Most capsules are made of gelatin. Gelatin is widely used in many foods, such as puddings, sweets, preserves, chewing candies, icing, whipped cream toppings, dips, etc. In food applications, gelatin can gel, thicken, stabilize, and ventilate. It is a very popular, nutritious and fat-free ingredient. Because of its hypoallergenic and water-absorbing properties, gelatin has also been widely used in many daily necessities, such as cosmetics and toiletries. Gelatin is a water-soluble protein extracted from collagen, and collagen is the main natural protein component in connective tissue. After processing animal skins and bones according to a controlled extraction process, gelatin can be extracted from its collagen. There are many types of gelatin. The capsules are made of pharmaceutical-grade gelatin, which meets the stringent requirements of the United States Pharmacopeia and other international agencies that set standards for materials needed in the production of pharmaceuticals.
In addition to gelatin, capsules can also use non-animal-derived materials as raw materials to meet the special requirements of a variety of cultures and diets, including vegetarians and diet-restricted patients. Pullulan and hypromellose are two non-animal-derived capsule materials. Pullulan is a water-soluble polysaccharide produced by fermentation, and its safety has been widely recognized by regulatory agencies in various countries. It has been used in commercial production for more than 25 years and is widely used in the food and pharmaceutical industries. Hypromellose (HPMC) is extracted from cellulose raw materials and is widely used worldwide.
In the process of producing capsules, gelatin, pullulan and hypromellose are all formed into a film on the stainless steel mold needle. The gel film on the mold needle will gradually harden after drying, and finally form a capsule, which is then removed from the needle. Normally, two different sizes of mold needles are used; one is used for the capsule body, and the other is used for the cap of a two-section capsule with a larger diameter. The capsules are then loaded into the capsule filling machine, which fills the capsules with powder, liquid or paste.