---
kind: "section"
citation: "21 C.F.R. § 177.2910"
title: "21"
number: "177.2910"
heading: "Ultra-filtration membranes."
url: "https://uscodex.org/cfr/21/177.2910"
---

# §177.2910. Ultra-filtration membranes.


Ultra-filtration membranes identified in paragraphs [(a)(1)](#a-1), [(a)(2)](#a-2), [(a)(3)](#a-3), and [(a)(4)](#a-4) of this section may be safely used in the processing of food, under the following prescribed conditions;

- (a)
  - (1) Ultra-filtration membranes that consist of paper impregnated with cured phenol-formaldehyde resin, which is used as a support and is coated with a vinyl chloride-acrylonitrile copolymer.
  - (2) Ultra-filtration membranes that consist of a sintered carbon support that is coated with zirconium oxide (CAS Reg. No. 1314-23-4) containing up to 12 percent yttrium oxide (CAS Reg. No. 1314-36-9).
  - (3) Ultra-filtration membranes that consist of an aluminum oxide support that is coated with zirconium oxide (CAS Reg. No. 1314-23-4) containing up to 5 percent yttrium oxide (CAS Reg. No. 1314-36-9).
  - (4) Ultrafiltration membranes that consist of a microporous poly(vinylidene fluoride) membrane with a hydrophilic surface modifier consisting of hydroxypropyl acrylate/tetraethylene glycol diacrylate copolymer.
- (b) Any substance employed in the production of ultra-filtration membranes that is the subject of a regulation in parts [174](/cfr/21/part174.md), [175](/cfr/21/part175.md), 176, 177, 178 and [§ 179.45](/cfr/21/179.45.md) of this chapter conforms with the specifications of such regulation.
- (c) Ultra-filtration membranes are used in the physical separation of dissolved or colloidally suspended varying molecular size components of liquids during the commercial processing of bulk quantities of food.
- (d) Ultra-filtration membranes shall be maintained in a sanitary manner in accordance with good manufacturing practice so as to prevent potential microbial adulteration of the food.
- (e) Ultrafiltration membranes identified in [paragraph (a)(4)](#a-4) may be used to filter aqueous or acidic foods containing up to 13 percent of alcohol at temperatures not to exceed 21 °C (70 °F).
- (f) To assure safe use of the ultra-filtration membranes, the label or labeling shall include adequate directions for a pre-use treatment, consisting of conditioning and washing with a minimum of 8 gallons of potable water prior to their first use in contact with food.
- (g) Acrylonitrile copolymers identified in this section shall comply with the provisions of [§ 180.22](/cfr/21/180.22.md) of this chapter.

## Notes

### Amendments

[42 FR 14572, Mar. 15, 1977, as amended at 53 FR 17925, May 19, 1988; 58 FR 48599, Sept. 17, 1993; 60 FR 54426, Oct. 24, 1995]

### Authority

Authority: 21 U.S.C. 321, 342, 348, 379e.

### Source

Source: 42 FR 14572, Mar. 15, 1977, unless otherwise noted.

### Amendments

[42 FR 14572, Mar. 15, 1977, as amended at 53 FR 17925, May 19, 1988; 58 FR 48599, Sept. 17, 1993; 60 FR 54426, Oct. 24, 1995]