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


    CITRIC ACID AND FATTY ACID ESTERS OF GLYCEROL

    Synonyms                     Citrated mono- and diglycerides; Citric
                                 acid esters of mono- and diglycerides

    Definition                   Citrated mono- and diglycerides are
                                 formed by esterifying the hydroxyl
                                 groups of mono- and diglycerides.

    Uses                         As emulsifier.

    Biological Data

    Biochemical aspects

         In vitro hydrolysis by pancreatic lipase and liver esterase
    produced nearly the same yield of citric acid in the same 2-hour
    period as spontaneous hydrolysis at pH 7.5-8.5 (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 per cent.;
    and or lard, 16.7 and 35.5 per cent. These were calculated to give
    isocaloric diets at 2 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 per
    cent. that of lard (Huntingdon, 1966).

         In 2 groups of 5 male and 5 female weanling rats fed diets
    containing 0 and 20 per cent. of ester for 7 days, food intake and
    body-weight maintenance were the same in both groups, and the
    digestibility of the ester was calculated to be 99 per cent. (Rosner,
    1959).

    Acute toxicity

         No data 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 per cent levels (Huntingdon, 1966).

    Long-term studies

    No data are available.

    Comments

         This substance is hydrolysed 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

         See mixed tartaric and acetic and fatty acid esters of glycerol
    (p. 96)

    REFERENCES

    Huntingdon Research Centre (1966) Unpublished report submitted by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

    Lang, K. (1963) 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
    

    See Also:
       Toxicological Abbreviations