Xylitol 87-99-0 manufacturer

Xylitol 87-99-0 in stock

Xylitol 87-99-0 price

EINECS number: 201-788-0

Molecular formula: C5H12O5

MDL number: MFCD00064292

Molecular Weight: 152.15

Mol file: 87-99-0.mol

Category: Food Additives: Flavor (flavor enhancer) : Sweetener

Appearance properties: the appearance of sugar slightly sweet rhombic crystal (stable type) or monoclinic crystal (metastable type). Melting point of rhombic crystal is 61-61.5℃. Monoclinic crystals have melting points of 93-94.5℃ and boiling points of 215-217℃. Soluble in water, ethanol and pyridine solvents.

Density: 1.52

Melting point: 93 ~ 94.5℃

USES:

1. Xylitol can be used as a food flavoring agent

2. Xylitol is a kind of special sweetener with nutritional value. Soluble in water to absorb heat, edible taste cool, and not caries, also suitable for diabetes use. China's regulations can be used in cakes, drinks, candy, to replace sucrose, according to the production needs of appropriate use.

3. Nutritional sweetener, mainly for diabetic patients and as anti-caries sweetener. Moisturizing factor.

4. Xylitol is an organic synthetic raw material, which can be used to produce surfactants, emulsifiers, demulsifiers, various alkyd resins, coatings, varnishes, etc. And synthetic fatty acid esters are not volatile plasticizers. Xylitol can replace glycerol and is used in paper making, daily necessities and national defense industry. Because it is a polyhydroxyl compound, it has sweet taste, non-toxic, suitable for low calorific value food and diabetics as a sweetener.

The preparation methods

Method one:

The industrial production of xylitol is from the polypentose contained in agricultural processing wastes (such as corn cob, cottonseed husk, bagasse and rice husk) through acid hydrolysis to pentose, and then through catalytic conversion to xylitol:

(C5H8O4) n + H2O [H +] - n CH10O5 (H2) and HOCH2 ch2oh (CHOH) 3

The pretreatment of raw corn cob is in - tank pretreatment and outside - tank pretreatment. Extra-tank pretreatment is to remove the mechanical impurity in raw materials and improve the quality of raw materials through screening, winding, washing and other processes. The pretreatment in the tank includes water treatment, acid treatment or alkali treatment.

Corn cob in water treatment of the most suitable conditions for 120℃ and 2h.

Hydrolysis There are two types of hydrolysis operation processes:

That is, dilute acid normal pressure hydrolysis (sulfuric acid concentration 1.5% ~ 2.0%, temperature 100 ~ 105℃) and low acid pressure hydrolysis (sulfuric acid concentration 0.5% ~ 0.7%, temperature 120 ~ 125℃). General a corn cob 700kg(equivalent to 590kg dry material), add sulfuric acid 100kg(according to 100%), acid consumption per kilogram of sugar 0.48 ~ 0.75kg, hydrolysis time 2 ~ 3h.

The purpose of neutralization is to remove sulfuric acid in hydrolysate, but to retain organic acids.

Commonly-used neutralizer is lime, which is first matched into lime milk with a relative density of 1.10 ~ 1.15. After constant stirring and adding lime milk at 80℃, the pH value of hydrolysate was increased from 1.0 ~ 1.5 to 3.5 for about 1h. After precipitation for 2h, the neutralization operation was completed. At this time, the content of inorganic acid in the neutralization solution is generally 0.03% ~ 0.08%, and the sugar loss is controlled below 3%.

Decolorization, evaporation and ionization neutralization solution need to be decolorized, evaporated and concentrated, and ionic resin exchange and other processes to produce a pure xylose solution. The decolorization loss is 3% ~ 5%. The quality of decolorization solution is above 80% transmittance, 75% ~ 80% purity, and 0.18% ~ 0.22% ash content.

The decolorization solution is concentrated to 35%~40% sugar content in the central circulating tube evaporator, where the trace inorganic acid in the decolorization solution can be removed by evaporation, and the calcium sulfate precipitate precipitated during evaporation can be removed by filtration.

The purity of concentrated solution is usually only 85%. The purity of xylose solution is 95% ~ 97% by ion exchange with 732 strong acid cationic resin and strong alkali polycrystalline anion resin (1:1.5).

Hydrogenation of xylose and crystallization of xylitol Hydrogenation of xylose containing 12% ~ 15% sugar was prepared by using a high pressure feed pump after pH value of xylose containing 12% ~ 15% sugar was adjusted with alkaline solution to 8, preheated to 90℃, and then hydrogenated at 115-130 ℃ and 7.0 ~ 8.0MPa to obtain a hydrogenated solution containing 12% ~ 15% alcohol. The requirements of hydrogenation solution: refractive index 12% ~ 15%, total acid 0.015% ~ 0.05%, residual sugar 0% ~ 1.5%, ash 0.1% ~ 0.2%, transmittance 80% ~ 85%. The hydrogenated solution was decolorized and filtered with 0.2%(for alcohol) activated carbon, and preconcentrated to 50% alcohol, and then further concentrated to 88% alcohol xylitol paste after filtration. After discharging, it was cooled slowly from 65 ~ 70℃ (1℃/h) to 20~30℃, centrifuged to obtain crystals containing 96% alcohol, and the mother liquor was reused.

Method 2:

By corn cob or bagasse after hydrolysis, purification, hydrogenation, refined.

Candida WQ-1 strain (selected by Wuxi University of Light Industry) was produced by fermentation method. The average conversion rate is 70%, and the average production intensity is 2.27g/(L? H).

Method 3:

The polypentose contained in agricultural products (such as corn cob, cottonseed husk, bagasse and rice husk) was hydrolyzed into xylose by acid hydrolysis, and then refined, then hydrogenated in the presence of sodium amalgam catalyst to produce crude xylitol, and then concentrated, crystallized and separated to obtain crystalline xylitol.