SinodosChemistry

Ethical concerns as well as the vision of pioneer manufacturers to encapsulate plant-based omega 3s into vegan capsules has sparked intense research regarding the development of ‘animal-free’ capsules that would eventually displace, even partially, the soft gelatin capsules which is the industry standard at the moment. The vegan capsules under research aim at providing a cruelty free alternative to existing soft gel capsules but also add value in terms of other features as well, that include bioavailability, handling, safety, compatibility to vegan oils / supplements, thermal and mechanical properties, suitability for consumption, and others.

 

Currently, four categories of vegetarian and vegan capsules exist in the market and in later R&D stages: Hydroxy propyl Methyl Cellulose [HPMC], Pullulan based, Starch based, and Poly Vinyl Alcohol based [PVA]. The features of the four different classes are shown in the table below.

 

Vegeterian Capsule Shell material	Features
Hydroxy propyl methyl cellulose (HPMC)	- Chemically and thermally stable - Moisture content 4-6% less than gelatin capsule (13-16%) - Less brittle even in low humidity - Fast dissolution and H2O soluble - Lower water vapor permeability than gelatin capsule
Pullulan	- Water soluble polysaccharide - odorless, tasteless, and completely biodegradable - Dried capsules are comparatively weak in physical strength. - Relatively low water content (10-15%), than gelatin, low toxicity - High stability of various properties over storage such as mechanical and dissolution properties. - Because pullulan offers the best oxygen barrier of all the plant-based products, these capsules can help mask pungent odors from ingredients and enhance the protection of sensitive ingredients.
Starch	- Made from potato starch - Manufactured by the injection molding technique developed by Capsugel (Capill®) - Suitable for enteric coating - Different size capsules are manufactured (number 0, 1, 2, 3, 4) by changing the mold. - Officially recognized in USP 23 and NF 1
Polyvinyl alcohol (PVA)	- Water soluble - Less hygroscopic than gelatin - Oxygen permeability through PVA copolymer is less than through gelatin and HPMC capsule

 

 

Depending on the intended application of use, the vegan capsules can be a better or a worst match in comparison to existing industry standards like the soft gels and the hard capsules. The decisive parameters include compatibility between the capsule and the contents, structural integrity, environment of use, conditions of manufacture, and others. A simplified general comparison reveals such opportunities and bottlenecks for the use of vegan capsules in the market today:

 

Criteria/ Capsule Type	Gelatin softgels	Hard capsules	HPMC capsules	Pullulan capsules	Starch capsules
Mechanical Strength	+	++	+	+	-
Bioavailability of active	++	+	+	+	+
Resistance to atmospheric moisture	_	+	++	++	+
Resistance to UV radiation	_	-	+	+	-
Resistance to oxygen permeability	++	-	+	++	-
Resistance to heat	_	+	++	++	+
Compatibility with oils	++	-	-	-	-

+: Moderate

-: Low

++: High

 

 

It becomes clear that especially Pullulan capsules hold promise, and their incompatibility with oils is the point that needs bypassing before we, at MVS Pharma and SinodosChemistry are able to offer them to our vegan followers. It is a promise that we will continue to work in this direction, and we will succeed in bringing at least one vegan capsule time to the market soon with our omega 3 supplements.