Gelatin vs. HPMC Capsules for the Nutraceutical Industry
What is one of the most popular options for encapsulating nutraceuticals? Two-piece capsules. And in the realm of two-piece capsules there are primarily two choices: gelatin capsules and HPMC capsules.
Gelatin capsules are made from gelatin, an animal product derived from the bones and connective tissues of cows and pigs. HPMC capsules are vegetarian, plant-based capsules. They are made from hydroxypropyl methylcellulose, which is produced through the chemical modification of cellulose, a natural polymer and fiber.
Which is best for your nutraceutical product—gelatin or HPMC two-piece capsules? To answer this question it is helpful to understand the similarities and differences between these choices.
How gelatin and HPMC two-piece capsules are similar
Safe
Both gelatin and HPMC have received the “Generally Recognized as Safe for human consumption” (GRAS) designation from the world’s regulatory authorities. In addition, both have a low likelihood of allergenicity.
Natural
Both gelatin and HPMC are natural products.
“Clean Label” Friendly
Unlike tablets and softgels, the fill material for two-piece capsules can be formulated without binders. This can also make your product easier to digest, as many common binders and excipients can cause digestive problems.
Flexible
Gelatin capsules and HPMC two-piece capsules both work with a broad range of applications, formulations and fill types, including powders, granules, beads, tablets, liquids or even a mix of filling materials. Both have an easy filling process, and both do a good job masking the unpleasant taste and odor of the encapsulated material.
Long-lasting
Under proper storage conditions, both options give you a shelf life of about five years.
Customizable
Both types of two-piece capsules are available in a wide range of sizes and colors, can be made with a variety of finishing options, and can include custom printing on the capsule’s body and/or cap.
How gelatin and HPMC two-piece capsules differ
Consumer preference
HPMC capsules are vegetarian; gelatin capsules are not. This is a more important distinction in the nutraceuticals industry, where many health-conscious consumers are specifically looking for vegetarian products than it is in the pharmaceuticals industry, where many consumers will simply take the medication prescribed without inquiring about its ingredients.
For this reason, all else being equal, HPMC capsules are often the best choice for a nutraceutical product.
Certifications
Whether they are gelatin or HPMC, top quality capsules should be certified cGMP, non-GMO, Kosher and Halal. They should also come with a Composition Certification showing they are free of starches and preservatives. For the European market it is also important that the capsules do not contain titanium dioxide as a colorant.
If you choose HPMC capsules, be sure to choose a brand, such as K-CAPS®, that have received Vegan Registration from the Vegan Society.
If you are using gelatin capsules, be sure to choose a brand, such as G-CAPS®, that is free of BSE (bovine spongiform encephalopathy, also known as “mad cow disease”), as well as TSE (transmissible spongiform encephalopathies) and prion diseases. Prion diseases are a family of progressive neurodegenerative disorders that affect both animals and humans.
Ability to meet API challenges
Moisture content is an important contributor to the stability of many nutraceutical products, such as probiotics and amino acids. With their lower moisture content, HPMC capsules are more suitable for moisture-sensitive or hygroscopic formulations. HPMC capsules are also less prone to problems with brittleness than gelatin two-piece capsules are.
Another technical advantage of HPMC capsules is that they are resistant to cross-linking.
Cost
Because they cost less to produce, gelatin two-piece capsules cost less than HPMC two-piece capsules. Plus, the cost of HPMC capsules has increased due to increased demand.
Machinability
If you do not use a top-quality HPMC capsule, HPMC capsules can be a little harder to run on your filling machines than gelatin capsules. To overcome this issue you need to choose an HPMC two-piece capsule made from high-quality raw materials and pay close attention to the design of the capsule itself. Look for an HPMC capsule with a strong dome, excellent separation properties, and consistent quality.
Storage and handling conditions
HPMC capsules will tolerate higher levels of heat and humidity than gelatin capsules will. For gelatin two-piece capsules the recommended temperature range is 59°-77° Fahrenheit / 15°-25° Celsius, and the recommended relative humidity is between 35 and 65%. In contrast, HPMC capsules can tolerate temperatures of 59°-86° Fahrenheit / 15°-30° Celsius and relative humidity between 35 and 70%.
Which type of two-piece capsule is best for your product?
While there is no “one size fits all” answer and there are many factors to consider, the vegetarian HPMC capsules are an increasingly popular choice in the nutraceuticals world.