Stainless steel is a popular material for food handling due to its durability, corrosion resistance, and ease of cleaning. However, the suitability of different grades for food contact, particularly when placing hot food directly on them, varies. This article summarizes what published tests and technical sources say about stainless steel grades 410, 430 and 204 (204Cu).
Stainless Steel Grade 410
Properties and Compliance:
- Chromium Content: 11.5% to 13% (Meerkits).
- Nickel Content: Less than 1% (Meerkits).
- Corrosion Resistance: Moderate. Grade 410 is mainly used for cutlery blades (Meerkits).
- Test data: Grade 410 was not among the grades tested in the migration study cited below, so we do not have comparable metal-release results for it.
- Regulation: The FDA does not certify steel grades; compliance depends on the finished article and its use.
Conclusion: As a precaution, we do not recommend grade 410 for trays that hold hot or acidic food. Choose a grade that has published migration test data.
Stainless Steel Grade 430
Properties and Compliance:
- Chromium Content: About 16% (AAA Metals, Casting Blog).
- Nickel Content: Minimal (Casting Blog).
- Corrosion Resistance: Moderate to good, but lower than grade 304, particularly with salty or very acidic food.
- Heat Resistance: Suitable for high temperatures, up to about 850°C intermittently (Casting Blog).
- Migration test: In a study carried out by KTH Royal Institute of Technology for the stainless steel industry (Team Stainless), grade 430 released metals below the Council of Europe specific release limits, using a citric acid test (pH 2.4) at 70°C for 2 hours followed by 40°C for up to 240 hours.
Conclusion: Grade 430 passed this migration test and is suitable for hot food contact on trays. For very salty or acidic food, grades 304 or 316 remain the usual choice.
Stainless Steel Grade 204 (204Cu)
Properties and Compliance:
- Chromium Content: About 16% (AAA Metals).
- Nickel Content: About 1.6% (AAA Metals). Grade 204 belongs to the 200 series, where part of the nickel is replaced by manganese.
- Corrosion Resistance: Good in mild conditions, but lower than grade 304, so it is not equivalent to 304 for salty or acidic food.
- Migration test: In the same KTH study, grade 204Cu released chromium, nickel and manganese below the Council of Europe specific release limits.
Conclusion: Grade 204Cu passed this migration test and is suitable for hot food contact on trays, with less corrosion resistance than 304.
Property | AISI 410 | AISI 430 | AISI 204 (204Cu) |
Chromium content (%) | 11.5-13 | About 16 | About 16 |
Nickel content (%) | <1 | Minimal | About 1.6 |
Corrosion resistance | Moderate | Moderate to good | Good in mild conditions (below 304) |
Council of Europe migration test (KTH study) | Not tested in this study | Below limits | Below limits |
Common applications | Cutlery blades | Brewing, dairy equipment | Food processing equipment |
Hot food on trays | Not recommended as a precaution (no test data) | Suitable (tested) | Suitable (tested) |
The FDA does not certify steel grades, so no grade is "FDA approved". The KTH study was commissioned by the stainless steel industry.
Advice for Using Stainless Steel Trays
- For Hot Food Contact: Use trays made from a grade with published migration test data, such as 430, 204Cu, or the 304 and 316 grades.
- Avoid Using: Trays made from an untested grade, such as 410, for hot or acidic food.
- Salty or acidic food: Prefer grade 304 or 316, which resist corrosion better than 430 and 204.
- Cleaning and Maintenance: Regularly clean and maintain stainless steel trays to preserve their corrosion resistance. Avoid abrasive cleaning tools that can damage the surface.
References
- "Is 410 stainless steel good enough for food contact?" Meerkits.
- "Safe Food Preparation Using Stainless Steel", summary of the KTH Royal Institute of Technology report for Team Stainless (Council of Europe test guideline). PDF
- "304 vs 430 stainless steel" Casting Blog.
- "What is the Best Food Grade Stainless Steel?" AAA Metals.
- 430 Stainless Steel (UNS S43000) – Composition, Properties, and Uses Link
By choosing a grade with published test data and looking after your trays, you can use stainless steel safely and durably for food contact, including hot food.