§ 172.665 Gellan gum.
The food additive gellan gum may be safely used in food in accordance with the following prescribed conditions:
（a） The additive is a high molecular weight polysaccharide gum produced from Pseudomonas elodea by a pure culture fermentation process and purified by recovery with isopropyl alcohol. It is composed of tetrasaccharide repeat units, each containing one molecule of rhamnose and glucuronic acid, and two molecules of glucose. The glucuronic acid is neutralized to a mixed potassium, sodium, calcium, and magnesium salt. The polysaccharide may contain acyl （glyceryl and acetyl） groups as the O-glycosidically linked esters.
（b） The strain of P. elodea is nonpathogenic and nontoxic in man and animals.
（c） The additive is produced by a process that renders it free of viable cells of P. elodea .
（d） The additive meets the following specifications:
（1） Positive for gellan gum when subjected to the following identification tests:
（i） A 1-percent solution is made by hydrating 1 gram of gellan gum in 99 milliliters of distilled water. The mixture is stirred for about 2 hours, using a motorized stirrer and a propeller-type stirring blade. A small amount of the above solution is drawn into a wide bore pipet and transferred into a solution of 10-percent calcium chloride. A tough worm-like gel will form instantly.
（ii） To the 1-percent distilled water solution prepared for identification test （i）, 0.50 gram of sodium chloride is added. The solution is heated to 80 °C with stirring, held at 80 °C for 1 minute, and allowed to cool to room temperature without stirring. A firm gel will form.
（2） Residual isopropyl alcohol （IPA） not to exceed 0.075 percent as determined by the procedure described in the Xanthan Gum monograph, the “Food Chemicals Codex,” 4th ed. （1996）, pp. 437–438, which is incorporated by reference in accordance with 5 U.S.C. 552（a） and 1 CFR part 51. Copies are available from the National Academy Press, Box 285, 2101 Constitution Ave. NW., Washington, DC 20055 （Internet address http://www.nap.edu ）, or may be examined at the Center for Food Safety and Applied Nutrition's Library, Food and Drug Administration, 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.
（e） The additive is used or intended for use in accordance with current good manufacturing practice as a stabilizer and thickener as defined in §170.3（o）（28） of this chapter. The additive may be used in foods where standards of identity established under section 401 of the Federal Food, Drug, and Cosmetic Act do not preclude such use.
（f） To assure safe use of the additive:
（1） The label of its container shall bear, in addition to other information required by the Federal Food, Drug, and Cosmetic Act, the name of the additive and the designation “food grade”。
（2） The label or labeling of the food additive container shall bear adequate directions for use.
[55 FR 39614, Sept. 28, 1990, as amended at 57 FR 55445, Nov. 25, 1992; 64 FR 1758, Jan. 12, 1999]
更多关于美国 FDA 已批准的直接用于人类食品的添加剂种类法规，请点击美国FDA 21 CFR 第172部分已批准的直接用于人类食品的添加剂种类汇总
