Manufacturing of meat sausage: Filling

Prior to filling the casings, it is important to eliminate oxygen from the mixture using vacuum-filling devices, and the temperature of the mix should not exceed 2°C.

When filling sausages, the two primary objectives are to ensure precise portioning and to remove any air pockets from the product. The removal of air enhances the color stability and visual appeal of the sausages.

Sausages can be filled with a soft, less compact, or compact consistency depending on the specific requirements of the producer.

There are two main types of sausage casings: natural and synthetic. Natural casings are derived from the digestive tracts of animals, such as sheep (3/4-inch in diameter), hog (1-3/8 inches), and cattle (1-3/8 inches) intestines. Natural casings, sourced from the intestines of animals, are commonly used, along with casings made from modified collagen or cellulose.

Traditionally, sausages are stuffed into natural casings obtained from animal intestines, but artificial casings are also available in the market. Nowadays, synthetic casings are predominantly used in most commercial sausages.

Fresh sausages can also be filled into small-diameter synthetic or artificial casings, or they can be extruded into short, large-diameter plastic casings known as "chub" packs, typically containing 1 to 2 pounds of meat. Fibrous casings are more suitable for summer sausage and similar products due to their superior strength and the variety of sizes they offer. These casings allow smoke and moisture to permeate the sausages and can be easily removed from the finished product.
Manufacturing of meat sausage: Filling

Manufacturing of meat sausage: Grinding and mincing

Of all the various processed meats, sausage is the most appetizing and widely utilized. The word “sausage” is derived from the Latin word salsus, which means salted.

Grinding
Before grinding, it is important to trim the meat of glands and sinew. Although the process of “cleaning” the meat of these items makes more work, it will help produce a better sausage.

The screw is the main working part of the grinder. It steadily pushes meat down the shaft and toward the blades. The blade and plate are what do the actual grinding. The key to doing a good job grinding is to use sharp blades and plates that match. The blade is a small, cross-shaped piece with a sharp edge on each arm that rotates against the plate (also called the die).

The sausage may be ground twice, especially if two meats, such as a fat meat and a lean meat, are being used. The fist-size chunks of lean meats are first ground by running them through a 3-6 mm grinder plate while fat trimmings or fatty tissues are reduced through a 6-9 mm grinder plate. Grinding improves the uniformity of the product by distributing the ingredients and making the particles the same size.

Ideally, meat should always be chilled between 0-2ºC for a clean cut. Since refrigerator temperatures are roughly 3-4º C, meat should be placed in a freezer for about 30 min just before grinding.

Mincing
After grinding, the meat is minced in to a very fine particle size for easy protein extraction. Proteins have the function of binding the water surrounding fat droplets and keeping them dispersed.

Mincing mechanically disrupts these protein structures and enhances the sensory tenderness of the finished product. The disruption of cellular membranes allows a rapid distribution throughout the meat particles of subsequently added salt (usually around 1% of the meat weight in a mince or a hamburger patty) or other spices, flavors, or additives for fresh sausage manufacturing.

The time of mincing, the lean meat should be chopped for a sufficient period, normally not less than 6-8 minutes. Chopping is then continued until the batch is thoroughly chopped.
Manufacturing of meat sausage: Grinding and mincing

Manufacturing of meat sausage: Ingredients and processing

Sausage is a food product resulting from the assemblage of proper ingredient in the right proportion coupled with a structured design and controlled process. The quality of the product is always a reflection of the status of the raw materials and the process. Its taste, texture, tenderness and color are related to the ratio of fat to lean.

Fresh sausage is typically prepared from one or more kinds of meats. It may contain water (not exceeding 3 percent of the total ingredients in the product) and binders and extenders (for example, wheat flour and non-fat dry milk).

Good sausage begins with good meat. Beef, veal, pork, lamb, mutton, and poultry are all suitable for use in sausage. A majority of sausage products are prepared with pork and beef. Meat should be fresh, high quality, have the proper lean-to-fat ratio and have good binding qualities. The meat should be clean and not contaminated with bacteria or other microorganisms.

Other ingredients such as salt (addition to taste, extract some proteins from meat, enhances flavor, reduce microbiological spoilage and increases water holding), water ice (assist the process of mixing and help salt to solubilize meat proteins), curing agents (inhibit microbial growth, provide pink color and enhance flavor), spices (add flavor to the product) and binder (promote fat and moisture retention) and extender (reduce formulation costs).

The basic steps in sausage making are:
• Weighing/measuring the ingredients
• Grinding
• Stuffing/linking
• Smoking/cooking

Sausage making has become a unique blend of old procedures and new scientific, highly-mech-anized processes. Traditionally, sausage was formed into a symmetrical shape, but it now can be found in a variety of shapes and sizes to meet consumers’ needs.
Manufacturing of meat sausage: Ingredients and processing