[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of April 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR173.357]

[Page 139]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                          SERVICES (CONTINUED)
 
PART 173--SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION--Table of Contents
 
                   Subpart D--Specific Usage Additives
 
Sec. 173.357  Materials used as fixing agents in the immobilization of enzyme preparations.

    Fixing agents may be safely used in the immobilization of enzyme 
preparations in accordance with the following conditions:
    (a) The materials consist of one or more of the following:
    (1) Substances generally recognized as safe in food.
    (2) Substances identified in this subparagraph and subject to such 
limitations as are provided:

------------------------------------------------------------------------
              Substances                          Limitations
------------------------------------------------------------------------
Cellulose triacetate.................  May be used as a fixing material
                                        in the immobilization of lactase
                                        for use in reducing the lactose
                                        content of milk.
Diethylaminoethyl-cellulose..........  May be used as a fixing material
                                        in the immobilization of glucose
                                        isomerase enzyme preparations
                                        for use in the manufacture of
                                        high fructose corn syrup, in
                                        accordance with Sec.  184.1372
                                        of this chapter.
Glutaraldehyde.......................   Do.
Periodic acid (CAS Reg. No. 10450-60-
 9)..
Polyethylenimine reaction product      May be used as a fixing material
 with 1,2-dichloroethane (CAS Reg.No.   in the immobilization of
 68130-97-2) is the reaction product    glucoamylase enzyme preparations
 of homopolymerization of               from Aspergillus niger for use
 ethylenimine in aqueous hydrochloric   in the manufacture of beer.
 acid at 100 C and of cross-linking    May be used as a fixing material
 with 1,2-dichloroethane. The           in the immobilization of:
 finished polymer has an average       1. Glucose isomerase enzyme
 molecular weight of 50,000 to 70,000   preparations for use in the
 as determined by gel permeation        manufacture of high fructose
 chromatography. The analytical         corn syrup, in accordance with
 method is entitled ``Methodology for   Sec.  184.1372 of this chapter.
 Molecular Weight Detection of         2. Glucoamylase enzyme
 Polyethylenimine,'' which is           preparations from Aspergillus
 incorporated by reference in           niger for use in the manufacture
 accordance with 5 U.S.C. 552(a) and    of beer. Residual ethylenimine
 1 CFR part 51. Copies may be           in the finished polyethylenimine
 obtained from the Division of          polymer will be less than 1 part
 Petition Control, Center for Food      per million as determined by gas
 Safety and Applied Nutrition (HFS-     chromatography-mass
 200), 5100 Paint Branch Pkwy.,         spectrometry. The residual
 College Park, MD 20740, and may be     ethylenimine is determined by an
 examined at the Center for Food        analytical method entitled
 Safety and Applied Nutrition's         ``Methodology for Ethylenimine
 Library, 200 C St. SW., Washington,    Detection in Polyethylenimine,''
 DC, or at the Office of the Federal    which is incorporated by
 Register, 800 North Capitol St. NW.,   reference in accordance with 5
 suite 700, Washington, DC.             U.S.C. 552(a) and 1 CFR part 51.
                                        Residual 1,2-dichloroethane in
                                        the finished polyethylenimine
                                        polymer will be less than 1 part
                                        per million as determined by gas
                                        chromatography. The residual 1,2-
                                        dichloroethane is determined by
                                        an analytical method entitled,
                                        ``Methodology for
                                        Ethylenedichloride Detection in
                                        Polyethylenimine,'' which is
                                        incorporated by reference in
                                        accordance with 5 U.S.C. 552(a)
                                        and 1 CFR part 51. Copies may be
                                        obtained from the Division of
                                        Petition Control, Center for
                                        Food Safety and Applied
                                        Nutrition (HFS-215), 5100 Paint
                                        Branch Pkwy., College Park, MD
                                        20740, or may be examined at the
                                        Center for Food Safety and
                                        Applied Nutrition's Library, 200
                                        C St. SW., Washington, DC, or
                                        the Office of the Federal
                                        Register, 800 North Capitol St.
                                        NW., suite 700, Washington, DC.
------------------------------------------------------------------------

    (b) The fixed enzyme preparation is washed to remove residues of the 
fixing materials.

[48 FR 5716, Feb. 8, 1983, as amended at 52 FR 39512, Oct. 22, 1987; 55 
FR 12172, Apr. 2, 1990; 59 FR 36937, July 20, 1994; 61 FR 4873, Feb. 9, 
1996; 61 FR 14245, Apr. 1, 1996]