What raw materials are best suited for soft capsules? The Complete Guide

Why are oils a staple in soft capsules?

Softgel technology allows hermetic closure of liquid or semi-liquid substances in a one-piece gelatin shell. This method is used primarily for components sensitive to oxidation and requiring precise dosing in oil form. Below we analyze which groups of raw materials show the best compatibility with this manufacturing process.

Substances of a lipophilic nature provide a natural environment for the softgel form, since they do not react with the aqueous base of the gelatin shell. Among the most commonly used components are Omega-3 fatty acids, fat-soluble vitamins (A, D, E, K) and vegetable oils such as evening primrose or borage. The hermetic closure effectively protects these sensitive compounds from the rancidity caused by contact with air. In addition, the liquid form is often characterized by better bioavailability compared to tablet counterparts.

How are suspensions and pastes processed?

In addition to pure oils, this technology allows for encapsulation of suspensions, that is, solid particles dispersed in an oil carrier. This makes it possible to combine mineral components or plant extracts with a fatty base in a single dose. Contract Capsule Manufacturer must take care of the correct viscosity of the mixture to prevent sedimentation, that is, the settling of solid particles to the bottom before closing the mold. This process requires precise homogenization of the batch, which guarantees an even distribution of the active substance in each piece.

When should water resources be avoided?

Soft capsules are incompatible with fillings containing water or hygroscopic substances that can migrate into the shell. The presence of moisture inside the cartridge leads to softening of the gelatin structure, which results in deformation, leakage or sticking of the finished product. If it is necessary to use water components, technologists use special emulsifiers or hydrophilic carriers, such as polyethylene glycol (PEG), which stabilize the system. An alternative is also the use of hard capsules, better suited for loose and dry materials.

The most important information about the production of capsules

Softgel technology is mainly dedicated to liquids, oils and lipophilic suspensions, providing them with protection against external factors. A key limitation of the process is the lack of tolerance to water in the fill, which could damage the shell structure. For solid components requiring suspension in fat, precise viscosity control is necessary to prevent delamination of the mixture. This method guarantees high stability of fat-soluble vitamins and Omega acids, eliminating the risk of their oxidation.

FAQ

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What happens to the capsule after contact with water inside?

Moisture from the filling penetrates into the shell, causing it to gradually dissolve and lose rigidity. This leads to physical damage to the product and leakage of the contents.

What vitamins are best to close in softgel form?

The optimal choice is fat-soluble compounds, i.e. groups A, D, E and K. The oil form promotes their stability and absorption in the body.

Is it possible to enclose powder in a soft capsule?

Direct closure of loose powder is not a standard procedure in this technology. The solid components must be previously dispersed in an oil carrier to form a stable suspension.

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