Soft Verses Hard Capsules
Author: Phil Date Posted:10 July 2012
The Melbourne Food Depot sells one type of capsule, in two varieties and many sizes.
(The difference between soft and hard gelatin capsules)
The capsule of choice at The Melbourne Food Depot is the hard style capsule. This hard style of capsule is the only one customers can fill and seal themselves. For ease of explanation I will describe the gelatin manufacturing process. It is exactly the same for vegetable capsules just substitute HPMC for gelatin.
HARD GELATIN CAPSULES
The Manufacture of hard gelatin capsules consists of the dipping of stainless steel pins (dyes) into a gelatin solution, drying, stripping from the pins into a collate, trimming of the caps and bodies, and joining together for shipment. As we supply major manufacturers capsules they have always been supplied joined. A number of requests for separated capsules have been made but not enough to warrant importation and packing in small amounts at this stage. The strength, flexibility and movability of the gelatin allow the manufacture of various sizes, colors and designs for assuring a snap closure after filling. The hard gelatin capsules are NOT suitable for filling with liquid. No consumer level hard capsules are designed to be filled with liquids. The reason why is contained below.
SOFT GELATIN CAPSULES
Soft Gelatin Capsules are not available for sale from the Melbourne Food Depot because this style of capsule is required to be formed, filled and sealed in one continuous motion. This hermetically sealing process is not possible in a domestic setting. The gelatin in this style of capsule is plasticised with propylene glycol, sorbitol or glycerin. The soft gelatin encapsulation process begins with the formation of two ribbons from a molten gelatin, each of which is passed over a die of the desired capsule size and shape. At the point where the two rotating dies meet, the capsule is formed, filled and sealed with the active ingredient. The equipment to produce soft gelatin capsules is far beyond the reach of the home user.
Gelatin or HPMC (vegetable) capsules need to be stored in a dry, cool environment away from light and heat. If the capsules are exposed to strong heat it will cause the the capsule walls to melt and collapse. It is recommended to store them at 20 degrees C when empty and full. When filling capsules it is recommended to wear gloves for two reasons. One to keep your ingredients as clean as possible but the most important is to keep the sweat from your hands away from the hard shells of the capsules. These capsules are designed to dissolve on contact with water.
We hope you now know why we strongly advise not to fill hard gelatin capsules with liquids. They are not designed for this application!