Characteristics and application of hydroxypropylmethylcellulose (HPMC) hollow capsules


In the centuries of capsules, gelatin has maintained it […]

In the centuries of capsules, gelatin has maintained its position as a mainstream capsule with its wide range of sources, stable physicochemical properties and excellent processing properties. With the increasing preference for capsules, hollow capsules are more widely used in the fields of food, medicine and health care products.
However, the occurrence and spread of mad cow disease and foot-and-mouth disease have caused people to start worrying about animal-derived products. The most commonly used raw materials for gelatin are the bones and skins of cattle and pigs, and the risks are gradually being paid attention to. In order to reduce the safety risk of hollow capsule raw materials, industry experts continue to research and develop suitable plant-derived capsules.
In addition, with the increase in the variety of capsules, the diversity of its contents has gradually made people realize that gelatin hollow capsules have compatibility problems with some contents with special properties. For example, content containing an aldehyde group or reacting under certain conditions to form an aldehyde group may lead to cross-linking of gelatin; a highly reductive content may react with gelatin in Maillard (Mailard) Reaction); the moisture-absorbing content will make the capsule shell lose water and lose its original toughness. The stability problem of the above gelatin hollow capsules has attracted more attention for the development of new capsule materials.
Which plant-derived materials are suitable for the production of hollow hard capsules? People have tried a lot. Chinese Patent Application No. 200810061238.X applies sodium sulphate as the main capsule material; 200510013285.3 applies starch or starch composition as the main capsule material; Wang GM[1] reports the manufacture of chitosan capsule raw material. Hollow capsules; Zhang Xiaoju et al [2] reported products containing konjac-soybean protein as the main capsule material. Of course, the most studied is the cellulose material. Among them, hollow capsules made of hydroxypropylmethylcellulose (HPMC) have been formed into a large-scale production.
HPMC is widely used in the field of food and medicine. It is a commonly used pharmaceutical excipient, which is included in the Pharmacopoeia of all countries. FDA and EU approve HPMC as a direct or indirect food additive; GRAS is contained as a safe substance, No. GRN 000213; JECFA database, INS No.464, did not limit the daily amount of HPMC dosage; in 1997, the Ministry of Health approved it as a food additive, thickener (No. 20), suitable for all kinds of food Add [2-9] according to the production requirements. Due to the difference in the nature of gelatin, the prescription of HPMC hollow capsules is more complicated, and it is necessary to add some gelling agents such as gum arabic, carrageenan (seaweed), starch and the like.
HPMC Hollow Capsule is a product with a natural concept. Its material and production process are recognized by the Jewish, Islamic and Vegetarian Associations. It can meet the needs of people of various religious and dietary habits and has a high degree of acceptance.