7% level on canary grass It also has other properties resembling high amylose starch namely, a low solubility, low swelling power and high pasting temperature. These properties are explained for high amylose starch by the extensive H-bonding due to large amount of amylose present.…”