Toxicological evaluation of some food
    additives including anticaking agents,
    antimicrobials, antioxidants, emulsifiers
    and thickening agents



    WHO FOOD ADDITIVES SERIES NO. 5







    The evaluations contained in this publication
    were prepared by the Joint FAO/WHO Expert
    Committee on Food Additives which met in Geneva,
    25 June - 4 July 19731

    World Health Organization
    Geneva
    1974

              

    1    Seventeenth Report of the Joint FAO/WHO Expert Committee on
    Food Additives, Wld Hlth Org. techn. Rep. Ser., 1974, No. 539;
    FAO Nutrition Meetings Report Series, 1974, No. 53.


    CITRIC AND FATTY ACID ESTERS OF GLYCEROL

    Explanation

         These emulsifiers have been evaluated for acceptable daily intake
    by the Joint FAO/WHO Expert Committee on Food Additives (see Annex 1,
    Ref. No. 13) in 1966.

         The previously published monograph has been revised and is
    reproduced in its entirety below.

    BIOLOGICAL DATA

    BIOCHEMICAL ASPECTS

         In vitro hydrolysis by pancreatic lipase and liver esterase
    produced nearly the same yield of citric acid in the same two-hour
    period as spontaneous hydrolysis at pH 7.5 to 8.5 (Lang, 1964). The
    existence of a true citric acid ester bond in this compound has been
    questioned (Schade, 1963).

         The digestibility of this compound was compared with a physical
    mixture of its constituents and with lard in groups of 20 male and
    female rats on a calorie-restricted basal diet, for 10 days. The
    dietary levels of the ester and mixture were 23.1 and 37.5%; and of
    lard, 16.7 and 35.5%. These were calculated to give isocaloric diets
    at two levels of caloric supplementation above the control level.
    Faecal fat estimation and body fatty acid distribution showed that the
    ester was completely digestible, although the absorption of the ester
    or its component mixture was about 50% that of lard (Huntingdon,
    1966).

         In two groups of five male and five female weanling rats fed
    diets containing 0 and 20% of ester for seven days, food intake and
    body weight maintenance were the same in both groups, and the
    digestibility of the ester was calculated to be 99% (Rosner, 1959).

    TOXICOLOGICAL STUDIES

    Acute toxicity

         No data are available.

    Short-term studies

         In the 10-day study quoted above (under Biochemical aspects),
    gross and microscopic examination of major organs of the test animals
    revealed only dystrophic lower-nephron calcification in animals
    receiving the highest levels of the ester or the component mixture. No
    effect was seen at the 23.1% levels (Huntingdon, 1966).

    Long-term studies

         No data are available.

    Comments:

         This substance is hydrolyzed completely in the intestinal tract
    into components which are normal constituents of the diet. Evaluation
    is based on knowledge of the metabolic fate and lack of toxicity of
    the constituent citric acid and fatty acid esters of glycerol.

    EVALUATION

    Estimate of acceptable daily intake for man

         Not limited.*1,2

    REFERENCES

    Huntingdon Research Centre (1966) Unpublished report submitted by
         Emulsion A/S

    Lang, K. (1964) Unpublished report submitted by Emulsion A/S

    Rosner, L. (1959) Unpublished report by Laboratory of Vitamin
         Technology

    Schade, H. (1963) Unpublished report submitted by Emulsion A/S

              

    *1    See relevant paragraph in the seventeenth report (pages 10-11).

    *2    As sum of glycerol esters of fatty acids and acetic, citric,
    lactic and tartaric acids, provided that the total food additive
    intake of tartaric acid does not exceed 30 mg/kg.

    See Also:
       Toxicological Abbreviations
       CITRIC AND FATTY ACID ESTERS OF GLYCEROL (JECFA Evaluation)