Porcine Gelatin and HPMC Capsules — Allergen Labelling, Jelly Strength and Selection

The first split is labelling, not physical properties

Comparisons of capsule shells usually open with disintegration, moisture and price. In practice the first thing that bites is labelling. Use gelatin and the product falls within recommended allergen labelling; use HPMC and it does not. That difference reaches all the way to the printed packaging, which makes it a decision to settle before trial production, not after.

• Gelatin — an item equivalent to specified raw materials (recommended labelling), under the Director-General notification “Concerning the Food Labelling Standards” (Shoku-Hyo No. 139, 30 March 2015)
• HPMC — designated additive No. 328 (Hydroxypropyl Methylcellulose). Not among the specified raw materials or equivalent items

The detail that gets missed: within the twenty recommended items, “gelatin” is listed separately alongside “pork” and “beef”. Where a porcine-skin gelatin is used, checking only the pork entry and recording “not applicable” leaves the gelatin entry blank. On the list, the source animal and the gelatin are two different items.

Gelatin is not an additive — a difference of category

The other easy confusion is the regulatory category. HPMC is a designated additive — an item designated as an additive. Gelatin, by contrast, appears in neither of the lists we maintain: 476 designated additives and 327 existing additives. It is handled as a food raw material.

That distinction affects how the ingredient name is written on the label, which compendium the specification should reference, and which tests to ask the supplier for. Treating both as “the capsule shell” and requesting the same specification template leaves fields that one of them cannot fill.

Selecting a gelatin grade — jelly strength (P100–P300)

The number in a gelatin grade code is its jelly strength. FONTIA’s porcine skin gelatin (CAS 9000-70-8) is available in four grades.

• Porcine Skin Gelatin P100 — jelly strength 100 g or above
• P250 — jelly strength 250 g or above
• P280 — jelly strength 280 g or above
• P300 — jelly strength 300 g or above

A higher figure means a firmer gel. Where texture is itself part of the product specification — gummies, jellies — this value works directly on the result. Where the gelatin is dissolved in use, solubility and viscosity often matter more than strength.

One procurement caution: jelly strength is measured under defined conditions. Comparing “250 g or above” against another supplier’s “250 g or above” is not a like-for-like comparison unless the test conditions match. When changing supplier, confirm the test conditions stated on the COA alongside the specification value. Identical numbers producing different firmness is precisely where this goes wrong.

HPMC capsule specifications

HPMC capsules (CAS 9004-65-3) are food-grade hard capsules. Available sizes and colour:

• Sizes — #00EL, #00, #0, #1, #2
• Colour (cap/body) — Clear/Clear

Size follows from fill volume. Fix the bulk of the formulation first, then choose the size; doing it the other way round means reworking the formulation when it will not fit. The same fill weight needs a different size depending on bulk density, so measuring the bulk with the actual materials before trial production is the reliable route.

Which to choose — the order of the decision

• Labelling and claims — HPMC where plant-origin or vegetarian positioning is part of the proposition, and equally where recommended allergen labelling is to be avoided
• Destination requirements — in markets with religious or dietary constraints, the source animal is the issue. Confirm this first where export is involved
• Compatibility with the fill — for hygroscopic fills or moisture-sensitive actives, the moisture behaviour of the shell becomes the question. Confirm stability with the actual formulation
• Cost and supply — gelatin capsules are generally the cheaper option, though this shifts with volume and lead time. Sharing annual requirements early makes allocation easier

The sequence that avoids rework is to settle labelling and destination requirements first, then work through physical properties and price. Starting from physical properties risks having the decision overturned later by a labelling requirement.

For specifications, samples or a quotation, please use the contact form. Tell us the outline of the formulation to be filled — bulk, hygroscopicity, intended size — and we will advise alongside. The wider picture on allergen labelling is covered in Allergen Labelling: the April 2026 Revision.