Emulsified sausages are cooked sausages that have been finely comminuted to the consistency of a fine paste. Hot dog, frankfurter, mortadella, bologna, liver sausage, pâté are typical examples. In most cases they are smoked and cooked with moist heat (steamed or in hot water). The first emulsified sausage was probably the German frankfurter, followed by the Austrian wiener. In the 1800’s German immigrants brought these recipes to America and originally these sausages were served like any other. The story goes that in 1904, a street vendor in St.Louis was selling his wieners on small buns. They were nicknamed the “red hots” as they were too hot to handle by his customers. Suddenly he got this great idea of making a bun that will fit the shape of the sausage and an all American favorite “hot dog” was born.
Emulsified sausages can be divided in two groups:
- High quality products made at home such as Austrian wiener or Polish Serdelki which are made from high quality meats and without chemicals. Beef, veal and pork are the meats commonly used. Beef frankfurter contains beef only. High quality products contain enough lean meat to absorb the necessary water without help from water retention agents.
- Commercial products made from all types of meat trimmings (pork, beef, chicken, turkey), including machine separated meat. Chicken hot dogs, turkey hot dogs and all possible combinations can be found in a supermarket. A large number of chemicals, water binding agents, fats and water are added during manufacturing to compensate for lower meat grades.
The public prefers moist emulsified sausages and it is hard to imagine a hot dog or frankfurter that will feel dry. In commercial production meat is chopped in bowl cutters by rapidly moving blades which creates lots of friction. This action develops a significant amount of heat which will encourage the growth of bacteria. To prevent that, the manufacturer adds crushed ice to the meat in the chopper.
Emulsification will be successful if the following criteria are met:
- Enough lean meat has been selected. The lean meat is the main source of myosin. The more myosin extracted, the thicker and stronger protein coat develops around particles of fat.
- Enough myosin has been extracted. This depends on how vigorous the cutting process was and how much salt (and phosphates) was added.
Too much fat, especially when finely comminuted, will create such a large surface area that there will not be enough protein solution to coat all fat particles. As a result pockets of fat will form inside of the sausage. Some moisture is lost during smoking, cooking, and storing, and this factor must be allowed for in the manufacturing process. To make up for those losses more water is added during chopping/emulsifying. Experienced sausage makers know that the meats used in the manufacturing of sausages exhibit different abilities at holding water. Lean meat can hold more water than fatty tissue. Organ meats such as heart, glands, pork and beef tripe, pork skin, or snout all have poor water holding capabilities. Red meat found in pork head exhibits good water holding capability. Generally speaking any lean red meat holds water well although beef is on top of the list.
- Beef - high
- Veal - medium
- Pork - medium
Beef meat can absorb significant amounts of water:
- Bull meat - up to 100%
- Shank meat - up to 70%
- Cow meat - up to 60%
- Cheek meat - up to 40%
In simple terms 100 lbs. of cow meat can absorb 60 lbs. of water and 100 lbs. of bull meat can absorb 100 lbs. of water. An average beef piece bought in a local supermarket should hold about 30-40% of added water. To make top quality emulsified sausages at home a combination of lean red muscle meats should be used. This does not mean that only best lean cuts of meat must be employed. Using meat trimmings is in fact encouraged. A typical frankfurter recipe consists of about 60% beef and 40% pork trimmings. Those trimmings may consist of cheaper grades of meat such as heart, cheek meat, pork or beef tripe, and fats. As long as lean beef is used to bind water, other “filler” meats may be added.
A commercial manufacturer can not afford the luxury of using only top quality meats and to keep the costs down he has to use second grade meat trimmings. Keep in mind that there is nothing wrong with such meats from a nutritional point of view, but in order to successfully incorporate them in a sausage we have to resort to water binding agents which will help to absorb and hold water within the meat structure. If you study some original instructions for making emulsified sausages from earlier times when chemicals were not yet widely used, you will see that beef was always ground with a smaller plate than pork. This was done in order to fully extract meat proteins which allowed meat to absorb more water.
As finer meat particles are obtained, more protein is extracted and more water can be absorbed by the meat. The fats are not going to hold water and it makes little sense to emulsify them as fine as lean meat. That is why fat is added to the bowl cutter at the end. If show meats (larger pieces) or chunks of fat (Mortadella) are required, they will be mixed with an emulsified sausage mass in a mixer.
