Fructose separation

The fructose solution was decolorized by treatment with activated charcoal and concentrated under vacuum to a thick syrup. Two volumes of hot 95% ethyl alcohol were added, and the solution was heated to a boil and filtered to remove a small amount of insoluble material. After cooling, three volumes of ethyl ether were added, and the solution was allowed to stand overnight in the refrigerator. Fructose separated from the solution as a thick syrup and was... 

Fructose separation adsorbents, 7 587t liquid adsorption, 7 665, 674 with zeolite KX, 7 610 Fructosyloligosaccharides (FOS), 23 480 Fruit(s)... 

The separation of the two sugars fructose and glucose, is currently perhaps the industrial separation of biomolecules performed on the largest scale. Since it is a typical two-component separation, the advantages of utilizing an SMB for this purpose are obvious and glucose/fructose separations by SMB are well estab-... 

The technology of SMB chromatography has been widely used in the petrochemical (xylene isomer separation) and food industries (glucose-fructose separation) in... 

Glucose-Fructose separation using SMB and Varicol Processes Two cases (a) maximization of both purity and productivity of fructose, and (b) maximization of productivity of both glucose and fructose. NSGA Both operation and design optimization were studied. This is one of the three applications presented in Yu et ol. (2004). Subramani et d. (2003a) Yu et d. (2004)... 

Subramani, H. J., Hidajat, K. and Ray, A. K. (2003a). Optimization of simulated moving bed Varicol processes for glucose-fructose separation, Trans IChemE., 81, pp. 549-567. 

In sucrose the fructose unit exists as a 5-membered ring, but on hydrolysis to invert sugar the fructose separates as a 6-membered ring. Maltose contains two molecules of J-glucose, as does cellobiose (from the hydrolysis of acetyl cellulose) but in a different configuration. The synthesis of sucrose was claimed by Pictet and H. Vogel, but this was doubted a definite synthesis from glucopyranose and fructofuranose derivatives was achieved by Lemieux (1953-6). 

Esters of sorbitol, sucrose, glucose, and fructose separation by number of acyl groups... 

The use of a ternary mixture in the drying of a liquid (ethyl alcohol) has been described in Section 1,5 the following is an example of its application to the drying of a solid. Laevulose (fructose) is dissolved in warm absolute ethyl alcohol, benzene is added, and the mixture is fractionated. A ternary mixture, alcohol-benzene-water, b.p. 64°, distils first, and then the binary mixture, benzene-alcohol, b.p. 68-3°. The residual, dry alcoholic solution is partially distilled and the concentrated solution is allowed to crystallise the anhydrous sugar separates. 

The conversion of the compounds under investigation into coloured derivatives (e.g., the separation of carbonyl compounds by conversion into their 2 4-dinitrophenylhydrazones, etc. of hydrocarbons through their picrates of alcohols through their 3 5-dinitrobenzoates of glucose, fructose and other simple sugars through their p-phenylazobenzoyl esters). 

In a 50-100 ml. conical flask place a solution of 0 -5 g. of glucose in 5 ml. of water, 12-15 ml. of 10 per cent, sodium hydroxide solution and 1 ml. of benzoyl chloride, cork tightly, and shake until the odour of benzoyl chloride has disappeared and a crystalline (frequently sticky) soUd has separated. Filter oflF the solid, wash it with a Uttle water, and recrystaUise it from ethyl or n-butyl alcohol. (If the product is sticky, it should be removed, and spread on a porous tile before recrystaUisation.) Glucose pentabenzoate has m.p. 179°. Fructose pentabenzoate, m.p. 78-79°, may be similarly prepared. 

Dissolve 0-2 g. of fructose in 10 ml. of water, add 0-6 g. of cw-methyl-phenylhydrazine and sufficient rectified spirit to give a clear solution. Since the fructose may not be quite pure, warm the mixture slightly, allow to stand, preferably overnight, so that any insoluble hydrazones may separate if present, remove them by filtration. Add 4 ml. of 50 per cent, acetic acid to the filtrate it will become yellow in colour. Heat the solution on a water bath for 5-10 minutes, and allow to stand in the dark until crystalUsation is complete it may be necessary to scratch the walls of the vessel to induce crystalUsation. Filter the crystals and wash with water, followed by a little ether. RecrystaUise the orange-coloured methylphenylosazone from benzene m.p. 152°. 

Fig. 5. Fructose—glucose separation on faujasite adsorbents, (a) Ca—Y adsorbent (b) Ca—X adsorbent (c) K—X adsorbent.

Fructose—Dextrose Separation. Emctose—dextrose separation is an example of the appHcation of adsorption to nonhydrocarbon systems. An aqueous solution of the isomeric monosaccharide sugars, C H 2Dg, fmctose and dextrose (glucose), accompanied by minor quantities of polysaccharides, is produced commercially under the designation of "high" fmctose com symp by the enzymatic conversion of cornstarch. Because fmctose has about double the sweetness index of dextrose, the separation of fmctose from this mixture and the recycling of dextrose for further enzymatic conversion to fmctose is of commercial interest (see Sugar Sweeteners). 

