Natural vs Collagen Sausage Casings: Which to Use
By the Claasens team, makers of South African sausage fillers since 1955.
The casing is the skin of the sausage. It holds the mince together, it gives the sausage its shape, and it provides the snap that boerewors lovers know and love. The wrong casing will leave you with a sausage that bursts on the braai or chews like a rubber band. The right one will disappear into the wors and let the meat do its work.
This guide covers every casing you are likely to encounter in South Africa, what each is good for, and where to buy them. It is the conversation we have with customers who ring up uncertain what to put on their sausage filler.
Natural casings
Natural casings are made from the cleaned intestines of sheep, pigs, or cattle. They have been used for sausage-making for thousands of years and are still what serious butchers reach for first.
Sheep casing
The thinnest of the natural casings. Sold in diameters from 18 to 28 mm. The classic choice for boerewors, frankfurters, and droëwors. The casing is delicate, almost translucent, and disappears into a clean snap when grilled. The traditional South African boerewors casing is sheep, 26 to 28 mm.
Pros. Best snap, best bite, most traditional, lightest casing presence.
Cons. Delicate. Tears easily when filling if you rush. Requires careful soaking and rinsing.
Hog casing
Pig intestine. Thicker, more robust, sold in 32 to 38 mm diameters. The casing for bratwurst, Italian sausage, thick farm-style boerewors, and anything that needs to take a longer grill without bursting.
Pros. Strong, forgiving when filling, holds shape on the braai, easier for beginners.
Cons. Chewier than sheep. Slightly less elegant snap. Heavier casing presence.
Beef casing
The thickest natural casing, used for salamis, chorizo, and air-dried sausages. Rarely used for fresh wors because the bite is too tough. Useful for droëwors made in a thicker style, especially game droëwors that benefits from a heavier wrap.
Pros. Excellent for dried and cured sausages. Holds shape during long drying.
Cons. Very chewy when fresh. Not suitable for braai-fresh wors.
Collagen casings
Collagen casings are made from processed beef or pork hide. They look like clear plastic tubes but are fully edible and digest in the same way as natural casings. Modern collagen casings have become remarkably close to natural in texture.
Edible collagen
The everyday collagen casing. Available in any diameter, very uniform thickness, almost no preparation needed (most are ready to use straight from the pack). The default casing for commercial South African retail wors because consistency matters when you are packing 50 kg an hour.
Pros. Uniform, beginner friendly, long shelf life, no soaking or rinsing.
Cons. Slightly tougher snap than sheep. Less traditional.
Inedible collagen
For dried sausages where the casing is removed before eating. Salamis, chorizos, dried hams. Not relevant for boerewors or droëwors.
Which casing for which sausage?
| Sausage | Casing | Size |
|---|---|---|
| Traditional boerewors coil | Sheep | 26 to 28 mm |
| Thick farm boerewors | Hog | 32 to 38 mm |
| Droëwors | Sheep (thin) | 22 to 24 mm |
| Salami / air dried | Beef or inedible collagen | 50 to 75 mm |
| Frankfurter / hot dog | Sheep or edible collagen | 22 to 26 mm |
| Bratwurst / Italian | Hog | 32 mm |
| Retail uniform wors | Edible collagen | 26 to 28 mm |
How casings are sold
Salted natural casings are sold in bundles called "hanks". A hank of sheep casing is typically 90 metres long, which fills roughly 25 to 30 kg of meat. A hank of hog casing is about 30 metres long, filling 20 to 25 kg. Collagen casings are sold by the metre or by the strand.
For most home users, half a hank of sheep casing lasts a year of weekend wors-making.
Storage
Salted natural casings keep in the fridge for a year if stored properly. Drain the casings well after rinsing. Pack them in a sealed container, cover them with coarse salt, and refrigerate. Replace the salt if it gets wet. Keep them cool, dry, and salted, and they will be ready next time you need them.
Collagen casings keep at room temperature in their original packaging for 2 years.
Where to buy casings in South Africa
- Independent butchers. Most will sell you a hank or a half hank if you ask. Bring your own sealed container.
- Online sausage supply stores. Several South African sausage supply businesses ship countrywide. Search for "sheep casing South Africa" and choose a supplier with good reviews.
- Farmer's markets and game butchers. Often the best source for hog casing during hunting season.
Preparing natural casings
The single biggest mistake home wors makers make is not preparing the casings properly. Skip these steps and you will have salty, leaky, tearing wors.
- Soak. Drop the casing bundle in a bowl of cool water for at least one hour. Two is better. Sheep casings need more soaking than hog.
- Rinse outside. Run cool water over the outside to remove surface salt.
- Rinse inside. Slide the open end of each casing onto the kitchen tap and let cool water flow through. The casing balloons up. Let the water flow out the other end.
- Keep wet. Drop the rinsed casings back into cool water until you use them.
For full filling instructions, see our sausage filler how-to.
FAQ
Are collagen casings as good as natural?
For most home wors, yes. The snap is slightly tougher and the eating experience is slightly less elegant, but the convenience makes them an excellent choice for beginners and high-volume retail.
What casing should I use for traditional boerewors?
Sheep, 26 to 28 mm. It is the most traditional and gives the classic boerewors snap.
Can I freeze sausage casings?
Salted natural casings can be frozen but it is not necessary, because they keep in salt in the fridge for a year. If you freeze them, thaw in the fridge overnight before soaking.
Why do my casings smell strange?
Natural casings have a faint, slightly metallic smell when first soaked. This is normal and rinses out. If the smell is strongly off, the casings have spoiled and should be discarded.
How long does a hank of sheep casing last?
About 90 metres of casing fills 25 to 30 kg of mince. For a household making weekend wors, that is a year of supply.
Can vegetarians eat collagen casings?
No. Collagen casings are made from animal connective tissue, usually beef or pork hide. They are not vegan or vegetarian.
About Claasens
The Claasens family has been making sausage fillers in South Africa since 1955. Whatever casing you choose, our leverage and geared sausage fillers, paired with our funnel set, handle every casing diameter from 22 mm sheep to 38 mm hog. If you have a question that is not answered above, our workshop is a phone call away.