---
kind: "unit"
title: "21"
title_heading: "Food and Drugs"
key: "chI/subchB/part173"
level: "part"
label: "Part 173"
heading: "Secondary Direct Food Additives Permitted in Food for Human Consumption"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/21/chI-subchB-part173"
sections_count: 57
---

# Part 173 — Secondary Direct Food Additives Permitted in Food for Human Consumption

Title 21 C.F.R. — Food and Drugs › Chapter I — Food and Drug Administration, Department of Health and Human Services › Subchapter B — Food for Human Consumption

## Contents

- [Subpart A — Polymer Substances and Polymer Adjuvants for Food Treatment](/cfr/21/chI-subchB-part173-subpartA.md)
- [Subpart B — Enzyme Preparations and Microorganisms](/cfr/21/chI-subchB-part173-subpartB.md)
- [Subpart C — Solvents, Lubricants, Release Agents and Related Substances](/cfr/21/chI-subchB-part173-subpartC.md)
- [Subpart D — Specific Usage Additives](/cfr/21/chI-subchB-part173-subpartD.md)