The manufacture of cooked sausages is a natural adjunct to any meat selling and processing business. Cooked sausages offer an outlet in attractive and palatable form for a variety of raw materials such as edible portions of heads, mutton, pork or beef trimmings, blood, hearts, tripe, livers, lungs, pork stomachs, tongues, various fat materials including those of zebu cattle boss or mutton fat tail as well as other cured or uncured meats that are difficult to dispose of in any other way.
The proper handling and use of edible by-products is of much importance in developing countries where the hygiene standard must be raised. Being highly perishable, edible by-products suffer greatly when there is undue delay between cleaning and processing operations. Every endeavour should be made to have offals carefully handled within the slaughterhouse immediately before they leave the killing floor. The sausage manufacturer may accomplish this in several ways for which speeding up delivery of products to the plant, reducing the number of suppliers and providing facilities for the immediate cleaning and preliminary washing of all by-products in the slaughterhouse seem to be essential.
The trimming of excess fat and inedible connective tissue parts and other operations of by-product pretreatment should take place as soon as possible after slaughter of the animal. If the raw materials are to be chilled before use, this should follow immediately.
Cooked sausages are distinguished from other sausage categories not only on the basis of variety of materials used in their formulations but also by parboiling or partial cooking of most of these raw materials prior to grinding or chopping. The cooking schedules vary with the nature of the raw materials, the age of the animal and the characteristics of the product desired. Some organs, for instance livers, are only scalded.
Raw materials rich in connective tissue, such as heads, are cooked until the meat separates from the bones; the meat obtained is usually chopped very finely in the cutter. The fact that cooking losses from quality lean meats tend to be higher than from poor quality connective tissue-rich meat must be considered.
The ground, usually precooked, raw materials are mixed according to their leanness and fat contents with the corresponding salt quantity, and a portion of broth or water of about 10 percent may be added. After mixing for 3 to 7 minutes manually or in the double-wave mixer, the salt is dissolved and the ingredients are sufficiently homogenized due to the continuous pushing and mixing effect.
Protein emulsifying agents (sodium caseinate or soy protein preparations) are increasingly used in some cooked sausage products. The addition of an emulsifier stabilizes the emulsion and helps in binding the components more firmly together giving the product a firm homogeneous consistency; it contributes also to a more attractive colour and ensures typical spreading properties (see “Sausage raw materials”).
In the production of cooked sausages, it is necessary to use casings having very low moisture vapour transmission and very low oxygen transmission rates. The sausage mix is stuffed into natural or artificial casings. It is obvious that sausage stuffing and linking are very important precooking operations. The occlusion of air in the sausage mix creates pockets or voids which are retained during the following operations. This promotes volumetric and weight nonuniformity in the sausage as well as other undesirable results.
Cooked sausages may or may not be smoked following cooking.
There are numerous cooked meat specialities produced in the same manner as cooked sausages. Many of these specialties are not stuffed into casings but they are shaped in metal or other type containers or moulds. Such cooked items are luncheon meat, head cheese, numerous jellied products etc. Loaves are cooked in moulds and placed in casings or they may be cooked in casings. The cooking is done in a hot water bath but baking in an oven is also applicable.
The following are the formulae and methods of preparation of cooked sausages which have been verified to give satisfactory results.
Liver sausages include many varieties and are made in accordance with widely varying formulae. Liver sausages are basically ground meats, liver and fat to which may be added various cured meats, by-products or nonmeat ingredients, such as spices (Table 6), milk powder, phosphates etc. Not only pork but also beef and mutton livers are excellent raw materials in liver sausage manufacture.
Raw materials used in liver sausage preparations are usually parboiled or cooked before being chopped, mixed and filled into casings. Livers are used either previously cooked or raw. The preparation of livers is of particular importance. Several narrow cuts are made across the liver extremities to facilitate blood and gall extraction. Removal of the bile ducts and large blood vessels is a decisive factor determining the eating quality of the product. There seems to be no difference in processing hot livers immediately after slaughter or chilled ones.
All types of fat can be incorporated in liver sausage emulsions but generally carecass fats are preferred. Internal or body fats, however, can also be processed. Fat material, particularly internal fats, must be washed in cold water, classified according to fat to lean ratio and chilled. Special care should be paid to eliminate factors enhancing oxidative changes.
By-products, including tripe, hearts, backfat, lungs, beef, veal etc. are widely utilized especially in low cost liver sausage formulations. All-beef liver sausages are made with beef and lamb livers. There are trends in reducing the amount of liver and increasing the contents of meat and fat ingredients.
Sausages containing more than 45 percent fatty tissue give a fatty impression in taste and in appearance. Sausages containing 30 to 42 percent of pork jowls or bellies have a pleasant meat-liver aroma. An addition of less than 25 percent of jowls or bellies results in a rough and dry flavour with an acceptable liver aroma. Other body fat tissues should be used at lower levels. The processing of melted pork or beef fat instead of fatty tissue gives the same results: below 20 percent the product is often dry, above 40 percent the fatty appearance and taste become more pronounced.
