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.

    ACETYLATED DISTARCH GLYCEROL

    Explanation

         Modification is carried out with epichlorhydrin to a maximum of
    0.3% and acetic anhydride to a maximum of 8%. The amount of acetyl
    groups introduced does not exceed 2.5%. Further treatment, such as
    bleaching is often carried out.

    BIOLOGICAL DATA

    BIOCHEMICAL ASPECTS

         The in vitro digestibility of acetylated distarch glycerol
    (0.3 per epichlorhydrin, 1.2 or 2.5% acetyl content) varies with the
    acetyl content but is not affected by cross-linkage. At 1.2%
    acetylation some 82% of the modified starch are digestible, at 2.5%
    only 68.5% are hydrolyzed enzymatically (Kruger, 1970). The caloric
    value was determined by reference to a dose-response curve established
    in groups of 10 male rats given a basic diet with graded supplements
    of 0, 0.75 g, 1.5 g, 3.0 g and 4.5 g sucrose equivalent to 0, 3, 6, 12
    and 18 calories per day. Starches modified by the use of 0.1%
    epichlorhydrin + 5.5% acetic anhydride and 0.3% epichlorhydrin + 5.5%
    acetic anhydride were tested against native starch at levels of
    supplementation of 1.5 g and 3.0 g per day for 28 days. Weight gain on
    modified starch supplement was slightly reduced compared with than on
    unmodified starch. All rats remained normally active and healthy. The
    caloric estimates were similar for both levels of epichlorhydrin
    treatment (Oser, 1961).

    TOXICOLOGICAL STUDIES

    Short-term studies

    Rat

         Groups of 15 male and 15 female rats were fed for 90 days on
    diets containing 50% either native or modified starch (0.3%
    epichlorhydrin + 10.5% acetic anhydride). The growth rate of male rats
    was significantly lower compared with controls on unmodified starch.
    The full and empty caecal weights of both male and female rats in the
    test groups were significantly greater than in controls. Haematology,
    blood chemistry, urinalysis, organ weights and gross as well as
    histological examination were normal (Oser, 1964).

    Comments:

         The feeding studies with rats show that the modified starch is
    well utilized. The available evidence for the group of modified
    starches considered suggest that caecal enlargement without associated
    histopathological changes is without toxicological significance. The
    short-term rat study shows no other significant effects related to
    treatment, the observed growth depression being the obvious result of
    the high dietary level used. No long-term study is available but the
    collateral evidence from starch acetate and distarch glycerol
    indicates that neither of these modifications singly applied cause any
    adverse effects.

    EVALUATION

    Estimate of acceptable daily intake for man

         Not limited.*

    REFERENCES

    Kruger, L. (1970) Unpublished reports Nos 405 and 406 submitted by
         National Starch and Chemical Corporation

    Oser, M. (1961) Unpublished report of Food and Drug Research
         Laboratories Inc. No. 81774, submitted by National Starch and
         Chemical Corporation

    Oser, B. L. (1964) Unpublished report of Food and Drug Research
         Laboratories Inc. No. 85554, submitted by National Starch and
         Chemical Corporation

              

    *    See relevant paragraph in the seventeenth report, pages 10-11.

    See Also:
       Toxicological Abbreviations
       Acetylated distarch glycerol  (FAO Nutrition Meetings Report Series 46a)
       Acetylated distarch glycerol (WHO Food Additives Series 1)
       Acetylated distarch glycerol (WHO Food Additives Series 17)
       ACETYLATED DISTARCH GLYCEROL (JECFA Evaluation)