THE SCIENCE
Not all stainless steel is the same.
Why Grades Matter
"Stainless steel" is a category, not a single material. There are over 150 grades, each with different compositions and properties. For food containers, the grade determines:
- How well it resists corrosion
- Whether it reacts with your food
- How long it lasts
- Whether it's safe for cooking vs. just storage
If a product just says "stainless steel" without specifying the grade, that's not transparency — that's vagueness.
Four grades you'll encounter.
Grade 201 — The Budget Option
| Composition | 16-18% Cr, 3.5-5.5% Ni, 5.5-7.5% Mn |
| Corrosion resistance | Low |
| Food safe | Technically yes, but lower corrosion resistance means higher metal release over time |
| Our view | Not suitable for food storage that will be heated or used long-term |
Grade 304 (18/8) — The Food-Grade Standard ← What we use
| Composition | 18% Cr, 8% Ni |
| Corrosion resistance | High |
| Food safe | Yes — the benchmark for food contact materials worldwide |
| Common in | Hospital equipment, commercial kitchens, high-quality cookware |
| Our view | The right grade for food storage. Proven, tested, well-understood |
Grade 316 — The Surgical/Marine Grade
| Composition | 16% Cr, 10% Ni, 2% Mo (molybdenum) |
| Corrosion resistance | Very high (resists chlorides) |
| Our view | Superior corrosion resistance, but overkill for food storage. Added cost without meaningful kitchen benefit |
Grade 430 — The Ferritic Option
| Composition | 16-18% Cr, <0.75% Ni |
| Corrosion resistance | Moderate |
| Our view | Fine for appliance surfaces, not ideal for repeated food contact |
How to verify what you're buying.
What actually works:
- Look for grade markings. Reputable manufacturers stamp the grade on the product. Our containers are stamped SS304.
- Ask for a mill certificate. This traces the steel back to the mill that produced it.
- Independent composition testing. Chemical composition analysis reads the elemental composition. We commission this independently and publish the results.
What to watch for:
- "Stainless steel" with no grade specified — could be any grade
- "Food grade stainless steel" — marketing term, not a grade specification
- "18/10" — this is 316 or similar. Nothing wrong with it, but check the price