[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of April 1, 2006]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR172.133]
[Page 34-35]
TITLE 21--FOOD AND DRUGS
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN
SERVICES (CONTINUED)
PART 172_FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN
CONSUMPTION--Table of Contents
Subpart B_Food Preservatives
Sec. 172.133 Dimethyl dicarbonate.
Dimethyl dicarbonate (CAS Reg. No. 4525-33-1) may be safely used in
food in accordance with the following prescribed conditions:
(a) The additive meets the following specifications:
(1) The additive has a purity of not less than 99.8 percent as
determined by the following titration method:
principles of method
Dimethyl dicarbonate (DMDC) is mixed with excess diisobutylamine
with which it reacts quantitatively. The excess amine is backtitrated
with acid.
apparatus
250-milliliter (mL) Beaker
100-mL Graduate cylinder
25-mL Pipette
10-mL Burette (automatic, eg., Metrohm burette)
Stirrer
Device for potentiometric titration
Reference electrode
Glass electrode
reagents
Acetone, analytical-grade
Solution of 1 N diisobutylamine in chlorobenzene, distilled
1 N Acetic Acid
procedure
Accurately weigh in about 2 grams of the sample (W) and dissolve in
100 mL acetone. Add accurately 25 mL of the 1 N diisobutylamine solution
by pipette and allow to stand for 5 minutes. Subsequently, titrate the
reaction mixture potentiometrically with 1 N hydrochloric acid
(consumption=a mL) while
[[Page 35]]
stirring. For determining the blank consumption, carry out the analysis
without a sample (consumption=b mL).
calculation
[GRAPHIC] [TIFF OMITTED] TR10MR99.023
Note: For adding the diisobutylamine solution, always use the same
pipette and wait for a further three drops to fall when the flow has
stopped.
(2) The additive contains not more than 2,000 ppm (0.2 percent)
dimethyl carbonate as determined by a method entitled ``Gas
Chromatography Method for Dimethyl Carbonate Impurity in Dimethyl
Dicarbonate,'' which is incorporated by reference in accordance with 5
U.S.C. 552(a). Copies are available from the Center for Food Safety and
Applied Nutrition (HFS-200), 5100 Paint Branch Pkwy., College Park, MD
20740, or at the National Archives and Records Administration (NARA).
For information on the availability of this material at NARA, call 202-
741-6030, or go to: http://www.archives.gov/federal--register/code--of--
federal--regulations/ibr--locations.html.
(b) The additive is used or intended for use as a microbial control
agent in the following beverages under normal circumstances of bottling,
canning, or other forms of final packaging, where the viable microbial
load has been reduced to 500 microorganisms per milliliter or less by
current good manufacturing practices such as heat treatment, filtration,
or other technologies prior to the use of dimethyl dicarbonate:
(1) In wine, dealcoholized wine, and low alcohol wine in an amount
not to exceed 200 parts per million.
(2) In ready-to-drink teas in an amount not to exceed 250 parts per
million.
(3) In carbonated or noncarbonated, nonjuice-containing (less than
or equal to 1 percent juice), flavored or unflavored beverages
containing added electrolytes (5-20 milliequivalents/liter sodium ion
(Na+) and 3-7 milliequivalents/liter potassium ion (K+)) in an amount
not to exceed 250 parts per million.
(4) In carbonated, dilute beverages containing juice, fruit flavor,
or both, with juice content not to exceed 50 percent, in an amount not
to exceed 250 parts per million.
(c) To ensure the safe use of the food additive, the label of the
package containing the additive shall bear, in addition to other
information required by the Federal Food, Drug, and Cosmetic Act:
(1) The name of the additive ``dimethyl dicarbonate.''
(2) The intended use of the additive.
(3) Adequate directions for use to ensure compliance with this
section.
[53 FR 41329, Oct. 21, 1988, as amended at 58 FR 6091, Jan. 26, 1993; 59
FR 5319, Feb. 4, 1994; 61 FR 14245, Apr. 1, 1996; 61 FR 26788, May 29,
1996; 66 FR 13653, Mar. 7, 2001]
Additives that reference this regulation: |
