Source: https://www.govregs.com/regulations/21/173.25
Timestamp: 2019-10-24 03:56:11
Document Index: 154714350

Matched Legal Cases: ['§ 173', 'art 173', '§ 173', '§ 173', '§ 173', '§ 176', '§ 176', '§ 176', '§ 173', 'art 51']

21 CFR 173.25 - Ion-exchange resins. § 173.25 - Ion-exchange resins.
All TitlesTitle 21Chapter IPart 173Subpart A - Polymer Substances and Polymer Adjuvants for Food Treatment
View all text of Subpart A [§ 173.5 - § 173.75]
§ 173.25 - Ion-exchange resins.
(2) Sulfonated anthracite coal meeting the requirements of ASTM method D388-38, Class I, Group 2, “Standard Specifications for Classification of Coal by Rank,” which is incorporated by reference. Copies are available from University Microfilms International, 300 N. Zeeb Rd., Ann Arbor, MI 48106, or available for inspection 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.
(iii) The temperature of the water passing through the resin beds identified in paragraphs (b)(1) (i) and (ii) of this section is maintained at 30 °C or less, and the flow rate of the water passing through the beds is not less than 2 gallons per cubic foot per minute.
(2) The ion-exchange resins identified in paragraphs (a) (13) and (16) of this section are used to treat water and aqueous food only of the types identified under Categories I, II, and VI-B in table 1 of § 176.170(c) of this chapter: Provided, That the temperature of the water or food passing through the resin beds is maintained at 50 °C or less and the flow rate of the water or food passing through the beds is not less than 0.5 gallon per cubic foot per minute.
(i) The ion-exchange resin identified in paragraph (a)(13) of this section is used to treat water and aqueous food only of the types identified under categories I, II, and VI-B in Table 1 of § 176.170(c) of this chapter: Provided, That the temperature of the water or food passing through the resin bed is maintained at 50 °C or less and the flow rate of the water or food passing through the bed is not less than 0.5 gallon per cubic foot per minute.
(ii) The ion-exchange resin identified in paragraph (a)(16) of this section is used to treat water and aqueous food only of the types identified under categories I, II, and VI-B in Table 1 of § 176.170(c) of this chapter, Provided, that either:
(A) The temperature of the water or food passing through the resin bed is maintained at 50 °C or less and the flow rate of the water or food passing through the bed is not less than 0.5 gallon per cubic foot per minute; or
(B) Extracts of the resin will be found to contain no more than 1 milligram/kilogram dimethylaminopropylamine in each of the food simulants, distilled water and 10 percent ethanol, when, following washing and pretreatment of the resin in accordance with § 173.25(c)(1), the resin is subjected to the following test under conditions simulating the actual temperature and flow rate of use: “The Determination of 3-Dimethylaminopropylamine in Food Simulating Extracts of Ion Exchange Resins,” February 4, 1998, which is incorporated by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies are available from the Office of Food Additive Safety (HFS-200), Center for Food Safety and Applied Nutrition, Food and Drug Administration, 5001 Campus Dr., College Park, MD 20740, 240-402-1200, or may be examined at the Food and Drug Administration's Main Library, 10903 New Hampshire Ave., Bldg. 2, Third Floor, Silver Spring, MD 20993, 301-796-2039, 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.
(3) The ion-exchange resin identified in paragraph (a)(17) of this section is used only for industrial application to treat bulk quantities of aqueous food, including potable water, or for treatment of municipal water supplies, subject to the condition that the temperature of the food or water passing through the resin bed is maintained at 25 °C or less and the flow rate of the food or water passing through the bed is not less than 2 gallons per cubic foot per minute.
(4) The ion-exchange resin identified in paragraph (a)(18) of this section is used to treat aqueous sugar solutions subject to the condition that the temperature of the sugar solution passing through the resin bed is maintained at 82 °C (179.6 °F) or less and the flow rate of the sugar solution passing through the bed is not less than 46.8 liters per cubic meter (0.35 gallon per cubic foot) of resin bed volume per minute.
(i) For resins that comply with the requirements in paragraph (d)(2)(i) of this section, the pH range for the resin shall be no less than 3.5 and no more than 9, and the temperatures of water and food passing through the resin bed shall not exceed 25 °C.
(ii) For resins that comply with the requirements in paragraph (d)(2)(ii) of this section, the pH range for the resin shall be no less than 2 and no more than 10, and the temperatures of water and food passing through the resin shall not exceed 50 °C.
(4) Found to result in no more than 1 part per million of organic extractives obtained with each of the named solvents, distilled water, 15 percent alcohol, and 5 percent acetic acid when, having been washed and otherwise treated in accordance with the manufacturer's directions for preparing them for use with food, the ion-exchange resin is subjected to the following test: Using a separate ion-exchange column for each solvent, prepare columns using 50 milliliters of the ready to use ion-exchange resin that is to be tested. While maintaining the highest temperature that will be encountered in use pass through these beds at the rate of 350-450 milliliters per hour the three test solvents distilled water, 15 percent (by volume) ethyl alcohol, and 5 percent (by weight) acetic acid. The first liter of effluent from each solvent is discarded, then the next 2 liters are used to determine organic extractives. The 2-liter sample is carefully evaporated to constant weight at 105 °C; this is total extractives. This residue is fired in a muffle furnace at 850 °C to constant weight; this is ash. Total extractives, minus ash equals the organic extractives. If the organic extractives are greater than 1 part per million of the solvent used, a blank should be run on the solvent and a correction should be made by subtracting the total extractives obtained with the blank from the total extractives obtained in the resin test. The solvents used are to be made as follows:
Distilled water (de-ionized water is distilled). 15 percent ethyl alcohol made by mixing 15 volumes of absolute ethyl alcohol A.C.S. reagent grade, with 85 volumes of distilled de-ionized water. 5 percent acetic acid made by mixing 5 parts by weight of A.C.S. reagent grade glacial acetic acid with 95 parts by weight of distilled de-ionized water. In addition to the organic extractives limitation prescribed in this paragraph, the ion-exchange resin identified in paragraph (a)(17) of this section, when extracted with each of the named solvents, distilled water, 50 percent alcohol, and 5 percent acetic acid, will be found to result in not more than 7 parts per million of nitrogen extractives (calculated as nitrogen) when the resin in the free-base form is subjected to the following test immediately before each use: Using a separate 1-inch diameter glass ion-exchange column for each solvent, prepare each column using 100 milliliters of ready to use ion-exchange resin that is to be tested. With the bottom outlet closed, fill each ion-exchange column with one of the three solvents at a temperature of 25 °C until the solvent level is even with the top of the resin bed. Seal each column at the top and bottom and store in a vertical position at a temperature of 25 °C. After 96 hours, open the top of each column, drain the solvent into a collection vessel, and analyze each drained solvent and a solvent blank for nitrogen by a standard micro-Kjeldahl method.