21 C.F.R. § 173.310
Current through September 30, 2024
Boiler water additives may be safely used in the preparation of steam that will contact food, under the following conditions:
| Substances | Limitations |
| Acrylamide-sodium acrylate resin | Contains not more than 0.05 percent by weight of acrylamide monomer. |
| Acrylic acid/2-acrylamido-2-methyl propane sulfonic acid copolymer having a minimum weight average molecular weight of 9,900 and a minimum number average molecular weight of 5,700 as determined by a method entitled "Determination of Weight Average and Number Average Molecular Weight of 60/40 AA/AMPS" | Total not to exceed 20 parts per million (active) in boiler feedwater. |
| Ammonium alginate | |
| Cobalt sulfate (as catalyst) | |
| 1-hydroxyethylidene-1,1-diphosphonic acid (CAS Reg. No. 2809-21-4) and its sodium and potassium salts | |
| Lignosulfonic acid | |
| Monobutyl ethers of polyethylene-polypropylene glycol produced by random condensation of a 1:1 mixture by weight of ethylene oxide and propylene oxide with butanol | Minimum mol. wt. 1,500. |
| Poly(acrylic acid-co-hypophosphite), sodium salt (CAS Reg. No. 71050-62-9), produced from a 4:1 to a 16:1 mixture by weight of acrylic acid and sodium hypophosphite | Total not to exceed 1.5 parts per million in boiler feed water. Copolymer contains not more than 0.5 percent by weight of acrylic acid monomer (dry weight basis). |
| Polyethylene glycol | As defined in § 172.820 of this chapter. |
| Polymaleic acid [CAS Reg. No. 26099-09-2], and/or its sodium salt. [CAS Reg. No. 30915-61-8 or CAS Reg. No. 70247-90-4] | Total not to exceed 1 part per million in boiler feed water (calculated as the acid). |
| Polyoxypropylene glycol | Minimum mol. wt. 1,000. |
| Potassium carbonate | |
| Potassium tripolyphosphate | |
| Sodium acetate | |
| Sodium alginate | |
| Sodium aluminate | |
| Sodium carbonate | |
| Sodium carboxymethylcellulose | Contains not less than 95 percent sodium carboxymethylcellulose on a dry-weight basis, with maximum substitution of 0.9 carboxymethylcellulose groups per anhydroglucose unit, and with a minimum viscosity of 15 centipoises for 2 percent by weight aqueous solution at 25 °C; by the "Viscosity of Cellulose Gum" method prescribed in the Food Chemicals Codex, pp. 1128-1129. |
| Sodium glucoheptonate | Less than 1 part per million cyanide in the sodium glucoheptonate. |
| Sodium hexametaphosphate | |
| Sodium humate | |
| Sodium hydroxide | |
| Sodium lignosulfonate | |
| Sodium metabisulfite | |
| Sodium metasilicate | |
| Sodium nitrate | |
| Sodium phosphate (mono-, di-, tri-) | |
| Sodium polyacrylate | |
| Sodium polymethacrylate | |
| Sodium silicate | |
| Sodium sulfate | |
| Sodium sulfite (neutral or alkaline) | |
| Sodium tripolyphosphate | |
| Sorbitol anhydride esters: A mixture consisting of sorbitan monostearate as defined in § 172.842 of this chapter; polysorbate 60 ((polyoxyethylene (20) sorbitan monostearate)) as defined in § 172.836 of this chapter; and polysorbate 20 ((polyoxyethylene (20) sorbitan monolaurate)), meeting the specifications of the Food Chemicals Codex, pp. 825-827. | The mixture is used as an anticorrosive agent in steam boiler distribution systems, with each component not to exceed 15 milligrams per kilogram in the steam. |
| Tannin (including quebracho extract) | |
| Tetrasodium EDTA | |
| Tetrasodium pyrophosphate |
| Substances | Limitations |
| Cyclohexylamine | Not to exceed 10 parts per million in steam, and excluding use of such steam in contact with milk and milk products. |
| Diethylaminoethanol | Not to exceed 15 parts per million in steam, and excluding use of such steam in contact with milk and milk products. |
| Hydrazine | Zero in steam. |
| Morpholine | Not to exceed 10 parts per million in steam, and excluding use of such steam in contact with milk and milk products. |
| Octadecylamine | Not to exceed 3 parts per million in steam, and excluding use of such steam in contact with milk and milk products. |
| Trisodium nitrilotriacetate | Not to exceed 5 parts per million in boiler feedwater; not to be used where steam will be in contact with milk and milk products. |
21 C.F.R. §173.310