Present day meat technology and up-to-date equipment used in liver sausage manufacture can guarantee not only a considerable storage life of the final product even in a tropical climate but also surprising economical conditions together with a high quality.
FORMULATIONS
Basic ingredients for 100 kg
40 kg pork liver
60 kg pork belly
55 kg meat trimmings (pork, beef or mutton)
25 kg fat
20 kg liver
(20–30 kg broth - concentrated jellied water in which raw material was cooked)
This formula gives the right percentage of fat, meat and livers to produce a firm mixture with a good spreading quality and rich flavour. A somewhat less firm but still well-spreading product can be obtained by a 10–15 percent increase of fat-to-meat ratio or by adding more broth or water.
40 kg pork liver
30 kg pork bellies
15 kg beef
15 kg cheeks
(jellied water may be added)
20 kg liver
11 kg lean pork
35 kg pork jowls
34 kg bellies
(jellied water may be added)
30 kg liver
10 kg veal
40 kg jowl
20 kg bellies
(jellied water may be added)
25–35 kg veal liver
10–30 kg veal
10–20 kg veal head meats (feet)
10–20 kg beef (mutton) fat
10–20 kg tripe, lungs, hearts
(jellied water added)
In making low cost liver sausages 10–20 percent of the above materials may be substituted by hearts, backfat, lungs, tripe, cooked skins etc.
Characteristic seasoning formulae per 1 kg
Spices for liver sausages should be rigorously selected to give a mildly but delightfully seasoned final product with a distinctive tangy flavour. Liver sausages usually do not contain garlic (see Table 6). Some characteristic seasoning formulae are as follows.
24.0 g curing nitrite salt
3.4 g white pepper
1.3 g coriander
1.2 g mace
0.3 g cloves
0.6 g marjoram
0.2 g thyme
45.0 g peeled onions
If a highly spiced and hot-to-the-palate product is preferred, chili and an increased amount of white pepper may be incorporated in the mixture.
22.0 g curing nitrite salt
0.1 g vanilla
0.5 g allspice
1.2 g marjoram
2.0 g white pepper
0.2 g monosodium glutamate
0.2 g basil
0.5 g mace
40.0 g fresh onion
(This formula is recommended for a beef liver sausage)
20.0 g curing nitrite salt
2.5 g pepper
0.8 g nutmeg
0.1 g vanilla
0.3 g cardamom
0.2 g anise
0.4 g allspice
0.5 g ginger
30.0 g deep-fat-fried onions
18.0 g curing nitrite salt
2.5 g pepper
0.4 g cardamom
0.5 g nutmeg
0.5 g ginger
0.1 g glutamate
2.0 g honey
0.1 g rosemary
30.0 g deep-fat-fried onions
Casings
Various natural or artificial casings of 50–65 mm are used.
Processing and handling
Basically, there are two main processing methods in manufacturing liver sausages: (a) hot processing precooked materials, and (b) cold processing precooked materials. The first method gives a finer, more spreadable product, using often less liver and more by-products. The second method results in a firmer product characterized by a richer liver taste and aroma.
Hot processing of precooked meats and fats
Parboiling of meats and fats. The meats are placed with the peeled onions and about one-third of the prescribed amount of salt in the cooker and cooked at a temperature not exceeding 80°C for 30 to 90 minutes. At the very end of cooking, the fatty tissues are added. To reduce or eliminate mutton or tallow odour, cooking should be sufficiently lengthy. The longer the cooking time, the lesser the amount of retained odour. The meats are normally cooked until they are so tender that the bones can be easily removed.
The broth is left to settle for a while after the meats and fatty tissues have been removed and the grease is skimmed from the top. The broth is then concentrated by boiling, clarified by passing through a cheesecloth and used when still hot (60°C) according to the accepted formula.
Disintegrating and homogenizing liver. Raw livers with one-half of the prescribed amount of salt are comminuted in the cutter until a dark semi-liquid mass is obtained. As soon as air bubbles start to appear, the machine is stopped and the liquid liver is removed from the cutter and kept until used.
Disintegrating, homogenizing and emulsifying liver sausage ingredients in the cutter. The meats after being cooked and the fats scalded are placed together in the cutter bowl and roughly disintegrated using the first speed of the cutter. The second speed of the cutter is then switched on and the remainder of the salt is added until the mass is finely homogenized. If soy or milk proteins are used, the addition of one-half of the prescribed amount should be done at the very beginning and the second half at the end of the operation.
The hot broth, i.e. the water in which the meat and fat were cooked, is added gradually during the operation in such a way that the temperature of the whole mixture is maintained constantly at 58–60°C (final temperature should not be less than 45°C). When thè mass is thoroughly homogenized, the liquefied liver is added and when well distributed usually after 6–8 revolutions of the bowl, the raw liver sausage emulsion is ready. In order to improve the flavour, an amount of deep-fat-fried onion may be added to the mixture during the last cations of the cutter. The raw liver sausage mass may be passed through an emulsifying mill, if desired.
Temperature of emulsion. The temperature of meat ingredients used in processing is a decisive factor in liver sausage production. Meat and fatty tissue must be heated to above 65°C to melt fat and denaturate proteins. Raw livers should be added when the temperature of the meat-fat mixture falls below 60°C to avoid liver protein denaturation but the temperature of the emulsion must not be below 45°C to ensure melting of fat.
