Xylit Chemische Eigenschaften,Einsatz,Produktion Methoden
R-S?tze Betriebsanweisung:
R36/37/38:Reizt die Augen, die Atmungsorgane und die Haut.
S-S?tze Betriebsanweisung:
S24/25:Berührung mit den Augen und der Haut vermeiden.
S36:DE: Bei der Arbeit geeignete Schutzkleidung tragen.
S26:Bei Berührung mit den Augen sofort gründlich mit Wasser abspülen und Arzt konsultieren.
Chemische Eigenschaften
The solubility of D-xylitol (D-xylopentan-1.2.3.4.5-pentaol) in water is approximately
1,690 g/L at room temperature. Xylitol is stable under the common processing
conditions of foods.
Xylitol is, depending on the concentration, similarly or slightly sweeter than
sucrose and noncariogenic.
In the European Union, xylitol is approved as E 967 for a large number of food
applications. In the United States, it is approved for use in foods following Good
Manufacturing Practice and it is also approved in many other countries.
History
Xylitol is equally as sweet as sucrose. This property is of advantage to food processors because in reformulating a product from sucrose to xylitol, approximately the same amounts of xylitol can be used. Because xylitol has a negative heat of solution, the substance cools the saliva, producing a perceived sensation of coolness, quite desirable in some food products, notably beverages. Recently, this property has been used in an iced-teaflavored candy distributed in the European market. As of the late 1980s, 28 countries have ruled positively in terms of xylitol for use in commercial products. Xylitol has been found particularly attractive for use in chewing gum, mint and hard candies, and as a coating for pharmaceutical products. Xylitol has the structural formula shown below, with a molecular weight of 152.1. It is a crystalline, white, sweet, odorless powder, soluble in water and slightly soluble in ethanol and methanol. It has no optical activity.
Verwenden
A polyol substrate for xylitol and sorbitol dehydrogenases.
Vorbereitung Methode
Xylitol occurs naturally in many fruits and berries, although
extraction from such sources is not considered to be commercially
viable. Industrially, xylitol is most commonly derived from various
types of hemicellulose obtained from such sources as wood, corn
cobs, cane pulp, seed hulls, and shells. These materials typically
contain 20–35% xylan, which is readily converted to xylose (wood
sugar) by hydrolysis. This xylose is subsequently converted to
xylitol via hydrogenation (reduction). Following the hydrogenation
step, there are a number of separation and purification steps that
ultimately yield high-purity xylitol crystals. The nature of this
process, and the stringent purification procedures employed, result
in a finished product with a very low impurity content. Potential
impurities that may appear in small quantities are mannitol,
sorbitol, galactitol, or arabitol.
Less commonly employed methods of xylitol manufacture
include the conversion of glucose (dextrose) to xylose followed by
hydrogenation to xylitol, and the microbiological conversion of
xylose to xylitol.
Definition
ChEBI: A pentitol (five-carbon sugar alcohol) having meso-configuration, being derived from xylose by reduction of the carbonyl group.
Allgemeine Beschreibung
Xylitol is a naturally occurring five carbon sugar alcohol, equivalent to sucrose in sweetness. Xylitol finds applications in the preparation of confectionaries, chewing gum, toothpaste and mouthwashes. Xylitol is a low-energy sweetener with insulin independent metabolism, making it a promising alternative for sugar in diabetic patients. Xylitol is a natural anticaries agent used in the treatment of dental caries, as it is not utilized by cariogenic bacteria creates a starvation effect on them. Xylitol prevents otitis and upper respiratory tract infections. Commercially, microorganisms like bacteria, fungi and yeasts produce xylitol by fermentation.
Sicherheitsprofil
Very low toxicity by
ingestion. When heated to decomposition it
emits acrid smoke and irritating fumes. A
sugar.
Lager
Xylitol is stable to heat but is marginally hygroscopic. Caramelization
can occur only if it is heated for several minutes near its boiling
point. Crystalline material is stable for at least 3 years if stored at
less than 65% relative humidity and 25℃. Milled and specialized
granulated grades of xylitol have a tendency to cake and should
therefore be used within 9 to 12 months. Aqueous xylitol solutions
have been reported to be stable, even on prolonged heating and
storage. Since xylitol is not utilized by most microorganisms, products made with xylitol are usually safe from fermentation and
microbial spoilage.
Xylitol should be stored in a well-closed container in a cool, dry
place.
Inkompatibilit?ten
Xylitol is incompatible with oxidizing agents.
Regulatory Status
GRAS listed. Approved for use as a food additive in over 70
countries worldwide, including Europe, the USA and Japan.
Included in the FDA Inactive Ingredients Database (oral solution,
chewing gum). Included in nonparenteral medicines licensed in the
UK and USA. Included in the Canadian List of Acceptable Nonmedicinal
Ingredients.
Xylit Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
