Gelatin vs HPMC Capsules: How Manufacturers Choose

Gelatin and HPMC (hypromellose) are the two shell materials behind almost every two-piece hard capsule made today. Both run on standard encapsulation equipment and both come in sizes 000 to 4, so the choice usually comes down to four things: what you are filling, what your label says, where the product will be stored, and cost per thousand capsules.

The short answer

• Choose gelatin for most powder and granule fills when an animal-derived shell is acceptable to your customers. It is the industry standard, it runs fast on high-speed lines and it usually has the lowest unit cost.
• Choose HPMC when you need a vegan or vegetarian claim, when the fill is hygroscopic or moisture-sensitive, or when the fill could react with gelatin.

How the two materials differ

Factor	Gelatin capsules	HPMC capsules
Source	Animal collagen (bovine or porcine)	Plant cellulose (hydroxypropyl methylcellulose)
Typical shell moisture	About 13–16%	Typically 3–7%
Label positioning	Halal or Kosher when the gelatin is certified	Vegan and vegetarian; suits clean-label lines
Moisture-sensitive fills	Shell water can migrate into hygroscopic fills	Lower water content protects hygroscopic actives
Low-humidity storage	Can become brittle if over-dried	Stays flexible at lower humidity
Reactive fills	Aldehydes and some excipients can cross-link gelatin and slow dissolution	Not prone to gelatin-type cross-linking
Unit cost	Usually lower	Usually higher

1. Start with the fill

Most vitamins, minerals and botanical powders run well in gelatin. Look harder at HPMC when the fill:

• Absorbs water easily, such as some probiotics, enzymes, effervescent blends and certain plant extracts. Water moving from a gelatin shell into the fill can reduce potency or cause clumping, and the shell itself can become brittle as it dries out.
• Contains reactive compounds, such as aldehydes or ingredients that can form them. These can cross-link gelatin over time and slow how fast the capsule opens.

If you are unsure, run a short stability study with both shells before committing to a large order.

2. Match the shell to your label claims

A vegan or vegetarian claim rules out gelatin. For Halal or Kosher products, the shell must carry the matching certification; ask your supplier for the certificate and keep it in your supplier qualification file. Capsules Hub gelatin capsules are made from Halal-certified bovine gelatin.

3. Think about where the product will be stored

Gelatin shells hold more water and react more to the humidity around them: very dry rooms can make them brittle, very humid rooms can make them soft. HPMC tolerates lower humidity better. For both materials, follow the storage conditions on the product specification; our FAQ gives typical ranges.

4. Check machinability and dissolution

Both materials are made as standard two-piece hard capsules that run on automatic and semi-automatic encapsulators. HPMC can need small machine adjustments when you switch from gelatin, so plan a trial run. Dissolution and disintegration behaviour depends on the grade of capsule, so compare the specification sheets and, for pharmaceutical products, confirm the method your release testing uses.

5. Compare the total cost, not only the price

Gelatin usually wins on price per thousand capsules. HPMC can still be the cheaper option overall when it reduces stability failures, rejected batches or the need for extra desiccant and packaging protection.

Need enteric release?

Both materials are available as enteric coated capsules for acid-sensitive actives such as probiotics and enzymes, so the gelatin-or-HPMC decision still applies.

Next steps

See our gelatin capsules and HPMC capsules, check volumes in the capsule size chart, or request a bulk quote with your size, colour and quantity.