Commercially used collagen casings are more commonly used and considered to be a much affordable option as compared to natural casings. However, these collagen casings are made of hides of pigs and cows. Apart from that, bones and animal tendons are also used in making these casings.
Secondly, the Cellulose casings are made of viscose, which is basically a component extracted from the wood pulp or cotton linters (these are basically fibers that stick to the cotton seeds after being separated from the cotton). These casings are strong and sheer. Apart from that, these casing may peel off as you cook them. Lastly, the plastic casings are not edible and are easily impermeable; Thus they can not be smoked.
In some cases, artificial casing can be used only after soaking in lukewarm water and need to be opened with a knife to eliminate air pockets before stuffing them with ground meat. The good thing about synthetic casings is their symmetry in shapes and textures which remains the same.
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