Gelatin capsules
Gelatin is a substance used in the manufacture of capsule shells using two Gelatin capsule shells in which the medicine is placed and tightly closed together. Gelatin contains collagen (which is extracted from the skin, white connective tissue, and bones of animals). Gelatin also contains On Partial hydrolysis Gelatin (a protein), Gelatin may be either hard or soft.
Types of gelatin available in capsule manufacturing:
1- type A: acid hydrolysis
2- type B: Alkaline hydrolysis
Note: Hydroxypropyl Methylcellulose or starch polymers are examined for capsule preparation.
Gelatin moisture content:
Hard gelatin capsules contain 13% to 16% moisture because a low level of moisture in the gelatin content does not support bacterial growth.
If gelatin capsules are stored in a place with high humidity, it will absorb distorted and lose the shape of the capsules.
However, if the gelatin capsules are stored in a very dry place with low humidity, this leads to lost brittle and crumble when handled.
Therefore, gelatin capsules must be stored in a place free of high humidity or excessive dryness.
The relationship of gelatin capsules with water:
1- Gelatin is insoluble, but it dissolves in cold water.
2- Gelatin is able to absorb water ten times its original volume.
3- Gelatin is soluble in hot water.
4- As for the warm liquid present in the digestive system, it helps the gelatin of the capsules dissolve faster and release the capsule contents.
5- Gelatin, being a protein, is digested by proteolytic enzymes in the digestive system.