HPMC vs pullulan – vegan capsules comparison

Among vegan alternatives to traditional gelatin capsules, the most common are HPMC and pullulan (shells). How do these two plant-based substances differ? Which one to choose — HPMC or pullulan? To find out, we invite you to explore the HPMC vs pullulan comparison.

What is HPMC (hypromellose)?

In the production of hard capsules, a plant-based substitute for gelatin can be used — hydroxypropyl methylcellulose, also known as hypromellose (HPMC for short). What is HPMC? It is a semi-synthetic polymer of plant origin derived from plant cellulose — most commonly from wood pulp or cotton.

Applications of HPMC

Hypromellose (HPMC) is a plant-based alternative to traditional gelatin, used in both the pharmaceutical industry and dietary supplements. Due to its excellent chemical and physical stability, HPMC is ideal for the production of hard vegetarian and vegan capsules.

In addition to its use in capsules, hypromellose is also used as a coating ingredient for tablets. HPMC is also applied in the food industry (e.g., as a thickener or emulsifier) and cosmetics (e.g., in gels and creams).

What is pullulan?

Besides HPMC, pullulan is also used in the production of hard capsules. What is pullulan? It is a natural polysaccharide (complex sugar) obtained by fermenting a starch solution (e.g., from corn or tapioca) using fungi of the species Aureobasidium pullulans.

Pullulan – not just capsule shells

Pullulan is used in the pharmaceutical and supplement industries as a gelatin alternative for vegan and vegetarian products. It is mainly used to produce transparent capsule shells.

Pullulan is also used in the food industry (as a food coating to preserve freshness, marked with the symbol E1204). In cosmetics, pullulan is used in masks, serums, and creams as a film-forming agent.

Differences between HPMC and pullulan capsules

Both HPMC and pullulan are plant-based and contain no animal-derived ingredients. That’s why HPMC and pullulan capsules (shells) are suitable for vegans and vegetarians.

However, the two substances differ in their production processes:

• HPMC (hydroxypropyl methylcellulose, also known as hypromellose) is produced from plant cellulose chemically modified — a semi-synthetic compound;
• pullulan is obtained through the fermentation of plant sugars by microorganisms — a fully natural and biodegradable compound.

HPMC vs pullulan – performance properties

HPMC and pullulan also differ in their performance properties:

• HPMC capsules are better suited for moisture-sensitive ingredients because they contain less water (approx. 2–6%) and offer better stability under variable storage conditions;
• pullulan shells offer superior airtightness and oxygen resistance, so they better protect ingredients sensitive to oxidation (e.g., antioxidants or probiotics).

HPMC safety, pullulan safety

Many people wonder whether HPMC is harmful and whether pullulan is harmful. Both HPMC and pullulan have been thoroughly studied and recognized as safe by regulatory bodies (including the FDA, EFSA, and JECFA). These compounds are well tolerated by the body (no toxicity or significant side effects have been reported). Moreover, pullulan has been shown to act as a prebiotic and support beneficial gut bacteria.

HPMC capsules – pros and cons

HPMC capsules offer high chemical and physical stability, require no preservatives, and contain little water (approx. 2–6%). This makes them less susceptible to microbial growth, moisture, and temperature compared to gelatin capsules.
Compared to pullulan, HPMC capsules are widely available and inexpensive to produce. The downsides may include lower oxygen resistance and the fact that hypromellose is a semi-synthetic compound.

Pullulan capsules – pros and cons

Pullulan capsules are 100% natural — they are produced via fermentation of plant sugars. Their biggest advantage is excellent oxygen barrier properties, making them ideal for oxidation-sensitive products such as probiotics and antioxidants.
Pullulan is tasteless, biodegradable, and transparent, giving capsules a more aesthetically pleasing look than HPMC. However, it is more expensive and has a more complex production process, which limits its widespread use.

HPMC or pullulan – which to choose?

The choice between HPMC and pullulan capsules depends mainly on the type of active ingredient, the desired protection against oxidation, and production budget.
HPMC is a more universal and economical solution, suitable for moisture-sensitive ingredients. Pullulan, on the other hand, offers better oxygen barrier properties and thus protects oxidation-sensitive substances — but at a higher cost. If you are looking for a good balance of quality and price, HPMC may be sufficient. However, if a natural composition and high resistance to oxygen and moisture are priorities (e.g., for probiotics), pullulan capsules will be the better option.

HPMC vs pullulan capsules – frequently asked questions

I. What is HPMC?

HPMC (hydroxypropyl methylcellulose, hypromellose) is a semi-synthetic polymer derived from plant cellulose. It is used, among others, to manufacture vegan capsules as a substitute for gelatin.

II. What is pullulan?

Pullulan is a natural polysaccharide (complex sugar) obtained through fermentation involving Aureobasidium pullulans fungi. It is primarily used for producing edible capsule shells and is labeled as food additive E1204.

III. Is HPMC harmful?

No, HPMC is considered safe for human health. It is a chemically inert compound approved for food use and widely used in pharmaceuticals. It does not exhibit harmful or toxic effects.

IV. Is pullulan harmful?

No, pullulan is considered non-hazardous. Toxicological studies have shown no adverse health effects, and pullulan capsules are safe — even beneficial (as pullulan may act as a prebiotic and support good gut bacteria).

V. Which capsules are better: HPMC or pullulan?

It depends on the application. Pullulan is more natural and offers better protection for oxidation-sensitive ingredients but is more expensive. HPMC is cheaper and more readily available.

VI. What are HPMC capsules made of?

HPMC capsules are made from hypromellose, a chemically modified plant cellulose (usually from wood pulp or cotton). The HPMC solution forms a transparent, neutral capsule shell.

VII. What are pullulan capsules made of?

Pullulan capsules are made from pullulan obtained by fermenting starch solution (e.g., from tapioca or corn) by microorganisms. After purification, pullulan is mixed with water and formed into capsules — often without additives, as it forms a strong, transparent shell on its own.

VIII. Are HPMC capsules vegan?

Yes. HPMC is plant-based and contains no animal ingredients, making HPMC capsules suitable for vegans and vegetarians. Similarly, pullulan capsules are also 100% plant-based and vegan.

REFERENCES

1. Burdock, G.A. (2007). Safety assessment of hydroxypropyl methylcellulose as a food ingredient. Food and Chemical Toxicology, 45(12), 2341–2351. https://doi.org/10.1016/j.fct.2007.07.011.
2. Hong, L., Kim, W.-S., Lee, S.-M., Kang, S.-K., Choi, Y.-J., Cho, C.-S. (2019). Pullulan Nanoparticles as Prebiotics Enhance the Antibacterial Properties of Lactobacillus plantarum Through the Induction of Mild Stress in Probiotics, 10, 142. https://doi.org/10.3389/fmicb.2019.00142.
3. Prakash, A., Soni, H., Mishra, A., Sarma, P. (2017). Are your capsules vegetarian or nonvegetarian: An ethical and scientific justification. Indian Journal of Pharmacology, 49(5), 401–404. https://doi.org/10.4103/ijp.IJP_409_17.
4. Singh, R.S., Kaur, N., Hassan, M., Kennedy, J.F. (2021). Pullulan in biomedical research and development – A review. International Journal of Biological Macromolecules, 166, 694–706. https://doi.org/10.1016/j.ijbiomac.2020.10.227.
   Vitamin Manufacture (2020). What is an HPMC Capsule? [online]. Available at: https://www.vitaminmanufacture.co.uk/2020/10/what-is-an-hpmc-capsule [online access: 25.06.2025]