Table 6. Separation of Fructose from High Fructose Com Symp, Pilot-Plant Scale...

Ligand exchange Equihbrium Chromatographic separation of glucose-fructose mixtures with Ca-form resins Removal of hea y metals with chelating resins Affinity chromatography... 

Displacement-purge forms the basis for most simulated continuous countercurrent systems (see hereafter) such as the UOP Sorbex processes. UOP has licensed close to one hundred Sorbex units for its family of processes Parex to separate p-xylene from C3 aromatics, Molex tor /i-paraffin from branched and cyclic hydrocarbons, Olex for olefins from paraffin, Sarex for fruc tose from dextrose plus polysaccharides, Cymex forp- or m-cymene from cymene isomers, and Cresex for p- or m-cresol from cresol isomers. Toray Industries Aromax process is another for the production of p-xylene [Otani, Chem. Eng., 80(9), 106-107, (1973)]. Illinois Water Treatment [Making Wave.s in Liquid Processing, Illinois Water Treatment Company, IWT Adsep System, Rockford, IL, 6(1), (1984)] and Mitsubishi [Ishikawa, Tanabe, and Usui, U.S. Patent 4,182,633 (1980)] have also commercialized displacement-purge processes for the separation of fructose from dextrose. 

Fig. 1 Schematic diagram of the chromatographic separation (A) and the fluorescence scan (B) of a sugar mixture containing 1 pg substance per chromatogram zone. Lactose (1), fructose (2), arabinose (3), xylose (4), rhamnose (5), mixture (G).

Fig. 2 Fluorescence plots of the sugars after separation on a Si-50 000 layer without ammonia-vapor treatment. Start (1), raffinose (2), lactose (3), sucrose (4), glucose (5), fructose (6).

The selective separation range of P-6/S-200 was determined with Blue Dextran (Vexdi exclusion limit) and fructose (V,o total permeation limit). Molecular weight (degree of polymerization) calibration (Fig. 16.22) was established with dextran standards and low dp pullulans (dp 3, 6, 9, 12, 15, 18) formed by the controlled hydrolysis of high dp pullulan. 

The calcium levulate precipitate was separated from the reaction mixture by filtration and washed with cold water. The precipitate was suspended in water to give a thick slurry, and solid carbon dioxide added until the solution was colorless to phenolphthalein. A heavy precipitate of calcium carbonate was now present and free fructose remained in the solution. 

The separation was carried out on a TSKgel Amide-80 column 4.6 mm i.d. and 25 cm long with a mobile phase consisting of a 80% acetonitrile 20% water mixture. The flow rate was 1 ml/min and the column was operated at an elevated temperature of 80°C. The saccharides shown were 1/ rhamnose, 2/ fucose, 3/ xylose, 4/ fructose, 5/ mannose, 6/ glucose, 7/ sucrose and 8/ maltose. The analysis was completed in less than 20 minutes. These types of separations including other biomonomers, dimers and polymers are frequently carried out employing refractive index detection. 

The dominant interactions that take place with this novel phase are not clear. There will obviously be dispersive interactions with the propyl chain and some polar interactions with the amino group. Whether there are ionic interactions taking place as well is uncertain but, nevertheless, the material affects an excellent separation of glucose and fructose and this remains a baseline separation even when the two sugars are both present at about the 5% level. 

Fig. 1 (A) Chromatographic separation of sugars. Track 1 fructose, 2 sucrose, 3 glucose, 4 mixture of the substances in tracks 1-3, 5 mixture of substances in tracks 1-3 and 6, 6 Fructo-oligosaccharides, 7 1-kestose, 8 mixture of glucose, maltose, maltotriose and maltotetraose. (B) Absorption scan of track 5 with 200 ng each substance per chromatogram zone 1 = fructosyl-nystose, 2 = nystose, 3 = 1-kestose, 4 = fructose, 5 = sucrose, 6 = glucose.

Figure 17-2. The pathway of glycolysis. ( ,—P, HOPOj " .inhibition.) At asterisk Carbon atoms 1-3 of fructose bisphosphateform dihydroxyacetone phosphate, whereas carbons 4-6 form glyceraldehyde 3-phosphate. The term "bis-," as in bisphosphate, indicates that the phosphate groups are separated, whereas diphosphate, as in adenosine diphosphate, indicates that they are joined.

Inorganic iron is absorbed only in the (reduced) state, and for that reason the presence of reducing agents will enhance absorption. The most effective compound is vitamin C, and while intakes of 40-60 mg of vitamin C per day are more than adequate to meet requirements, an intake of 25-50 mg per meal will enhance iron absorption, especially when iron salts are used to treat iron deficiency anemia. Ethanol and fructose also enhance iron absorption. Heme iron from meat is absorbed separately and is considerably more available than inorganic iron. However, the absorption of both inorganic and heme iron is impaired by calcium—a glass of milk with a meal significantly reduces availabiUty. 

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