Water plays an important part:
- It helps to extract water soluble proteins (actin and myosin) which contribute to better meat binding and strong emulsion.
- It helps to keep temperature down by adding ice to the bowl cutter.
- Lean beef, veal, lean pork. Keep in mind that the color of the sausage will depend on the type of meat used (myoglobin content) and to a smaller degree on spices.
About 20% of fat is needed for good texture, taste and flavor. Hard and soft fats can be used. Pork fat, beef fat, mutton fat, chicken fat or even vegetable oils can be utilized. Beef and lamb fat have a very strong flavor which can be masked by a careful choice of spices. Examples of typical low cost meat formulas:
- Formula A
- Beef trimmings - 60% (80% lean, 20% fat)
- Pork trimmings - 40% (80% lean, 20% fat)
- Formula B
- Beef trimmings - 50% (80% lean, 20% fat)
- Pork trimmings - 50% (80% lean, 20% fat)
Meats should be properly cured with salt and sodium nitrite (Cure #1) using the dry curing method. This will produce a pink color so typical to frankfurters or bologna. The smaller meat particle size results in a shorter curing time and emulsified meats are often cured using the faster “emulsion curing” method.
Salt, spices, binders and sodium nitrite are added directly into a bowl cutter where they are mixed with minced meat. Crushed ice or ice cold water is slowly added and as a result an emulsified paste is obtained. This emulsified mix is then stuffed into casings but can not be submitted to smoking as the curing color has not developed yet. In this particular case meats have not been cured and more time is needed in order for the sodium nitrite to react with the meat. As the meat has been very finely comminuted, it is sufficient to hang stuffed sausages overnight in a refrigerator (38º F, 3-4º C). Then they are kept for 1-2 hours at room temperature or in a warm smokehouse at around 50º C (122º F) without smoke. The reason is to dry out the sausage casings which may be moist (condensation) when removed from a cold refrigerator into a warmer room. It also provides an extra time for curing as sodium nitrite cures even faster at such high temperatures. The normal 2-3 days curing period has been eliminated. The curing method, “emulsion curing” may not be the best choice at home conditions, unless an extra refrigerator is available.
To lower costs, a commercial manufacturer tries to accomplish the entire curing process during meat cutting and emulsifying. This is possible due to the addition of sodium erythorbate or ascorbic acid, which accelerates the production of nitric oxide (NO) from sodium nitrite (Cure #1). Nitric oxide reacts with meat myoglobin rapidly producing nitrosomyoglobin (NOMb). As a result the cured red color is obtained much faster and is more stable.
Commercial producers will perform the first stages of production entirely in a bowl cutter. This saves time and space, simplifies equipment and allows the introduction of huge amounts of water.
A typical emulsifying process:
- Add beef to a bowl cutter rotating on low speed.
- Add salt, sodium nitrite (Cure#1), phosphates (if used) and ingredients and 1/3 of finely crushed ice (less wear on knives). Cut on high speed.
- Add lean pork trimmings and another 1/3 of ice.
- Add last part of ice, all spices, color enhancers (ascorbic acid, sodium erythorbate etc), fat and fat pork trimmings. Cut and mix together.
- Fat is added last as it does not absorb water and when finely chopped may smear.
- Ascorbic acid reacts sporadically when in direct contact with sodium nitrite. This is why sodium nitrite is added at the beginning and ascorbic acid last.
- About 2 - 3% salt and 0.3 - 0.5% phosphates should be added for maximum protein extraction.
- Salt soluble proteins are most effectively extracted from lean meat at 36 - 38° F (2 - 4° C).
Grind all meats with a coarse plate 3/8” (10 mm), refreeze and grind again through 3/16” (5 mm) or 1/8” (3 mm). Refreeze the mixture briefly and grind the third time through 1/8” (3 mm) plate.
