Capsules continue to be a favorite dosage delivery form. Among supplement users, 42% prefer capsules, according to the 2015 Supplement/OTC/Rx Database (SORD) study. They are portable, convenient, clean, and easy to swallow. Enthusiasts also are motivated by lifestyle values, and capsules can deliver on the clean label promise, offering vegetarian and organic options.

Today, supplement users are increasingly expressing their desire to know that a supplement has a chance of being effective via nutrient integrity, absorption, and sheer palatability that supports consumption, according to the SORD study. To speak to those consumer concerns, supplement manufacturers can look to capsules and keep abreast of the ever-changing and inventive technologies.

Here are four of the most recent cutting-edge technologies for hard capsules. They solve unique delivery challenges to optimize intake and outcomes of specific ingredients while also remaining true to the clean-label promise.

Pullulan Capsules for Liquids 
Soft gels and hard gelatin capsules have often been the standard delivery forms for pungent nutritional oils, most notably fish and krill oils. Manufacturers of the former might add fragrances or flavors to mask the odors that emanate from the shell due to the micro-channels created by the soft gel’s plasticizers. Hard gelatin capsules—especially those nitrogen-flushed upon filling and then hermetically sealed to prevent oxidation—can more successfully block smells. Hard capsules come in fish, bovine, and porcine gelatin, as well as vegetarian polymers—all without plasticizers. 

Recently, a more natural alternative for “stinky” oils has been introduced with exceptional odor barrier properties. This vegetarian pullulan capsule, naturally fermented from tapioca, has the highest odor barrier properties of all polymers, better than gelatin or HPMC capsules. The pullulan capsule is Non-GMO Project Verified and has a moisture content similar to gelatin. For powders, it is an ideal carrier for vitamin C because it withstands the Maillard reaction. Now introduced for liquids, it provides excellent oxygen protection for ingredients prone to oxidation and gelatin-like odor protection. It is eligible for the “Made with Organic Ingredients” listing on the label. 

This is achieved without the use of additives, helping to further solidify its appeal to hardcore organic and clean-label consumers while attracting buyers in the growing healthy aging and nutritional oils market segments—especially those looking for an all-vegetarian product.

Acid-Resistant Polymer Without Enteric Coating
Enteric coatings have long been applied to tablets, capsules, pellets, and granules (filled in capsule shells) to delay release of ingredients into the upper intestinal tract. They protect the ingredient from being compromised and weakened by gastric acids and/or target delivery of the ingredient to the intestines where they would work best. The coatings can be made of fatty acids, waxes, shellac, plastics, plant fibers, and film resins. 

Now there is a capsule that offers an alternative for enteric coatings. This vegetarian capsule offers unique inherent acid-resistant polymer properties so the capsule resists disintegration in the stomach but opens immediately once the pH rises above 6.8—out of the acidic environment of the stomach. A clinical study of the capsules with eight human subjects confirmed that the capsules exhibited delayed-release properties. Disintegration started about 52 minutes after ingesting the capsule. For most of the subjects, complete release took place in the small intestine around 20 minutes after the onset of release when the pH shifted more to a neutral pH of 5.8. These results proved that the capsule is clearly acid-resistant and delivers to the small intestine.

Because the capsule is made of low-moisture hydroxypropyl methylcellulose (HPMC), it also can keep moisture-sensitive ingredients stable in the package before ingestion and protect from acid after ingestion—well suited for delivery of probiotics, enzymes, and many sports nutrition ingredients. 

Lipid Multi-Particulate Technology
A new microencapsulation technology called Lipid Multi-Particulates (LMP) has repurposed a long-standing multi-active time-release concept from the pharmaceutical industry for health and nutrition. 

LMPs are spherical in shape and are characterized as microspheres. Each particle is formulated to contain a measured micro-dose of active nutritional ingredients including botanicals, vitamins, and amino acids. Particle sizes range from 50 to 300 microns. The ability to precisely deliver a metered dose of actives combined with controlled particle size of LMP can lead to improved gut distribution. They also feel smooth in the mouth rather than crunchy to the teeth. The combination of size and specific formulation can affect the timing of the controlled dissolution after ingestion. 

The primary rationale for LMPs is taste-masking of ingredients like teacrine or phosphatidic acid. But it can also be used to develop timed release of ingredients such as caffeine or CoQ10. Because LMP microspheres have excellent flow properties, they work in a broad range of finished dose formats, including textured powder blends via sachets and sticks for reconstitution in liquids, powder-filled capsules, liquid-filled capsules, sprinkle capsules, capsules-within-capsules, and even compressed in tablets.  

Improved ‘Sprinkle’ Capsules
Approximately 26% of consumers have a hard time swallowing pills, especially infants, young children, and the elderly. “Sprinkle” capsules—with contents of powders and/or multi-particulates, or bead formulations if the powders have a strong flavor or taste—allow for oral administration by simply opening the capsule and sprinkling the contents onto soft food. 

An improved version of the standard capsule for sprinkled contents has been created with reduced locking force to make it five times easier to re-open than a standard capsule that requires sufficient grip strength and dexterity. A consumer panel of 37 (parents of young children, nurses, and unimpaired adults 65 and older) tested the performance of the improved sprinkle capsules and traditional standard prefilled capsules. Results showed 81% found the improved sprinkle capsule “very easy” or “easy” to open, compared to 29% favoring the standard capsule opening.

The ingenious locking-unlocking mechanics functions well without separation or loss of content as was proven in a transportation study. After normal filling, packaging, and shipping to a final destination, the capsules showed zero loss of pieces or opening.

Capsules as a dosage delivery form are versatile and ever changing. For every delivery challenge, there is an answer, be it for an ingredient or a consumer group. The latest technologies attest to that.