FAO Nutrition Meetings
Report Series No. 40A,B,C
WHO/Food Add./67.29
TOXICOLOGICAL EVALUATION OF SOME
ANTIMICROBIALS, ANTIOXIDANTS, EMULSIFIERS,
STABILIZERS, FLOUR-TREATMENT AGENTS, ACIDS AND BASES
The content of this document is the result of the deliberations of the
Joint FAO/WHO Expert Committee on Food Additives which met at Rome,
13-20 December, 19651 Geneva, 11-18 October, 19662
1 Ninth Report of the Joint FAO/WHO Expert Committee on Food
Additives, FAO Nutrition Meetings Report Series, 1966 No. 40;
Wld Hlth Org. techn. Rep. Ser., 1966, 339
2 Tenth Report of the Joint FAO/WHO Expert Committee on Food
Additives, FAO Nutrition Meetings Report Series, 1967, in press;
Food and Agriculture Organization of the United Nations
World Health Organization
1967
DIACETYLTARTARIC ACID AND FATTY ACID ESTERS OF GLYCEROL
Synonyms Diacetyl tartaric acid esters of mono- and
diglycerides; Tartaric acid esters,
diacetylated, of mono- and diglycerides
Chemical description This product consists of mixed glycerol esters
of fatty acids and diacetyl tartaric acid.
Structural formula Major components are:
I. CH2-OR
CH-OCO-CH(OCO-CH3)-CH(OCO-CH3)-COOH
CH2-OCO-CH(OCO-CH3)-CH(OCO-CH3)-COOH
II. CH2-OR
'
CH-OR
'
CH2-OCO-CH(OCO-CH3)-CH(OCO-CH3)-COOH
III. CH2-OR
'
CH-OCO-CH(OCO-CH3)-CH(OCO-CH3)-COOH
'
CH2-OR
where R represents various saturated and
unsaturated fatty acid moiety or hydrogen in
II or III.
Definition The product consists of esters made by the
interaction of diacetyl tartaric anhydride
with monoglycerides, or with mono-diglyceride
mixture made from edible oils, fats or fatty
acids therefrom. The material appearing in
commerce often consists of mixtures of the
product described above with mono-and
diglycerides.
Description The esters range in appearance from sticky,
viscous liquids through a fat-like consistency
to yellow waxes which hydrolyse in moist air
to liberate acetic acid.
Uses As emulsifier.
Biological Data
Biochemical aspects
Six male rats ware fed 0.53-0.81 g/kg body-weight
14C-acetyltartaric acid ester of none-and diglycerides (labelled in
the two carboxyl groups of tartaric acid) as an oily solution. Within
24 hours only 26-31 per cent. of the radioactivity was absorbed.
Twelve to twenty per cent. of the radioactivity was eliminated as
14CO2 and 8-13 per cent. was excreted in the urine; 2 per cent. was
found in the carcass (Lang & Schmidt, 1965). The analysis of the depot
fat of dogs fed up to 20 per cent. of the substance for 22 months
showed no traces or either free or a fat soluble derivative of
tartaric acid (Koppanyi & Dardin, 1950). The digestibility coefficient
was over 90 per cent. of the substance or about the same as that of
lard (Koppanyi & Dardin, 1950). In an aqueous medium diacetyl tartaric
ester of mono- and diglycerides was hydrolysed spontaneously to mono-
and diglycerides and acetylated tartaric acid, the hydrolysis being
somewhat accelerated by pancreatic lipase (Lang & Schmidt, 1965).
There was some evidence that diacetyltartaric acid was also hydrolysed
in the body (Sourkes & Koppanyi, 1950).
Acute toxicity
No acute toxic effects at a practicable dose level have been
demonstrated. Rats and rabbits tolerated intragastric doses of 30 g/kg
body-weight and dogs 27 g/kg body-weight without any adverse effects.
No diarrhoea was noted and autopsied animals showed no pathological
changes. Histological examination of liver and kidneys of animals
killed 10 days after the administration of the substance showed no
abnormalities (Koppanyi & Dardin, 1950).
Short-term studies
Dog. Thirteen dogs each received daily i.v. injections of 0.5
per cent. suspensions of the substance in isotonic glucose at a dose
rate of 40-50 ml/kg body-weight for a total of up to 30 infusions. A
fall in haemoglobin concentration occurred in 11 dogs and a pleural
effusion in 6. Groups of 2 three-year old dogs were fed diets
containing 0, 5, 10 and 20 per cent. of diacetyl tartaric esters of
mono- and diglycerides for 25-1/2 months. No specific effects
attributable to the test substance were seen (Hartwig et al., 1962).
Long-term studies
Rat. Groups of 8 rats were fed 0, 5, 10 and 20 per cent.
diacetyltartaric esters of mono- and diglycerides, another 2 groups
were fed 50 per cent. white bread (broad control group) and 50 per
cent. bread which was baked with the addition or 10 per cent. of the
emulsifier in terms of flour weight (bread test group) for two years.
No difference was found between the groups regarding body-weight,
external appearance, liver and kidney weights and mortality rate.
Autopsies and histological examination of the major organs showed no
changes attributable to the test substance. A second generation was
maintained on similar regimes for 22 months. There was no difference
between the groups regarding body-weight, mortality and results of
gross and histological examination. All litters were normal (Koppanyi
& Dardin, 1950).
Comments
Diacetyltartaric acid is not a natural consistuent of the diet,
and its rate of spontaneous hydrolysis possibly allows the absorption
of some unhydrolyzed compound. The experimental results show that the
ester has a very low toxicity when given orally and that the
acetylated tartaric acid moiety is absorbed only to a small extent.
Evaluation is based on the available toxicological information rather
than the results of the biochemical and metabolic studies.
Evaluation
Level causing no toxicological effect
Rat. 100 000 ppm in the diet, equivalent to 5000 mg/kg
body-weight/day.
Estimate of acceptable daily intakes for man
mg/kg body-weight
Unconditional acceptance1 0-25
Conditional acceptance 25-50
REFERENCES
FAO/WHO (1965) FAO Nutrition Meetings Report Series No. 38;
Wld Hlth Org. techn. Rep. Ser., 309
Hartwig, Q. L., Singleton, W. S. & Cotlar, A. M. (1962) Toxicol.
Appl. Pharmacol., 4, 107
Koppanyi, T. &, Dardin, V. (1950) Unpublished report to WHO
Lang, K. & Schmidt, B. (1967) In press
Sourkes, T, L. & Koppanyi, T. (1950) J. Amer. Pharm. Assoc., sci.
Ed., 39, 275
1 The total food additive intake of tartaric acid should not exceed
6-20 mg/kg body-weight/day (FAO/WHO, 1965).