FDA 21 CFR 177.2600 — buyer's reading guide

FDA 21 CFR 177.2600 is the U.S. regulation for rubber articles intended for repeated food contact. Every silicone gasket, baking mold, baby soother and tubing that ships into the U.S. food industry must meet it. The text is dense and most of the load-bearing requirements are in the cross-referenced CFR sections. This page rewrites the rule in the language a procurement or QA team uses.

Scope — what is and is not covered

In scope. Rubber articles intended for repeated use in contact with aqueous and fatty foods. That includes silicone baking molds, sealing gaskets on coffee machines, baby bottle nipples, ice trays, food container lids, tubing in beverage dispensers, and peristaltic pump tubing used in food processing. The rule applies to the finished article, not the raw polymer — so the cure system, post-cure and the surface finish all count.

Out of scope. Single-use disposable food contact articles (these fall under 175.300 or other parts of 177). Medical devices that contact the body internally (regulated under USP Class VI and ISO 10993 instead). Toys that contact saliva but are not food contact (regulated under 16 CFR Part 1501 and EN 71).

Cross-references. 177.2600 explicitly defers several limits to other sections — 175.300 (extraction conditions), 178.3700 (catalysts), and 180.22 / 180.30 (specific extractable substances). A buyer who reads only 177.2600 will miss half of what the rule actually requires.

The two extractable limits

Aqueous extractables. The finished article is refluxed with distilled water for 7 hours, then for 2 more. The extract is evaporated; the total non-volatile residue must not exceed 20 mg per square inch of food-contact surface (about 3.1 mg per cm²).

Fatty extractables. For articles intended for contact with fatty foods, a separate extraction with n-hexane or ethyl acetate is performed. The limit depends on the form of the article and the time-temperature conditions. The extract residue limit for repeated-use articles in fatty-food service is 175 mg per square inch under some conditions.

These are the two numbers your compliance certificate has to address. If the certificate only states "FDA compliant" without showing the extraction data, it is not a 177.2600 certificate — it is a marketing claim.

Platinum-cured vs peroxide-cured silicone

Platinum-cured (addition cure). Two-part system: vinyl-functional polymer + SiH crosslinker, catalysed by ppm-level platinum complex. Cures without by-products. Lower extractables than peroxide cure. The default for baby-care, medical, and any application where the part is in prolonged contact with the food.

Peroxide-cured (free-radical cure). Organic peroxide (typically 2,4-dichlorobenzoyl peroxide or dicumyl peroxide) decomposes under heat to generate radicals that crosslink the polymer. By-products include residual peroxide, decomposition acids and short-chain volatiles. Lower cost but higher extractables. Acceptable for some single-use or short-contact applications; usually post-baked to drive off volatiles.

Post-baking. A 200 °C / 4 h post-cure in a vented oven reduces peroxide-cured extractables by 60–80 % and is standard for food-contact parts. Post-baking is not optional for peroxide-cured silicone used in baby-care.

Why we default to platinum cure. All Silicraft food-contact production runs in our Shenzhen food-grade cell, on LSR injection machines dedicated to platinum-cured compounds. We run peroxide-cured HTV only when the customer asks for it (rare for food contact, common for industrial gaskets where extractables do not matter).

What a compliance file should contain

When you buy a silicone food-contact part from us, the compliance package should contain:

1. Certificate of Compliance referencing 21 CFR 177.2600 by section.
2. TDS for the specific compound used (not a generic data sheet).
3. Extraction test report from a third-party lab (SGS, Intertek, TÜV Rheinland) showing actual extractables on the finished article, under both aqueous and fatty conditions.
4. NDA before any drawing or formulation detail is shared — we sign these as a matter of course.
5. Lot traceability from raw batch to finished article, retained for the regulatory life of the product.

If your supplier cannot produce items 3 and 4, escalate. Item 3 in particular is what the FDA inspector will ask for in the event of an audit.

FAQ — FDA 21 CFR 177.2600

Does 177.2600 cover baby bottle nipples?

Yes. Nipples, pacifiers and teethers fall under 177.2600 if they are intended for food contact. Infant-care products in the U.S. also fall under 16 CFR Part 1501 (small parts) and consumer product safety standards.

Is LFGB §31 stricter than FDA 177.2600?

On most parameters, yes. LFGB §31 (the German food-contact regulation) tests at higher temperatures and uses more aggressive extraction conditions. A silicone that passes LFGB typically passes FDA, but not always the reverse.

Can a part be FDA compliant without post-baking?

Yes, if it is platinum-cured. Platinum cure generates no volatiles to begin with. Peroxide-cured parts without post-baking usually fail extractables limits.

How long is a 177.2600 certificate valid?

The certificate is valid for the formulation and process used. If the formulation changes (different compound, different supplier, different cure cycle), a new certificate is required. We re-issue certificates annually or whenever a TDS changes.