21 CFR 176.170 Explained | Paper Food Packaging Compliance

21 CFR 176.170 is the U.S. Food and Drug Administration regulation that governs substances used in paper and paperboard - including molded fiber (molded pulp) and bagasse - that touches aqueous or fatty food. For buyers, it answers one practical question: can this packaging be used with my food, at my temperature, without transferring unacceptable amounts of material into the food? The answer always depends on the Condition of Use the product was tested under.

What is 21 CFR 176.170?

Section 176.170 sits in Title 21 of the Code of Federal Regulations, Part 176, which covers indirect food additives from paper and paperboard components. It does two things:

It lists permitted substances. Only components identified in the regulation (or otherwise authorized, for example through a food contact notification) may be used in the food-contact surface.

It sets extractive limits. The finished packaging is exposed to food simulants, and the amount of material that migrates out - the extractives - must stay within the regulation's limits, expressed in milligrams per square inch of food-contact surface.

Both parts matter. A passing extractives test shows low migration under the tested conditions; it does not by itself prove that every raw material is a permitted substance. A credible supplier can speak to both.

What are FDA Conditions of Use A–H?

Table 2 of 21 CFR 176.170 defines eight Conditions of Use. Each one reflects how hot the food is and what happens to it in the package. Extractives testing is run with the times and temperatures that match the chosen condition.

Condition	Definition (21 CFR 176.170, Table 2)
A	High temperature heat-sterilized (e.g., over 212°F)
B	Boiling water sterilized
C	Hot filled or pasteurized above 150°F
D	Hot filled or pasteurized below 150°F
E	Room temperature filled and stored (no thermal treatment in the container)
F	Refrigerated storage (no thermal treatment in the container)
G	Frozen storage (no thermal treatment in the container)
H	Frozen or refrigerated storage: ready-prepared foods intended to be reheated in container at time of use

Why this matters for purchasing: a report run under Condition E supports room-temperature use. If your application involves hot-filled food, pasteurization or reheating in the container, ask for data under the condition that matches it.

How does FDA extractives testing work?

The lab exposes the packaging to simulants that stand in for different food types, then weighs the residue that migrates out:

Water - for aqueous foods

n-Heptane - for fatty and oily foods

8% ethanol - for low-alcohol foods and beverages

50% ethanol - for higher-alcohol foods and beverages

Results are reported in mg/in² and compared with the regulation's limit. A result of "n.d." (not detected) means the residue was below the lab's reporting limit.

How do you read a 21 CFR 176.170 test report?

Check the Condition of Use. It should match your food and process, not just say "FDA."

Check which simulants were run. Fatty or oily foods need an n-heptane result.

Compare each result with the limit and look for a clear pass/fail statement.

Check the applicant, date and lab. The report should be issued to the supplier by an independent lab and be reasonably recent.

Watch the wording. FDA does not "approve" or "certify" packaging. Claims such as "FDA approved" are a red flag; "complies with 21 CFR 176.170" backed by a test report is the accurate form.

Does Bio Earth's molded fiber meet 21 CFR 176.170?

Bio Earth's food-contact molded fiber packaging, made from wood pulp and bagasse, has been tested by SGS Taiwan against the extractive limits of 21 CFR 176.170 under Condition of Use E (room temperature filled and stored). All four simulants passed against the 0.5 mg/in² limit:

Simulant	Test conditions	Result (mg/in²)	Limit (mg/in²)
Water	120°F, 24 h	Not detected (<0.2)	0.5
n-Heptane	70°F, 30 min	0.278	0.5
8% ethanol	120°F, 24 h	0.202	0.5
50% ethanol	120°F, 24 h	Not detected (<0.2)	0.5

The full SGS report is available on request. If your application requires hot fill or reheating, we can arrange testing under the matching Condition of Use for your program.

These results apply to our uncoated molded fiber; film-laminated versions are evaluated separately.

FAQ

What is Condition of Use E? Condition E in 21 CFR 176.170 Table 2 means room temperature filled and stored, with no thermal treatment in the container.

Is there such a thing as "FDA-approved" packaging? Not in the usual sense. FDA regulates the substances used in food-contact materials. Packaging complies with regulations such as 21 CFR 176.170; it is not individually approved.

Does 21 CFR 176.170 apply to molded fiber? Yes. Molded fiber is a paper-based material, so its food-contact components fall under the paper and paperboard regulations.

Does a Condition E result cover hot food? No. Condition E covers room-temperature filling and storage. Hot fill, pasteurization and in-container reheating correspond to other conditions (A–D and H).

What does "n.d." mean on the report? Not detected - the result was below the lab's reporting limit.

Need FDA test data matched to your food and temperature? Tell us your application and we will share our reports or arrange testing under the right Condition of Use. Contact: services@bioearthtech.com | www.bioearthtech.com

This article is for general information and is not legal advice. Confirm compliance requirements for your specific application with qualified regulatory counsel.