Fructose physical properties

Secalin. Secalin has been isolated from the stems of unripe rye.46,68 Schlubach and Bandmann69 studied its structure. The great difficulty they encountered in obtaining the polysaccharide and its acetate in homogeneous form made the determination of physical properties uncertain. However, by hydrolysis of the methyl derivative, they obtained, after separation by means of the /3-naphthoates, tetramethyl-, trimethyl-, and dimethyl-D-fructoses in the proportions of 1 2 1. The trimethyl-D-fructose was identified as 1,3,4-trimethyl-D-fructofura-nose by its melting point and specific rotation. 

The same conclusion can be drawn from the physical properties of the hexaacetate of di-D-fructose anhydride, which has thus far been obtained only in the form of plastic sheets resembling glass. Table I compares the melting points and specific rotations of other di-D-fructose anhydride hexaacetates reported in the literature. 

Table II Physical properties of aqueous fructose solutions at 20°C.

El-Maghrabi, M.R. Correia, J.J. Heil, P.J. Pate, T.M. Cobb, C.E. Pilkis, S.J. Tissue distribution, immimoreactivity, and physical properties of 6-phos-phofructo-2-kinase/fructose-2,6-bisphosphatase. Proc. Natl. Acad. Sci. USA, 83, 5005-5009 (1986)... 

Recently, much attention has been given to the production of liquid sweeteners as an alternative to cane sugar using inexpensive starch-containing natural materials as the primary feed stock. This situation exists in the United States as this country is not self sufficient in the production of cane, but must rely heavily on importation mainly from South America and the Caribbean. The main source of sta rch in the United States comes from corn (Zea mays) and the liquid sweetener commercially produced from this material is called high fructose corn syrup (HFCS). The current method of production of HFCS is via wet milling which exploits the physical properties of the whole corn constituents (oil, starch, gluten, and fiber) for their separation coupled with enzymatic hydrolysis of the starch fraction to monosaccharides. 

Two compounds can have different structures because of a differing arrangement of the some groups in the positional isomerism (e.g. midine vs. pseudouridine). Compounds with the same molecular formula but with different functional groups are structural isomers (e.g. D-glucose vs. D-fructose) in structural isomerism. Positional isomers and structural isomers have different chemical and physical properties because of the different arrangement of the atoms. These two types of isomers (i.e. positional isomers and structural isomers), which differ in the manner in which atoms are connected or bonded together, are also called constitutional isomers. 

Wungtanagom, R. and Schmidt, S.J. 2001. Thermodynamic properties and kinetics of the physical aging of amorphous glucose, fructose, and their mixture. J. Therm. Anal. Calorim. 65, 9-35. 

With the acquisition of the Thomson plant and technology, and the construction of their own plant in Lafayette, Indiana, in the late 1980s, the A. E. Stanley Manufacturing Company dramatically increased crystalline fmctose production. On the strength of a growing appreciation for crystalline fructose s unique physical and functional properties, its competitive pricing, and its successful penetration of specific mainstream food applications, woddwide crystalline fmctose production grew to more than 50,000 metric tons by 1992. In the same time period, crystalline fmctose prices fell dramatically to ca... 

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