Gelatine for all Types of Capsules

In pharmaceutical technology, the properties of gelatine such as film formation, thermoreversibility and adhesion are particularly important. The most important application areas for pharmaceutical gelatine are the manufacture of capsules and the embedding of vitamins.

Gelatine capsules are an elegant and widespread pharmaceutical dosage form; they enable drugs to be easily and safely administered whether in liquid, paste or solid form. At the same time, pharmaceuticals in capsule form have a high degree of bioavailability. Pharmaceutical capsules enable active ingredients to be formulated with long shelf lives, protected from light and oxygen. Depending on the nature of the substance to be encapsulated, either hard- or soft capsules can be used. Soft capsules are the more suitable for liquid or paste fillings based on oil whilst hard capsules are used in general for powdered substances.

Hard capsules are made of pure gelatine and have a water content of about 10-15 %. They are generally produced with added dye. They are produced using an immersion process and subsequently supplied to the pharmaceutical industry as closed empty capsules. In a separate process, they are then opened, filled with substance (e.g. powder or granulate) and closed off.

Soft capsules on the other hand are formed, filled and closed off in the one process. The designation soft capsule implies that the outer wall contains, apart from gelatine, a plasticiser, the degree of softness and elasticity of which depends on the quantity and type of plasticiser used, the residual moisture and the thickness of the capsule wall. Soft capsules tend to have thicker walls than hard capsules. Glycerine and sorbitol, or a mixture of both, are normally used as plasticisers. Soft capsules are generally produced using the rotary die method, a process invented by Robert Pauli Scherer towards the end of the 1920s: in this process, two dyed and highly elastic bands of gelatine are passed through rollers. Whilst the capsules are being formed, they are filled with the required active ingredients. Gelatine-coated tablets (caplets) represent a new technical development in this area: using an immersion process, tablets are covered with a gelatine film and subsequently dried. This particular technology enables the economical advantages of tablet manufacture to be combined with the advantages of gelatine capsules for patients. The GELITA Group is the leading company world-wide in the supply of gelatine for all types of capsules.