Natural vs Fibrous Sausage Casings — What Is the Difference?

Sausage casings fall into two main categories: natural casings and fibrous casings. Natural casings are made from cleaned animal intestines — hog or sheep — and are edible. They give sausage its traditional bite, snap, and slightly irregular shape that is characteristic of handmade and artisan-style products. Fibrous casings are manufactured from plant-based cellulose fiber and are not edible — they are removed before serving. Fibrous casings are used for large-diameter smoked and cooked sausage products like summer sausage and bologna where shape retention and uniformity are the priority.

Within natural casings, the choice between hog and sheep casings comes down to diameter. Hog casings are larger and are used for full-size sausages like bratwurst, Italian sausage, and smoked sausage. Sheep casings are smaller and are used for thinner products like breakfast sausage links, snack sticks, and hot dogs. Matching the casing size to the product type ensures consistent link diameter, proper stuffing tension, and the right finished appearance.

Natural Hog Casings (32/35 mm) — Bratwurst, Italian Sausage & Fresh Sausage

Natural hog casings in the 32/35 mm diameter range are the standard casing for bratwurst, Italian sausage, fresh pork sausage, and smoked sausage. The 32/35 mm size produces a full-size link with the traditional bite and snap that distinguishes natural casing sausage from products made with synthetic or collagen casings. Hog casings are strong enough to hold up during both hand stuffing and high-speed machine stuffing, and they expand and contract naturally with the product during cooking, which helps the sausage retain moisture and develop a better texture.

Preflushed Hog Casings

Preflushed hog casings have been pre-cleaned and pre-rinsed before packaging, which significantly reduces the preparation time compared to traditional salt-packed casings. They are the right choice for butcher shops and sausage operations that want a natural casing with less handling time at the prep stage. Preflushed casings still need to be soaked in warm water before stuffing to restore full flexibility, but they require less rinsing than unprepared casings. They provide consistent diameter for even links and perform reliably for both hand and machine stuffing applications.

Tubed Hog Casings

Tubed hog casings are pre-loaded onto a plastic tube, which allows them to be transferred directly onto a stuffing horn without the manual threading required for loose casings. This significantly reduces production time in high-volume operations and is the preferred format for commercial butcher shops and meat processors that stuff large quantities of sausage. The tubed format produces more consistent results at speed and reduces the risk of casing tearing during the loading process. For operations prioritizing efficiency over artisan preparation, tubed casings are the practical choice.

Natural Sheep Casings — Breakfast Sausage, Hot Dogs & Snack Sticks

Natural sheep casings are smaller in diameter than hog casings and are used for thinner, smaller-diameter sausage products. Sheep casings are the traditional choice for breakfast sausage links, snack sticks, and hot dogs — products where a narrower diameter and very tender, thin casing wall are important to the finished texture. Sheep casings have a more delicate texture than hog casings and produce a thinner, more tender bite. They are available in two sizes — 20/22 mm and 24/26 mm — each suited to slightly different products.

20/22 mm Sheep Casings — Breakfast Sausage and Snack Sticks

The 20/22 mm sheep casing is the smallest standard size and is used for breakfast sausage links, snack sticks, and other thin small-diameter products. The narrow diameter produces the slim, uniform links associated with breakfast sausage and snack stick products. The 20/22 mm preflushed option comes pre-cleaned for easier preparation and requires soaking in warm water before stuffing. Consistent diameter in this size is important for even cooking — if links vary significantly in thickness, thinner sections overcook while thicker sections remain underdone.

24/26 mm Sheep Casings — Hot Dogs and Fine Smoked Sausage

The 24/26 mm sheep casing is slightly wider and is the standard size for hot dogs, fine smoked sausage, and emulsified sausage products. The additional diameter accommodates the higher moisture content and softer texture of emulsified products without the casing splitting during cooking. Both preflushed and tubed options are available — the tubed version is the better choice for high-volume production where loading speed matters.