Stuffing. When homogenized, the emulsified raw liver sausage mixture is placed in the cylinder of the stuffer. If raw livers are being used, the casings must not be stuffed too tightly because the raw livers expand when cooked.
Cooking and smoking. The products are usually cooked at 80°C for about 60–90 minutes. A point which should be made clear is that high cooking water temperatures may produce jelly pockets in the finished product. Some products are cold smoked for one or more hours.
Storage. After the liver sausages have been cooked and cooled, they are transported to the cold store at 0–4°C.
Cold processing of precooked meats and fats
Alternatively, especially if a firmer higher-value final product is wanted and the amount of liver used is sufficiently large, the cooked meat and scalded fat, after chilling, are placed in the cutter together with other ingredients and thoroughly chopped until a fine emulsion is produced. A good result depends on thorough chilling of precooked material to a temperature below 25°C and the use of a sufficiently potent cutter. All other operations are indentical to those mentioned under (a).
All meat raw materials used in the manufacture of blood sausages, with the exception of fatty tissue and blood, are previously cooked. As their cooking times differ, they have to be cooked separately. Fatty tissues are only scalded and usually diced.
After cooking, the meat materials are coarsely ground and mixed with the other components prescribed in the formulation.
FORMULATIONS
Basic ingredients for 100 kg
25 kg blood
40 kg pork jowls
25 kg pork belly
10 kg skin (veal or pork)
30–60 kg pork skin
25–35 kg pork blood
10–35 kg pork backfat
10–15 kg skin
20–30 kg blood
20–30 kg veal feet (cooked and deboned)
10–15 kg fat or brisket fat
15–20 kg veal or lamb
Characteristic seasoning formulae per 1 kg
22.0 g salt
2.4 g pepper
0.6 g allspice
5.0 g onion
0.5 g cloves
20.0 g salt
2.5 g pepper
30.0 g onion
0.5 g allspice
1.0 g cloves
0.5 g nutmeg or mace
2.5 g marjoram
0.5 g mace
Casings
Beef bungs and middles or corresponding size of artificial casings are used.
Processing and handling
Conventional blood sausage
Pork skin and other kinds of skin, onion and meats are chopped together in the cutter for quite a short time and, after the addition of blood, chopping is continued to produce a fine mass. At the very end of the chopping process scalded diced fat (0.5–1.5 cm) and seasonings are placed in the cutter and evenly distributed in the mix. The cooking of the stuffed product is carried out at 83–85°C for about one hour and quickly chilled.
This blood sausage mix is often used as a matrix or supporting medium in which some other components are added, thus forming an integral part of a new blood sausage variety.
Tongue blood sausage
This blood sausage variety is distinguished by the addition of cured pork, lamb or veal tongues in the blood sausage mix. Casings are loosely filled with blood sausage mix and two or three tongues are inserted lengthwise so that the tongue to blood sausage mix ratio is about 1.2:3.0. Another alternative is to cut the cured tongues into 3 × 4 cm pieces, mix them with the blood sausage mixture and stuff into beef bungs or corresponding size of artificial casings.
Head cheeses are usually defined as cooked meat specialties stuffed and processed in pork stomachs or other natural or large diameter casings in a hot water bath. The composition varies widely but most commonly it includes pork or veal, pork head meats, including skins, snouts, pork underlips, veal feet, tongues etc.
The raw materials are previously cooked to a level dependent upon the nature of each individual component, then ground and/or chopped. The jelly water in which raw materials are cooked is concentrated by boiling and used to improve the flavour, binding properties and value of the final product. Commercial gelatine (1 kg to 8 kg of hot water or according to the specification given by the producer) may be used instead of the cooked water gelatine or instead of the skin.
FORMULATION
Basic ingredients for 100 kg
40 kg pork cheek, feet
20 kg snouts
10 kg underlips
20 kg head skin
10 kg tongue
Characteristic seasoning formula per 1 kg
23.0 g salt
10.0 g onion
3.0 g pepper
2.5 g marjoram
0.5 g allspice
0.5 g cloves
1.5 g caraway seed
Casings
Moisture-proof large diameter casings are used.
Processing and handling
All materials are thoroughly cooked and then chopped and mixed with the seasoning and jelly water remaining from their cooking. The stuffing into pork stomachs or in other types of containers should be loosely done to avoid the product breaking during cooking. Openings in the stomachs are tied and cooking is done at 73–74°C for about 90 minutes. The cooked product is immediately chilled under pressure to allow free water to escape and enhance the binding. Commercial gelatine may be added to facilitate binding.
Blood sausages, liver sausages and head cheeses are often manufactured in loaf forms.
Meat loaves are often attractively arranged, decorated with red or green pepper, pistachio nuts, pickled cucumbers or other types of pickles and packed in characteristic moulds. Basic criteria used to judge the quality of this group of products are the overall appearance of the product, its firmness, delicacy of its flavour, fineness of its manufacture, composition and arrangement of different details, forms and colours as well as professional inventiveness.
