(a) Lactose is the carbohydrate normally obtained from whey. It may be anhydrous or contain one molecule of water of crystallization or be a mixture of both forms.
(b) The food shall meet the following specifications:
(1) The lactose content is not less than 98.0 percent, mass over mass (m/m), calculated on a dry basis.
(2) The sulfated ash content is not more than 0.3 percent, m/m, calculated on a dry basis.
(3) The pH of a 10.0-percent m/m solution is not less than 4.5 nor more than 7.5.
(4) The loss on drying for 16 hours at 120 °C is not more than 6.0 percent, m/m.
(c) The name of the food is “Lactose” or, alternatively, “Milk sugar”.
(d) The methods of analysis in paragraphs (d)(1), (d)(2), (d)(3), (d)(4), and (d)(5) of this section are to be used to determine whether the food meets the requirements of paragraphs (b)(1), (b)(2), (b)(3), and (b)(4) of this section. The methods are contained in “Official Methods of Analysis of the Association of Official Analytical Chemists”, 14th Ed. (1984), including the 4th Supp. (1988), which is incorporated by reference in accordance with 5 U.S.C. 552(a). Copies of the material incorporated by reference may be obtained from the AOAC INTERNATIONAL, 481 North Frederick Ave., suite 500, Gaithersburg, MD 20877, or may be examined 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.
(1) Lactose content, sections 31.064 to 31.071, “Purity of Lactose, Liquid Chromatographic Method,” First Action, 14th Ed. (1984), pp. 583 and 584.
(2) Lactose content, sections 31.064 to 31.071, “Purity of Lactose, Liquid Chromatographic Method,” “Changes in Official Methods of Analysis,” 14th Ed., 4th Supp. (1988), p. 212. This reference recognizes the change in status of the method from first action to final action.
(3) Sulfated ash content, section 31.014, “Ash of Sugars and Sirups,” Final Action, Sulfated Ash, 14th Ed. (1984), p. 575.
(4) pH, section 14.022, “pH of Flour, Potentiometric Method,” Final Action, except that a 10-percent m/m solution of lactose in water is used for the determination, 14th Ed. (1984), p. 252.