Fibrous Casings (2.5" x 20") — Summer Sausage, Bologna & Large Smoked Sausage

Fibrous casings are made from plant-based cellulose fiber and are used for large-diameter smoked and cooked sausage products like summer sausage, bologna, venison sausage logs, and other products where maintaining a consistent cylindrical shape through the cooking and smoking process is the priority. Unlike natural casings, fibrous casings are not edible and are removed before the product is sliced or served. Their primary advantage is structural — fibrous casings hold their shape reliably during long smoking and cooking times, produce a uniform log diameter that makes slicing consistent, and are well-suited for high-yield smokehouse production.

The 2.5 inch x 20 inch size is the standard format for summer sausage and bologna production in butcher shops and commercial processing operations. Fibrous casings should be soaked in warm water for 30 minutes before stuffing to improve flexibility and reduce tearing during the stuffing process. Store unused fibrous casings in a cool, dry place away from moisture to maintain their integrity.

How to Prepare Natural Sausage Casings Before Stuffing

Natural hog and sheep casings require preparation before they can be stuffed. Skipping or rushing the preparation step is the most common cause of casing blowouts, uneven stuffing, and tears during production. The preparation process is straightforward and takes about 30 minutes.

Start by removing the casings from refrigerated storage and rinsing them thoroughly under cool running water to remove any salt from the packaging. Once rinsed, place the casings in a bowl of warm (not hot) water and soak for at least 30 minutes. Warm water restores the flexibility and elasticity of the casing walls, which allows them to stretch evenly during stuffing without tearing. Cold water soaking works but is less effective — warm water is significantly better at restoring full flexibility in the same amount of time.

After soaking, run a small amount of water through the inside of each casing to check for holes and to open the casing for easier loading onto the stuffing horn. Casings with small holes can sometimes still be used for coarser products where the hole can be tied off, but casings with multiple holes or significant tears should be discarded to avoid blowouts during stuffing.

For a full step-by-step preparation walkthrough, see the CutleryMania guide to prepping natural casings.

Preflushed vs Tubed Casings — Which Should You Choose?

Both preflushed and tubed casings are natural casings of the same quality — the difference is in how they are packaged and how they are loaded for stuffing. Preflushed casings are packaged loosely and need to be manually threaded onto the stuffing horn before use. Tubed casings come pre-loaded on a plastic tube that can be transferred directly onto the stuffing horn, eliminating the threading step entirely.

For home sausage makers and small-batch operations, preflushed casings are the standard choice — they are slightly more economical and the manual threading process is not a significant time burden at low volumes. For commercial butcher shops and operations stuffing large quantities of sausage, tubed casings are the more efficient option. The time saved on loading each batch adds up significantly over a full production day, and the consistent loading tension produced by the tube format also reduces variability in link diameter and casing wall integrity.

Quick Sausage Casing Selection Guide

Frequently Asked Questions — Sausage Casings

What are natural sausage casings made from?

Natural sausage casings are made from cleaned animal intestines — either hog (pork) or sheep intestines. The intestines are thoroughly cleaned, flushed, and graded by diameter before packaging. Natural casings are edible and give sausage its traditional bite, snap, and slightly irregular appearance that distinguishes hand-crafted sausage from products made with synthetic or collagen casings.

What size casings are best for bratwurst?

32/35 mm natural hog casings are the standard choice for bratwurst and Italian sausage. The 32/35 mm diameter produces the traditional full-size link associated with these sausage styles and provides the classic natural casing snap and bite that cannot be replicated with collagen or synthetic casings.

What casings are used for hot dogs?

24/26 mm sheep casings are the traditional choice for hot dogs and fine emulsified sausage products. The 24/26 mm diameter produces the slim, uniform shape associated with hot dogs, and the thin sheep casing wall provides the characteristic tender snap when bitten.

What are fibrous casings used for?

Fibrous casings are used for large-diameter smoked and cooked sausage products like summer sausage, bologna, and venison sausage logs. They maintain a consistent cylindrical shape during long smoking and cooking times and produce a uniform log diameter that makes slicing consistent. Fibrous casings are not edible and must be removed before the product is sliced or served.

