Food Chemistry

440 8 Food Additives

and the thiocarbamoyl compound are also sweet.

(8.11)

8.8.12.2 Guanidines

Derivatives of guanidinoacetic acid (For-
mula 8.12) are among the sweetest compounds

known until now (Table 8.8).

(8.12)

Replacement of the carboxyl group by a tetrazole
residue results in loss of sweetening strength (Ta-
ble 8.8).
The guanidines can be synthesized, e. g., via the
isothiocyanates:

(8.13)

Table 8.8.Taste of some guanidines (Formula 8.12)

RR^1 R^2 fsac, g( 2 )

p-Cyanophenyl H Carboxy- 2700
methyl
Benzyl 30 , 000
Phenylsulfonyl 45 , 000
1-Naphthyl 60 , 000
Cyclohexyl 12 , 000
Cyclooctyl 170 , 000
Cyclononyl 200 , 000
3,5-Dichloro- Benzyl 80 , 000
phenyl Cyclooctyl 60 , 000
p-Cyanophenyl Cyclohexyl Tetrazolyl- 400a
methyl
Cyclooctyl 5000 b
af
sac, g(^4 ).
bf
sac, g(^5 ).

8.8.13 Oximes

It has long been known that the anti-aldoxime

of perillaldehyde (discovered in the essential oil

ofPerilla nankinensis) has an intensive sweet

taste (fsac, g∼2000). For its structure see For-

mula 8.14 (I).

(8.14)

In the meantime, a related compound, (II), with

improved solubility, has been reported, but its

sweetness is just moderately high (fsac, g∼450).

8.8.14 Oxathiazinone Dioxides

These compounds (Formula 8.15) belong to

a class of sweeteners with an AH/B-system

corresponding to that of saccharin. Based on their

properties and present toxicological data, they are

suitable for use. The sweetening strength depends

on substituents R^1 and R^2 and isfac, g( 10 )= 200

for acesulfame K (Table 8.9).

The ADI value stipulated for the potassium salt of

acesulfame is 0–9 mg/kg of body weight.

(8.15)

Oxathiazinone dioxides are obtained from fluo-

rosulfonyl isocyanate and alkynes, or from com-

Table 8.9.Sweetness of some oxathiazinone dioxides

(Na-salts) (Formula 8.15)

R^1 R^2 fsac, g R^1 R^2 fsac, g

HH 10EtH 20

H Me 130 a Et Me 250

Me H 20 Pr Me 30

Me Me 130 i-Pr Me 50

H Et 150

aAcesulfame.