Carbohydrate amylopectin

Salivary a-amylase is a protein that contributes to the enamel pellicle (Sect. 12.1.3). More importantly, it attaches bacteria, especially streptococci, to teeth surfaces. Thus, following a meal rich in carbohydrates, amylopectin, amylase, and glycogen are digested to maltose at the surface of many oral bacteria. The maltose is taken into the cytosol by a phosphoenolpyruvate transporter homologous to the fructose transporter of S. mutans. Within these bacteria, the maltose is digested to two molecules of glucose 6-phosphate and metabolized to lactic acid. Thus, twice as much acid is produced per mole maltose than per mole sucrose and it contributes to tooth demineralization even if less sucrose is consumed. 

Similar materials are available based on potato starch, eg, PaseUi SA2 which claims DE below 3 and has unique properties based on its amylose—amylopectin ratio pecuhar to potato starch. The product contains only 0.1% proteia and 0.06% fat which helps stabilize dried food mixes compounded with it. Another carbohydrate raw material is waxy-maize starch. Maltodextrias of differeat DE values of 6, 10, and 15, usiag waxy-maize starch, are available (Staley Co.). This product, called Stellar, is offered ia several physical forms such as agglomerates and hoUow spheres, and is prepared by acid modification (49). Maltodextrias based oa com starch are offered with DEs of 5, 10, 15, and 18 as powders or agglomerates (Grain Processing Corp.). 

In order to gain some information about the fundamentals of the hydrothermal carbonization process, the hydrothermal carbonization of different carbohydrates and carbohydrate products was examined [12, 13]. For instance, hydrothermal carbons synthesized from diverse biomass (glucose, xylose, maltose, sucrose, amylopectin, starch) and biomass derivatives (HMF and furfural) were treated under hydrothermal conditions at 180 °C and were analyzed with respect to their chemical and morphological structures by SEM,13 C solid-state NMR and elemental analysis. This was combined with GC-MS experiments on residual liquor solutions to analyze side products... 

FIGURE 5.1 Cluster model of amylopectin. A and B denote nomenclature of branch chains, 0=reducing end, c.l. = chain length in degree of polymerization. Reprinted from Carbohydrate Research, Vol. 147, Hizukuri (1986), Polymodal distribution of the chain lengths of amylopectin, and its significance, Pages 342-347, with permission from Elsevier. 

Hizukuri, S. (1986). Polymodal distribution of the chain lengths of amylopectin, and its significance. Carbohydr. Res. 147,342-347. 

Manners, D. J. (1989). Recent developments in our understanding of amylopectin structure. Carbohydr. Polym. 11, 87-112. 

Bertoft, E. (2004). On the nature of categories of chains in amylopectin and their connection to the super helix model. Carbohydr. Polym., 57, 211-224. 

Bertoft, E. (2007a). Composition of clusters and their arrangement in potato amylopectin. Carbohydr. Polym., 68, 433 46. 

Hizukuri, S. (1985). Relationship between the distribution of the chain length of amylopectin and the crystalline structure of starch granules. Carbohydr. Res., 141,295-306. 

Noda, T., Takigawa, S., Matsuura-Endo, C., Kim, S. -J., Hashimoto, N., Yamauchi, H., Hanashiro, I., Takeda, Y. (2005). Physicochemical properties and amylopectin structures of large, small, and extremely small potato starch granules. Carbohydr. Polym., 60,245-251. 

Takeda, Y, Hizukuri, S. (1982). Location of phosphate groups in potato amylopectin. Carbohydr. Res., 102, 321-327. 

Takeda, Y, Shibahara, S., Hanashiro, I. (2003). Examination of the structure of amylopectin molecules by fluorescent labeling. Carbohydr. Res., 338,471 75. 

Yusuph, M., Tester, R. F., Ansell, R., Snape, C. E. (2003). Composition and properties of starches extracted from tubers of different potato varieties grown under the same environmental conditions. Food Chem., 82,283-289. Zhu, Q., Bertoft, E. (1996). Composition and structural analysis of alpha-dextrins from potato amylopectin. Carbohydr. Res., 288, 155-174. 

Ortega-Ojeda, F. E., Larsson, H., Eliasson, A. C. (2005). Gel formation in mixtures of hydrophobically modified potato and high amylopectin potato starch. Carbohydr. Polym., 59, 313-327. 

Richardson, S., Nilsson, G. S., Bergquist, K., Gorton, L., Mischnick, P. (2000). Characterisation of the substituent distribution in hydroxypropylated potato amylopectin starch. Carbohydr. Res., 328, 365-373. 

Fredriksson, H., Bjork, L, Andersson, R., Liljeberg, H., Silverio, J., Eliasson, A. -C., Aman, P. (2000). Studies on a-amylase degradation of retrograded starch gels from waxy maize and high-amylopectin potato. Carbohydrate Polymers, 43, 81-87. 

Leeman, A. M., Karlsson, M. E., Eliasson, A. -C., Bjork, I. M. E. (2006). Resistant starch formation in temperature treated potato starches varying in amylose/amylopectin ratio. Carbohydrate Polymers, 65, 306-313. 

Forssell, R, Lahtinen, R., Lahelin, M., Myllarinen, R. (2002). Oxygen permeability of amylose and amylopectin films. Carbohydr. Poly., 47, 125-129. 

Although this article is primarily concerned with gas-liquid chromatography of simple carbohydrates, it is worth noting that certain polysaccharides have been trimethylsilylated. Thus, chlorotrimethyl-silane in pyridine yielded fully trimethylsilylated amylose, cellulose, and pullulan, but failed with dextran and amylopectin.196 Cellulose, amylose, and polyvinyl alcohol have also been trimethylsilylated in molten N-(trimethylsilyl)acetamide.197 As examples of a new class of... 

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