Title: Alternative Sweeteners

Cyclamate 65
III. PHYSICAL CHARACTERISTICS (13–16)
Cyclamic acid, or cyclohexylsulfamic acid (C 6H 13NO 3S; MW 179.24), is a
white crystalline powder, with a melting point of 169–170°C, good aqueous solubility
(1 g/7.5 ml), and a lemon-sour sweetness. It is a strong acid, and the pH
of a 10% aqueous solution is about 0.8–1.6. Sodium and calcium cyclamate are
strong electrolytes, which are highly ionized in solution, fairly neutral in character,
and have little buffering capacity. Both salts exist as white crystals or white
crystalline powders. The molecular weight of the sodium salt (C6H12NO3S⋅Na)
is 201.22 and that of the calcium salt (C 12H 24N 2O 6S 2⋅Ca) is 396.54 (432.58 as the
dihydrate). They are freely soluble in water (1 g/4–5 ml) at concentrations far
in excess of those required for normal use but have limited solubility in oils and
nonpolar solvents. Cyclamate solutions are stable to heat, light, and air throughout
a wide pH range.
Cyclohexylamine, which is the starting material in the synthesis of cyclamate
and is also a metabolite of cyclamate, has distinctly different properties.
Cyclohexylamine (MW 99.17) is a base, not an acid; it has a fishy odor and
a bitter taste, not a sweet taste. It is a clear colorless liquid, which is miscible
with water, alcohol, and nonpolar solvents and has a boiling point of 134.5°C. The
pH of a 0.01% aqueous solution is 10.5. Cyclohexylamine has many industrial
applications, including use in water treatment and rubber acceleration.
IV. RELATIVE SWEETNESS AND UTILITY
In contrast to the sweet taste from sucrose, which appears quickly and has a
sharp, clean cut-off, the sweetness from cyclamate builds to its maximal level
more slowly and persists for a longer time (13). Cyclamate is generally accepted
as being 30 times sweeter than sucrose, but the relative sweetness of cyclamate
tends to decrease at higher sweetness intensities. For example, cyclamate is about
40 times as sweet as a 2% sucrose solution but only 24 times as sweet as a 20%
sucrose solution (13). This trend may be at least partially due to the increasing
levels of bitterness and aftertaste that characteristically appear at very high cyclamate
concentrations (3). This off-taste is, however, not a problem at normal use
concentrations.
Calcium cyclamate is somewhat less sweet than sodium cyclamate, and the
off-taste response starts at a lower concentration of the calcium salt than of the
sodium salt. Vincent et al. (3) suggested that the differences between the two
salts might be related to differences in ionization because the sweet taste is due
to the cyclamate ion, whereas the off-taste may be associated with the undissociated
salt. The sweetening power of cyclamate also varies with the medium, and