Sugar alcohols mannitol

Fig. 11 Sugar alcohols. Mannitol, crystalline (A), mannitol, spray dried (B), and sorbitol-instant, spray dried (C).

Sugar alcohols mannitol and xylitol are used as sweeteners [113]. Mannitol also has some medical uses [114]. Mannitol is produced in a single step from D-fructose by mannitol dehydrogenase. In one E. coli system, reducing power from formate was used and D-fructose was converted to mannitol with 84% molar yield and final titer about 66 g 1 [115]. 

In the Phaeophyceae (brown algae), the food reserves are laminarin, a water-soluble P-D-(l- 3)-linked D-glucan and a sugar alcohol, mannitol. Laminarin contains 20-25 glucose units (Percival, 1970, 1979). 

Gluconobacter can utilize sugar alcohols (mannitol, sorbitol, or glycerol) or hexoses (glucose or fructose) as carbon sources. Acids are formed from propanol, butanol, glycerol, erythritol, mannitol, arabinose, ribose, fructose, galactose, mannose, and maltose by a majority of strains (De Ley and Swings, 1984). 

Bulking sweeteners provide a bulking effect, along with some of the sweetness and functional properties of sugar. They may be used alone to replace sugar in appHcations that can tolerate some reduction in sweetness. Products that fall into this category include mannitol [69-65-8], a sugar alcohol... 

Polarimetric analysis of sorbitol and mannitol in the presence of each other and of sugars is possible because of their enhanced optical rotation when molybdate complexes are formed and the higher rotation of the mannitol molybdate complex under conditions of low acidity (194). The concentration of a pure solution of sorbitol may be determined by means of the refractometer (195). Mass spectra of trimethylsilyl ethers of sugar alcohols provide unambiguous identification of tetritols, pentitols, and hexitols and permit determination of molecular weight (196). 

The 1995 Canadian and United States sugar alcohol (polyol) production is shown in Table 2. The market share of each is also given. Liquids comprise 48% crystalline product comprises 39% and mannitol comprises 13% of the polyol market. An estimate of total U.S. sorbitol capacity for 1995 on a 70% solution basis was 498,000 t. ADM, Decatur, lU., produced 68,200 t Ethichem, Easton, Pa., 13,600 t Lon2a, Mapleton, lU., 45,400 t Roquette America, Gurnee, lU., 68,200 t and SPI Polyols, New Castle, Del., 75,000 t (204). Hoffman-LaRoche, which produces sorbitol for captive usage in the manufacture of Vitamin C (see Vitamins), produced about 27,300 t in 1995. 

Toxicity. Sugar alcohols are classified as relatively harmless. Acute oral toxicity values in mice for mannitol and sorbitol (5) are given in Table 4. The acute oral LD q value for xyUtol in mice is 25.7 g/kg (205). Ingestion of 10 g/d of either mannitol or sorbitol by a normal human subject for one month resulted in no untoward effects (206). XyUtol given to healthy humans for 21 d in increasing doses up to 75 g/d produced no adverse effects (207). The limiting dose of xyUtol for production of diarrhea in humans is 20—30 g (4), but tolerance usually develops on continued adrninistration (207). 

Sweetness is often an important characteristic of sugar alcohols in food and pharmaceutical applications. The property of sweetness is measured in a variety of ways and has a corresponding variability in ratings (218). Based on one or more test methods, erythritol and xyfitol are similar to or sweeter than sucrose (218,219). Sorbitol is about 60% as sweet as sucrose, and mannitol, D-arabinitol, ribitol, maltitol, isomalt, and lactitol are generally comparable to sorbitol (see Sweeteners). 

Reduction. Mono- and oligosaccharides can be reduced to polyols (polyhydroxy alcohols) termed alditols (glycitols) (1) (see Sugar alcohols). Common examples of compounds in this class ate D-glucitol (sorbitol) [50-70-4] made by reduction of D-glucose and xyhtol [87-99-0] made from D-xylose. Glycerol [56-87-5] is also an alditol. Reduction of D-fmctose produces a mixture of D-glucitol and D-mannitol [69-65-8],... 

The sugar alcohols sorbitol (hR, 15 — 20), mannitol (hRf 20—25) and xylitol hRf 30 — 35) appeared as light to dark brown chromatogram zones on a beige-colored background. The detection limits were 1 ng substance per chromatogram zone. 

Adding a hydrogen or two to a sugar makes a sugar alcohol. The sugar alcohols xylitol, maltitol, sorbitol, and mannitol are all used as sweeteners in food. They are not absorbed well by the body, and they don t have as many calories as sugar. As with any... 

Mannitol is a sugar alcohol. It has half the calories of sugar and is half as sweet. It is poorly absorbed by the body, so it does not raise insulin levels as much as sugar does. It does not promote tooth decay. 

Maltitol is a sugar alcohol like sorbitol, mannitol, and xylitol, but it is a larger molecule. Unlike those other sugar alcohols, and menthol, maltitol does not stimulate the cold sensors in the skin, so it does not feel cool in the mouth. 

Hydrogenated starch hydrosylate is a mixture of several polyols, or sugar alcohols, such as sorbitol, maltitol, and mannitol, among others. 

As described above, understanding the mechanism of the dispersion increase is a difficult task. In this work we compare a catalyst prepared by cobalt nitrate impregnation onto alumina with one modified by the addition of mannitol, and use TGA and in situ microscopy to investigate the increased dispersion. Mannitol is a sugar alcohol that is structurally similar to sorbitol [31], as shown in Figure 1.1. 

Sugar alcohols (6) such as sorbitol and mannitol do not play an important role in animal metabolism. 

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