Do I need to soak sausage casings before using them?

Yes — natural hog and sheep casings must be soaked in warm water for at least 30 minutes before stuffing. Soaking restores the flexibility and elasticity of the casing wall, which allows it to stretch evenly during stuffing without tearing. Casings that are not soaked properly are more prone to blowouts and uneven stuffing. Fibrous casings should also be soaked in warm water for about 30 minutes before use.

What is the difference between hog casings and sheep casings?

Hog casings are larger in diameter (32/35 mm) and are used for full-size sausage products like bratwurst, Italian sausage, and smoked sausage. Sheep casings are smaller (20/22 mm or 24/26 mm) and are used for thinner products like breakfast sausage, snack sticks, and hot dogs. Sheep casings also have a more delicate, thinner casing wall that produces a more tender bite than hog casings.

What is the difference between preflushed and tubed casings?

Preflushed casings are packaged loosely and need to be manually threaded onto the stuffing horn before use. Tubed casings are pre-loaded on a plastic tube that transfers directly onto the stuffing horn, eliminating the threading step. For home use and small batches, preflushed is the standard choice. For high-volume commercial production, tubed casings save significant time and reduce variability in the stuffing process.

Can fibrous casings be eaten?

No. Fibrous casings are made from plant-based cellulose fiber and are not edible. They are designed to be removed before the sausage is sliced or served. Products like summer sausage and bologna made with fibrous casings are always peeled before consumption.

Why do my sausage casings burst during stuffing?

Casing blowouts during stuffing are most commonly caused by under-soaking (casings that are not flexible enough before stuffing), overstuffing (filling too tightly so the casing cannot expand), stuffing too fast without allowing the casing to stretch gradually, using a funnel that is too large for the casing diameter, or casings with pre-existing holes or weak spots. Soak casings in warm water for the full 30 minutes, stuff at moderate speed, and leave a small amount of slack in the casing to allow for expansion during twisting and cooking.

How should I store sausage casings?

Natural hog and sheep casings should be kept refrigerated. They are typically packed in salt, which preserves them, and will keep for an extended period under refrigeration. Do not freeze natural casings as this damages the casing wall. Fibrous casings should be stored in a cool, dry place away from moisture and do not require refrigeration before use.

What funnel size should I use with these casings?

Match the stuffing funnel diameter to the casing size. For 32/35 mm hog casings, use a medium funnel (approximately 22–26 mm). For 20/22 mm sheep casings, use a small funnel (approximately 16–20 mm). For 24/26 mm sheep casings, use a small to medium funnel (approximately 18–22 mm). For 2.5 inch fibrous casings, use a large funnel. CutleryMania carries a stainless steel stuffing funnel set in small, medium, and large sizes that covers all standard casing diameters.

Shop Sausage Casings

CutleryMania carries natural hog casings, natural sheep casings, and fibrous casings in preflushed and tubed options for commercial and home sausage production.

• Natural Hog Casings 32/35 mm — Preflushed — Bratwurst, Italian sausage, fresh pork sausage
• Natural Hog Casings 32/35 mm — Tubed — High-volume commercial stuffing
• Natural Sheep Casings 20/22 mm — Preflushed — Breakfast sausage and snack sticks
• Natural Sheep Casings 24/26 mm — Preflushed — Hot dogs and fine smoked sausage
• Natural Sheep Casings 24/26 mm — Tubed — High-volume commercial stuffing
• Fibrous Casings 2.5" x 20" — Summer sausage, bologna, venison sausage logs
• How to Prep Natural Casings — Step-by-step preparation guide

Also useful for sausage making: Stainless Steel Stuffing Funnels | Grinder Plates for Sausage Texture | Boning Knives

Questions? Call or text CutleryMania at (973) 287-6535 or email sales@cutlerymania.com. We respond within one hour during business hours.