Title: Alternative Sweeteners

90 Borrego and Montijano
example in the leaves of Lithocarpus litseifolius, a variety of sweet tea from
China (20). Other sweet dihydrochalcones were detected in the fruit of Iryanthera
laevis, which is used in the preparation of a Colombian sweet food (21). As a
recent example of occurrence in processed foods, dihydrochalcone glycosides
have been detected and quantified in different apple juices and jams at levels up
to 15 ppm in an apple compote (22).
III. PHYSICAL PROPERTIES AND STABILITY
Neohesperidine DC is an off-white crystalline powder. The crystals are monoclinic,
space group P2 1. X-ray diffraction demonstrated that the molecule is more
or less J-shaped with the β-neohesperidosyl residue forming the curved part of
the J and the hesperetin dihydrochalcone aglycone forming the linear segment
(23, 24).
The solubility of neohesperidine DC in distilled water at room temperature
is low (0.4–0.5 g/l), being freely soluble both in hot (80°C) water and aqueous
alkali. As with other citrus flavonoids (hesperidin, naringin), it exhibits higher
solubility in an alcohol-water mixture than in water or ethanol alone (25). Several
methods for solubility enhancement have been described in the patent literature,
such as preparation of the sodium and calcium salts (26) and combinations with
water-soluble polyols such as sorbitol (27, 28). Solubility in water may also be
enhanced when administered in propylene glycol or glycerol solutions (29). In
any case, because it is used at low concentrations, the solubility in cold water is
not a limitation for application in food and beverages (30).
Stability studies on neohesperidine DC have shown that the product can
be stored for more than 3 years at room temperature without any sign of decomposition.
It is slightly hygroscopic taking up water in a saturated environment up
to a maximum of 15% (unpublished observations).
In liquid media and under certain conditions of high temperature and low
pH, the glycosidic bonds are hydrolyzed, forming the aglycone hesperetin dihydrochalcone,
glucose, and rhamnose (Fig. 2).
The stability of neohesperidine DC in aqueous model systems at various
pHs and temperatures has been studied (31–33). Aqueous solutions at room temperature
are quite resistant to hydrolysis to the free sugars and the aglycone as
long as the pH does not fall below 2. (Even if hydrolysis were to occur, there
would not be complete loss of sweetness because the aglycone, hesperetin dihydrochalcone,
is itself sweet, although not very soluble). The degradation of neohesperidine
DC was studied at pH values from 1 to 7 and temperatures ranging
from 30° to 60°C for up to 140 days (33). The hydrolysis of neohesperidine DC
could be represented as a first-order reaction across the range of temperatures
and pHs tested. Optimum pH was 4, although half-life values indicate that no