Chapter 4

Sausage Casings

Topics Covered• Natural casings• Synthetic or cellulose casing• Collagen casing• Stuffing the casing• Smoking the sausage• Poaching the sausage

Natural Casings• Processed intestines of hogs, sheep, and

cattle– Hog stomach: tongue sausage– Sheep stomach: haggis (Scottish specialty)– Beef: middles and rounds

• For bologna, mortadella, liverwurst, salami, etc.– Beef bung: veal sausage, large bologna and

cooked salami

Natural Casings (cont’d.)• After harvested, intestines are:– Cleaned– Calibrated – Stretched and sized – Packed in plain salt or a salt brine solution• Measurements– Large intestine casings in inches– Smaller intestine casings in millimeters

• Called hank or bundle

Natural Casings (cont’d.)• Before use:

– Wash in lukewarm water– Force water through to

flush out impurities – Rinse outside to remove all

salt– Soak for one hour in warm

water to soften and make tender One hank of sausage casings

Natural Casings (cont’d.)

Beef casings

Natural Casings (cont’d.)

Lamb casings

Natural Casings (cont’d.)

Hog casings

Synthetic or Cellulose Casings• Synthetic fibrous casings:

– The norm– Array of colors– Purchased on Internet or mail-order– Usually lined on inside with a coat of protein

• Allows synthetic casing to shrink with filling– Less expensive– Easier to store– Synthetic/cellulose casings are not edible

Collagen Casings• Similar to animal casings but have

manufactured uniformity– Allow consistency– Hide of cattle consists of collagen– Corium layer is extruded from area between

grain (hair) layer and fat and muscle layer– Protein and water are mixed with lactic acid

and cellulose fibers, causing swelling and slurry to form

Collagen Casings (cont’d.)• Acid-swollen slurry is de-aerated under

vacuum – Homogenized and filtered– De-aerated again; stored to chill in tanks– Extruded through die with counterrotating

sleeves: “weaves” fibers together– Passes through concentrate coagulating

solution of inorganic salt

Collagen Casings (cont’d.)• Chemically treated in processing machine

– Cross-link • Washed, plasticized with glycerin, dried,

and partially rehumidified and wound on reels– Reels are taken to a shirring machine – Collagen casing is shirred to regenerate

cellulose

Collagen Casings (cont’d.)• Two types of edible collagen casings:

– Thin skin for fresh sausages– Thicker skin for smoked sausages

• Nonedible flat collagen casings:– Can be stored at room temperature– Must be soaked in salted lukewarm water for

30 minutes before use

Stuffing the Casing• Set up hand or electric sausage

– Make sure nozzle and work table/sheet pan are lubricated with cold water

• Prevents sticking and tearing– All parts of stuffer that contacts forcemeat

must be sanitized, clean, and well chilled– Fill stuffer with forcemeat by pressing or

tapping down • Removes all possible air pockets

Stuffing the Casing (cont’d.)• Slide open end of casing

over nozzle – Pipe into casing– Support casing with full hand

as forcemeat is piped into nozzle casing

• After sausages are measured into shape, pierce to remove air pockets

Filling hog casing for boudin and readycooked boudin

Stuffing the Casing (cont’d.)

Making a bubble knot for large casings

Smoking the Sausage• Cold smoke:

– Hang sausages made without curing salts to dry for 1 to 2 hours in a 70°F room

• Hot smoke: – Hang cured sausages to incubate in a 70°F

room for 12 to 24 hours – Smoke following time and temperature

directions – Sausages are now ready to be poached

Poaching the Sausage• Use a large or oversized pot• Use hand or digital thermometer to

monitor temperature of poaching water – If water temperature is too high, sausages will

burst• If too low, the sausages may lose flavor

– Starting temperature: 160°F–170°F – Finishing internal temperature: 155°F to

160°F

Poaching the Sausage (cont’d.)• Cooling process for natural casings is

started in cold running water• For synthetic casings, start cooling in

lukewarm water – Slowly finish in cold running water

• All sausages must be refrigerated or frozen before use

Summary• This chapter reviewed:

– Differences among various casings (natural, synthetic, and collagen)

– How to work with casings– How to prepare casings for filling– How to tie casings– How to poach and cool sausages