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Wood sweetening

The most important pentose is xylose which can be produced from hardwoods by mild acid hydrolysis. Reduction of xylose gives xylitol, an interesting sweetener because of its ability to prevent dental caries. Industrial production of xylitol from birch wood hydrolyzates started in the 1970s in Finland. An interesting process was developed in which an ion exclusion separation technique is applied for purification and separation of xylose and xylitol from other impurities. Among the corresponding reduction products of hexoses, mannitol, which is also a natural product, has found some use. It can be separated from other alditols by crystallization. Under more drastic... [Pg.193]

Products and Uses Derived from the birch tree or from other wood pulp. It is a nutritive sweetener used in gum, candies, and breath mints. It was recently reported by researchers in Finland that regular doses of the natural sweetener re-... [Pg.287]

C, [ago -75°- -19 (H O) p-DL-xylo-pyranose, OL-form, mp. 129 -131 °C. The L-forms are not natural. An aqueous solution of X. at, e.g., 31 °C, contains 36.5% a-pyranose, 63% )S-pyranose, <1% a-and /3-furanose, and 0.02% aldehyde. X. is obtained technically from the saccharification of wood and from the residues of cellulose production or, respectively, by isolation from xylans or from ears of corn by hydrolysis with dilute acids. Reduction of X. furnishes xylitol which can be used as a sugar substitute. X. itself would also be suitable for use as a sweetener but has only half the sweetness of saccharose and also shows laxative effects. [Pg.708]

Xylitol, a sugar alcohol, has potential use as a natural food sweetener, a dental caries reducer and a sugar substitute for diabetics. It is produced by chemical reduction in alkaline conditions of the xylose derived mainly from wood hydrolyzate (169). The recovery of xylitol from the xylan fraction is about 50-60% or 8-15% of the raw material employed. Drawbacks of the chemical process are the requirements of high pressure (up to 50 atm) and tenq>erature (80-140°C), use of an expensive catalyst (Raney-Nickel) and use of extensive separation and purification steps to remove the by-products that are mainly derived from the hemicellulose hydrolyzate (770). The bulk of xylitol produced is consumed in various food products such as chewing gum, candy, soft drinks and ice cream. It gives a pleasant cool and fresh sensation due to its high negative heat of solution. [Pg.18]

Sweetening of wood to glucose is not economic at present. Previously, the resulting glucose was not recovered as such, but fermented to alcohol. But 49% of the carbon is lost as CO2 in this process. The conversion of glucose to fructose, sorbose, glycerine, or hydroxymethyl furfural is also not economic at present (see Table 24-15). [Pg.386]

Wood can be disintegrated or digested by four methods sweetening the wood, or producing sodium hydroxide pulp, sulfate pulp, or sulfite pulp. [Pg.1107]

In the sweetening of wood, the wood is hydrolyzed at 140-180°C and 6-9 bar with 3-6% sulfuric or hydrochloric acid with 1-2% added SO2. The resulting glucose is not generally recovered as such, but is converted into alcohol. About 10 dm of alcohol is obtained from 100 kg of wood, i.e., 17% of the formula yield. Furfurol, aliphatic ketones, and aldehydes occur as by-products. [Pg.1107]

Galactitol accumulates In people with galactosaemia. Xylitol is the sugar alcohol form of xylose. It is extracted from birch wood and is also called wood sugar . Xylitol is used as an anticariogenic sweetener in chewing gum... [Pg.47]

Prod, industrially by hydrol. of wood. Found mainly in the form of Xylan or as glycosides. Present in wood (maple and cherry), straw, corncobs, cottonseed hulls and pecan shells. Sweetener. Inexpensive starting material for synthesis. Diagnostic aid (intestinal function determination). [Pg.979]

Arabinogalactan, due to its good solubility and low viscosity, is used as an emulsifier and stabi-Coniferous larch-related woods Larix species lizer, and as a carrier substance in essential oils, similar to pine, but shed their needle-like leaves) formulations, and sweeteners. [Pg.313]


See other pages where Wood sweetening is mentioned: [Pg.340]    [Pg.159]    [Pg.31]    [Pg.926]    [Pg.252]    [Pg.104]    [Pg.307]    [Pg.511]    [Pg.11]    [Pg.215]    [Pg.143]    [Pg.243]    [Pg.392]    [Pg.1387]    [Pg.606]    [Pg.386]    [Pg.386]    [Pg.159]    [Pg.425]    [Pg.761]    [Pg.1168]    [Pg.159]    [Pg.931]    [Pg.405]   
See also in sourсe #XX -- [ Pg.1107 ]




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Sweetening

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