Collagen Casings

Usage of sausage casings

Sausage casings are raw materials which contain filling of sausages. They may be edible or inedible. In terms of raw materials used, sausage casings may be broadly classified into natural casings and artificial casings. Collagen sausage casing is a kind of artificial casing and is edible.

Characteristics of collagen sausage casings

The primary raw materials for producing edible collagen sausage casing products include dermis of animals. Cattle’s skin is currently in use for production. Collagen casings has the following characteristics:
  • Collagen sausage casings have different lengths, diameters and thickness specifications; they are also well-recognized for their unique texture, high tenacity, distinctive taste and highly consistent product specifications.
  • The uniform shape of collagen sausage casings is suitable for highly automated mass production, and is therefore popular among the sausage manufacturers who emphasize on improving efficiency and expanding capacity.
  • Collagen sausage casings share the properties of food and contain a kind of nutrient consisting of a large amount of amino acid where no harm will be caused after being consumed.
  • Thanks to their consistent quality, collagen sausage casings may be easily extruded as tube or cylinder form for the purpose of packaging, which is convenient for storage and delivery. Collagen sausage casings may be stored and delivered in room temperature without any special treatments and their expiry date is usually two or three years.
Natural casings, casings derived from animals’ haslets, mainly from pigs, cattle, sheep and goats, are the first casing to be used and are traditional packaging materials for meat filling. They are edible, transparent, and heat-shrinkable, and carry high viscosity to meat. However, natural casings have the following defects:
  • Cleansing for animal intestines and heavy processing make mechanization hardly possible and result in high operation cost;
  • The curved shape of animal intestines is unfavorable to the production of sausages;
  • The thickness and tenacity of animal intestines are variable depending on the size of animals and the parts thereof. Such defects hinder the standardization of and mass production of sausages.

Why use collagen

There are certain uncomparable characteristics to use collagen to make casings which cannot be found in other alternative materials:
  • The helical structure and macromolecular crystallization of collagen molecule suggests considerable thermal stability;
  • The impermeable fiber structure of collagen provides collagen materials with high tenacity and strength, which makes it suitable for manufacturing thin-film equipment.
  • During thermal processing, collagen shrinkage is almost consistent with meat shrinkage as water evaporates and fat melts. These properties are not yet found in other edible packaging materials.

Development history and trend of collagen casing products

Collagen sausage casings have almost a century-old history of development. In the 1920s, Germany invented collagen sausage casings which are now widely produced and used in well-developed countries such as the US, Japan, Germany and British. In the 1960s and 1970s, in-depth research was conducted in respect of the film-forming properties of a single piece of collagen or gelatin. After decades of development and enhancement, the quality of collagen sausage casing through industrial production was assured. With a rapid growth momentum, artificial sausage casings replaced most of the natural sausage casings used in different regions and countries like Eastern Europe, North America and Japan. Every company’s own production technology is self developed.

As China’s emphasis on food safety issues increases, more sophisticated production technology emerges and modern facilities and equipment are required for food production and testing, thus speeding up the pace of consolidation in the meat product industry. While some small enterprises will be eliminated, large- and medium-sized sausage manufacturing enterprises will be able to gain more market share. As collagen sausage casings are more suitable for standardization, it is more likely that natural casings will be replaced by collagen sausage casings. It is believed that, gradually, collagen sausage casings will take over more market share from natural casings.