A coated tablet is not just a smoother-looking product — the coating is what stops a moisture-sensitive active from absorbing humidity, covers an odour or bitter taste the fill itself cannot mask, and in some formulas, carries the white colour brands expect a tablet to have. Which coating type, and which colourant inside it, is a specification decision with real regulatory differences between Japan and the EU.
This guide covers film, sugar and shellac coatings, what each does for moisture, odour and taste, and the titanium dioxide question that now divides EU and Japanese practice.
Health supplements are foods, not medicines, and are not a substitute for medical treatment.
💬 Choosing a tablet coating for a Japan-made product? We confirm the coating and colourant against your target markets before quotation. See Japan-made supplement OEM.
Film, sugar or shellac coating
Film coating is the fastest and thinnest modern option; sugar coating is thicker and slower to apply but gives a traditional smooth, hard shell; shellac coating is used mainly as a moisture barrier or glaze rather than the main coating layer.
| Coating type | What it is | Typical use | Watch-outs |
|---|---|---|---|
| Film coating | A thin polymer layer (commonly HPMC-based) applied by spraying a coating solution onto tumbling tablets | The default for most modern supplement tablets | Fast, low added weight, but offers less taste-masking than a thick sugar coat |
| Sugar coating | Multiple layers of sugar syrup built up over many passes, then polished | Traditional confectionery-style tablets | Slower and more labour-intensive process; adds meaningful weight and size to the tablet |
| Shellac coating (as a sub-coat or glaze) | A resin-based moisture barrier or gloss layer, often under a film or sugar coat rather than as the sole coating | Moisture protection and shine, sometimes combined with another coating type | Not vegetarian or vegan, since shellac is insect-derived |
Moisture, odour and taste masking
A coating’s practical job is usually not appearance but protection — keeping moisture out of a hygroscopic fill, and keeping an unpleasant odour or taste from reaching the consumer before the tablet is swallowed.
| Function | How the coating helps |
|---|---|
| Moisture barrier | A continuous film or a shellac-containing sub-coat slows water vapour reaching a moisture-sensitive fill, extending shelf life |
| Odour masking | A sealed coating traps a strong-smelling active (some B vitamins, certain botanicals) inside the tablet core |
| Taste masking | A coating delays the fill dissolving until past the tongue, which matters for a bitter mineral or amino acid tablet in particular |
A brand with a moisture-sensitive or strong-smelling active should treat the coating as part of the stability plan, not a cosmetic finish added at the end — the coating thickness and continuity, not just the coating material, is what determines how well it performs this job.
💬 Formulating a moisture-sensitive or strong-tasting active into a tablet? Tell us the active and we recommend a coating approach before quotation.
Titanium dioxide: the EU ban and Japan’s different position
The EU withdrew authorisation for titanium dioxide (E171) as a food additive in 2022, while Japan’s food safety authorities have reviewed the same evidence and kept it authorised — the two markets currently disagree, and a tablet sold in both needs two different white-colourant approaches.
| Market | Status | What changed |
|---|---|---|
| EU | Titanium dioxide (E171) authorisation as a food additive was withdrawn by Commission Regulation (EU) 2022/63, which entered into force on 7 February 2022, with a transition period allowing products already made under the old rules to be sold until 7 August 2022 | EFSA had concluded it could no longer rule out a genotoxicity concern and so could not confirm the additive was safe |
| Japan | Titanium dioxide remains a designated (approved) food additive; Japan’s Food Safety Commission reviewed the EU’s evidence and concluded in November 2023 that there was no safety concern from current knowledge at the levels typically used as a food additive, and the Ministry of Health, Labour and Welfare’s additives subcommittee found no basis to change its risk management | Japan’s expert review reached a different conclusion from the EU’s, based on the same underlying EFSA opinion |
For a tablet coating formulated for both markets, this means the white colourant needs two versions — a titanium-dioxide-based white coating is not usable in the EU regardless of what is permitted in Japan, and the EU-compliant alternative (typically calcium carbonate or another approved white pigment, confirmed for your specific formula) needs its own compatibility check against the coating base and the fill. Do not assume a Japan-formulated white tablet can simply be sold into the EU unchanged.
The check that comes first
Every coating material and colourant must be permitted as a food additive in each market the product will be sold in, checked separately rather than assumed from one market to the next.
Titanium dioxide is the clearest current example of a coating ingredient that is legal in one major market and not in another, but it is not the only one — any colourant or coating polymer should be checked market by market before a formula is fixed. See the Japan-made supplement OEM page, and compare with our hard capsule shell and enteric capsule guides for how the same food/medicine and market-by-market checks apply to capsule materials.
Before you ask for a quotation
A factory can quote a coated tablet accurately once the coating type, colourant and target markets are fixed.
- Coating type: film, sugar or a shellac-containing sub-coat
- Colourant, and whether titanium dioxide is acceptable in every target market
- Moisture sensitivity, odour or taste-masking requirements of the fill
- Vegetarian or vegan claims needed (shellac affects this)
- Countries you will sell in
💬 Ready to specify a coated tablet made in Japan? Send us the fill and target markets and we confirm the coating and colourant before quotation.
Frequently asked questions
1. Can a titanium-dioxide-coated tablet made in Japan be sold in the EU?
Not as formulated. The EU withdrew titanium dioxide’s authorisation as a food additive in 2022, so a coating relying on it needs reformulating with an EU-approved white colourant before sale in the EU, even though Japan still permits it.
2. Why does Japan still allow titanium dioxide when the EU banned it?
Japan’s Food Safety Commission reviewed the same EFSA evidence that led to the EU ban and concluded in November 2023 that there was no safety concern at typical food-additive use levels, reaching a different risk conclusion from EFSA’s.
3. Is sugar coating still used for supplement tablets?
Yes, though less often than film coating, mainly for a traditional confectionery-style tablet where the thicker, harder shell is part of the product’s character rather than for cost or speed.
4. Does a film coating help with a bad-tasting tablet?
Yes, a continuous film coating delays the fill dissolving until past the tongue, which is one of the main reasons a bitter mineral or amino acid tablet is coated rather than sold uncoated.
5. Is shellac coating vegetarian?
No. Shellac is secreted by the lac insect, so a shellac-containing coating or sub-coat is not suitable for a strict vegetarian or vegan claim, even where it is legally permitted as a food additive.
Sources: Commission Regulation (EU) 2022/63 withdrawing authorisation of titanium dioxide (E171) as a food additive, in force 7 February 2022 with transition to 7 August 2022 (eur-lex.europa.eu/eli/reg/2022/63/oj/eng; reedsmith.com; merieuxnutrisciences.com); Japan Food Safety Commission additives expert panel conclusion, November 2023, and Ministry of Health, Labour and Welfare Pharmaceutical Affairs and Food Sanitation Council additives subcommittee position, reported via caa.go.jp and fsc.go.jp policy materials (caa.go.jp/policies/council/fssc/meeting_materials/assets/fssc_cms102_240604_12.pdf; fsc.go.jp/foodsafetyinfo_map/nisankatitan_kaisetu.html); titanium dioxide’s original designation as a food additive in Japan in 1983 (Showa 58), referenced in the same CAA materials. Checked on 25 September 2026.