Problems in evaluating the safety of enzymes in food processing
    were discussed at the fifteenth, eighteenth and twenty-ninth meetings
    of the Expert Committee, when principles relating to their evaluation
    were elaborated (Annex 1, references 26, 35, and 70). At its present
    meeting, the Committee reaffirmed those principles, which have been
    consolidated in Annex III of "Principles for the Safety Assessment of
    Food Additives and Contaminants in Food" (Annex 1, reference 76).

         For the purpose of toxicological evaluation, the enzyme
    preparations under present consideration were grouped into the
    following classes:

    - Class III -  Enzymes derived from Aspergillus oryzae;

    - Class IV -   Enzymes derived from Aspergillus niger; and

    - Class V -    Enzymes derived from Trichoderma reesei, Trichoderma
                   harzianum, Penicillium funiculosum, Aspergillus

         The guidelines established by JECFA for these classes of enzymes
    provide a basis for the toxicological studies required for their

         At the twenty-ninth meeting the Committee concluded that, when
    enzyme preparations from either class IV or class V are added directly
    to food but not subsequently removed, an acceptable daily intake
    should be established to ensure that levels of the enzyme preparations
    in food are safe. In order to evaluate the information received on the
    estimate of the amount of enzyme preparations used in the
    toxicological studies and levels of consumption resulting from their
    use in food, the Committee adopted the concept of enzyme total organic
    solids (TOS), which is defined as follows; % TOS = 100-(A+W+D), where
    A = Z ash, W = % water, and D = % diluent and carrier (Ad hoc
    Enzyme Technical Committee, 1981; Pariza & Foster, 1983). This concept
    overcomes the problem that enzyme preparations of different activities
    and forms were used in the toxicological studies. It also takes into
    account that most of the organic solids in this fraction are not the
    enzyme per se.

         In establishing acceptable daily intakes for the enzymes in
    classes IV and V, the Committee noted that the animal feeding studies
    were primarily of short-term duration. It, therefore, concluded that
    it would be appropriate to use a safety factor greater that the usual


    Ad hoc Enzyme Technical Committee 41981). The 1978 enzyme survey,
    summarized data, National Academy of Sciences/National Research
    Council/Food and Nutrition Board, Committee on GRAS List Survey,
    Phase III, National Academy Press, Washington, D.C.

    Pariza, M.W. & Foster, E.M. 41983). Determining the Safety of Enzymes
    used in Food Processing, J. Food Protection, 46: 453-468.

    See Also:
       Toxicological Abbreviations