Short answer: use food-grade silicone for anything that touches food; consider TPE for non-food parts where cost matters. One important caveat — food-grade and standard silicone are practically indistinguishable by eye, touch or even bounce. Colour, smell and the "burn test" are all unreliable. Only two things settle it: the compound grade and a third-party test report.
First, a common misconception: food-grade and standard silicone are chemically the same family (polysiloxanes). The difference is not "is it silicone" but formulation purity, process control, and whether it has been validated against the food-contact regulations of your target market. TPE, by contrast, is a completely different material system — a distinction that is frequently blurred.
| Dimension | Food-grade silicone | Standard industrial silicone | TPE |
|---|---|---|---|
| Material family | Polysiloxane, food-contact grade | Polysiloxane, industrial grade | Thermoplastic elastomer (not silicone) |
| Heat resistance | Roughly −40 °C to +230 °C; oven and boiling safe | Roughly −40 °C to +200 °C | Roughly −30 °C to +90 °C; deforms when hot |
| Compliance route | Food-contact validation for the target market: FDA 21 CFR 177.2600, LFGB, GB 4806.11 | Typically no food-contact validation | Some grades are food-contact capable; confirm case by case |
| How to verify | Check grade + third-party report; appearance tells you nothing | Same; without a report, compliance is unproven | Burn odour and residue differ noticeably, but reports still govern |
| Aging and lifespan | Good anti-yellowing, long service life | Moderate | Ages and gets tacky; performance degrades faster |
| Surface feel | Dry, low dust pickup | Dry | Tacky, picks up dust |
| Processing | Compression or liquid injection, requires curing | Same as left | Injection molded, no curing, short cycle |
| Material and unit cost | Higher | Moderate | Lower, and scrap can be recycled |
| Recyclability | Thermoset, cannot be remelted | Thermoset, cannot be remelted | Thermoplastic, recyclable |
| Typical applications | Teats, feeding ware, baking mats, seals, drinkware | Industrial seals, damping pads, non-food parts | Grips, tool overmolds, soft non-food housings |
Four Typical Scenarios
Making a food-contact product — which one?
Choose food-grade silicone; there is little room for compromise. Beyond the compound itself, process matters: release agents, post-curing and cross-contamination on the shop floor all affect final compliance. So when vetting a supplier, ask not only for the grade and report but also whether food-contact parts run on dedicated lines or under a dedicated cleaning procedure — running industrial parts and food parts on the same machine is a real risk.
Tight budget, non-food part — is TPE acceptable?
Yes, provided you accept its limits: a ceiling near 90 °C, tackiness and aging over time, and deformation under heat. If the product sees sunlight, sits near a heat source or lives outdoors, TPE often fails — and rework costs more than the material savings. On the other hand TPE is thermoplastic and recyclable, which is a genuine plus in some markets.
How do I verify a supplier’s "food-grade" claim?
Ask three things, in this order. First, what is the specific compound grade? (a supplier should name the grade, not just answer "food-grade"). Second, is there a third-party test report? And it must match your target market — FDA 21 CFR 177.2600 for the US, LFGB for the EU, GB 4806.11 for China. Third, does the report cover the actual test items and conditions you need (migration, sensory, heavy metals)? If you cannot get a grade or the "report" is only a self-declaration, treat compliance as unproven.
The product goes in an oven or microwave — can TPE handle it?
No. TPE tops out around 90 °C; oven and microwave heating will deform, soften or even degrade it. These applications call for food-grade silicone (typically rated near 230 °C and able to take boiling water, steam, microwaves and oven use). If your product needs both high heat and food contact, there is effectively no alternative material.
Selection Checklist
- First determine whether the part touches food — this alone decides the material route
- Identify the target market, then pin down which food-contact regulation applies (FDA / LFGB / GB 4806.11)
- Write the temperature ceiling as a concrete figure and condition (brief peak vs continuous)
- Request the compound grade; do not accept a vague "food-grade" answer
- Request third-party test reports and check that the tested items match your needs
- Confirm whether food parts run on dedicated lines or a dedicated cleaning procedure
- Confirm that release agents and post-curing are compatible with food-contact requirements
- If considering TPE, assess in advance the temperature, lifespan and appearance changes it will show
FAQ
Can the burn test or smell tell me if it is food-grade?
Not as a basis for judgment. Burning can roughly separate silicone from other elastomers (silicone tends to leave a white ash with a milder odour), but it cannot distinguish food-grade from industrial-grade silicone — they share the same backbone, and the difference lies in formulation purity and compliance validation, which combustion does not reveal. The test also carries safety and fume risks. The proper route is simply to request the grade and the test report.
Is food-grade silicone always more expensive?
Usually somewhat more, though the gap is often smaller than expected. Food-contact grades demand higher raw-material purity, tighter catalyst systems and better process control, plus testing costs. But the molding process is the same and tooling carries over, so the total manufacturing difference concentrates in material and testing rather than doubling. What should genuinely raise suspicion is a quote far below market that still claims food grade — that is precisely when to demand the grade and report.
Can one product combine silicone and TPE?
Yes — common in overmolding (a rigid substrate plus a soft-touch layer). The catch is compatibility: silicone and TPE usually need a primer or a dedicated bonding process to adhere well, and straight two-shot molding often fails to bond. If part of the product touches food, the contact layer must use a compliant grade, and the adhesive itself must be included in the compliance assessment.
LXYSILICONE can support food-contact testing and provide third-party reports (SGS and similar) matched to your target market, and can help confirm grade, hardness and process alignment at the sampling stage.