Title: Alternative Sweeteners

284 Kato and Moskowitz
cation and concentration, is hydrogenated by means of a nickel or other transition
metal catalyst. After additional purification steps to remove the starting materials
and catalyst, the solution is concentrated to syrup, then crystallized (3). Maltitol
may also contain trace or quite low levels of sorbitol, maltotriitol, and higher
hydrogenated oligosaccharides. Currently, there are two kinds of crystalline maltitol
powders on the market with minimum maltitol contents of 92.5% and 98%
that are produced and marketed worldwide.
III. PHYSICAL CHARACTERISTICS
The structure of maltitol (alpha(1-4)-glucosylsorbibtol) has been confirmed by
nuclear magnetic resonance and infrared absorption studies as a crystalline polyhydric
alcohol obtained by the catalytic hydrogenation of maltose, a disaccharide
consisting of two glucose units linked by means of an alpha(1-4) bond (Fig. 1).
Crystallographic studies have also demonstrated that the molecular structure is
a fully extended conformation with no intramolecular hydrogen bonding; all nine
hydroxyl groups are involved in intermolecular hydrogen bonds and in bifurcated,
finite chains (3).
Maltitol exhibits a negligible cooling effect in the mouth given its negative
heat of solution (23 kJ/kg), which is close to that of sucrose (18 kJ/kg),
and much less than that of other carbohydrates: xylitol (153 kJ/kg), mannitol
(121 kJ/kg), sorbitol (111 kJ/kg), isomalt (39 kJ/kg), and dextrose
(104.6 kJ/kg).
Figure 1 (a) Chemical structure for maltose. (b) Chemical structure for maltitol.