Using Food Processor
A food processors is the smaller brother of a commercial bowl cutter. It allows to effectively chop meat trimmings that contain a lot of connective tissue, the task which will be hard to perform with a manual grinder. The meat should be first ground in a grinder through 1/8” (3 mm) plate and then emulsified in a food processor. The grinding process can be performed a day earlier. Most processors come with a single cutting blade, some are equipped with two knives. In both cases a lot of heat is generated and crushed ice should be added.
Fill any suitable container with water and when frozen insert warm water to remove a block of ice. Wrap a towel around it and break into smaller pieces. For preparing smaller quantities of ice the ice holding tray will suffice. The smaller ice particles the less wear and tear on the cutting knife. Adding ice flakes postpones the life of the cutting blade and keeps down the meat’s temperature. Different meats can absorb different amounts of water (see page 16) but adding 25% of crushed ice may be a good estimate. This will result in 10% sausage yield. If the sausage mass weighed 1 kg, the finished cooked sausage should weigh about 1.1 kg. Chop meat and fat gradually adding crushed ice until it is completely absorbed by the meat. If this process were performed at high temperatures the emulsion would be lost and the fat will separate from water.
A good comparison is the process of making mayonnaise or some butter sauces. For example, if oil is added too fast to egg emulsion while whisking, the emulsion will break apart and oil will come out of the solution. If butter is added to emulsion too fast or at too high temperatures, the emulsion will be lost. The remedy is to add ice and vigorously whisk again. Adding some non-fat dry milk (3%), although not necessary, will strength the emulsion and will help the finished sausage retain moisture.
Meat should be emulsified until its temperature reaches 57º F (14º C) and of course the machine must be stopped when taking measurements. Above 60º F (15º C), the fat will separate from the meat and we don’t want that. In a properly emulsified meat there should be no distinction between meat and fat particles. In commercial operations the temperature of the emulsion is continuously monitored and is kept around 15º C (59º F) or lower. If making only one type of sausage you may add all ingredients into the food processor which will eliminate the mixing process.
Making Different Sausages
- Often more than one sausage type is produced at the same time. In such a case the emulsified mixture becomes a sausage mass that becomes a base for different sausages. Of course besides salt and nitrite no other ingredients are added when making the base.
- Lean meat is manually cut into larger pieces or ground through a coarse grinder plate. The fat can be diced into 1/8” cubes. Those bigger parts will become the show meat in a finished sausage.
- Emulsified sausage base is mixed with other ingredients and stuffed into casings. Ingredients such as olives, pistachio nuts, whole peppercorns may be added as well.
- The sausage mass is stuffed into casings and cooked in water.
Mix all ingredients with a cup of cold water and pour over minced meat. Start mixing, gradually adding flaked ice or cold water until a well mixed mass is obtained. We have been making wieners and frankfurters long before food processors came to be and there is no reason why we can’t process them in the same way again.
Stuff hot dogs or frankfurters into sheep casings making 4-5” (10-12 cm) links. Hang them for 1 hour at room temperature to dry out the casings and then place the sausages in a smokehouse. The smoking step is very important during commercial manufacturing as sausages such as hot dogs or frankfurters are skinless (no casings). They are stuffed into cellulose casings and then smoked. This creates a hardened surface which becomes a sort of artificial casing. After smoking and cooking, sausages go through the machine that cuts cellulose casings lengthwise and then the casing is peeled off. The hardened surface of the sausage is strong enough to hold a sausage mass in one piece.
At home the sausages are stuffed into sheepskin casings which are edible and it is entirely up to you whether to remove the casings or not. If it comes off clean (no meat attached) and easy you may remove it. A skinless fresh sausage can be produced by stuffing meat into cellulose casings. The sausage is then frozen and the casing stripped off.
Freshly stuffed sausages are left for 1-2 hrs at room temperature or in a warm smokehouse at around 50º C (122º F) without smoke. The purpose of this step is to dry out the casings which should feel dry or tacky to the touch. We all know very well that we should not smoke wet meats or sausages. Sausages are smoked at 60-70º C (140-158º F) until a reddish-brown color is obtained. Smoking and cooking should be considered as one continuous operation.
Cooking time depends directly on the temperature when the smoking has ended. For small diameter sausages such as hotdogs or frankfurters it should not be longer than 15 minutes. Emulsified sausages are heat treated with steam or hot water. At home conditions they will be submerged in hot water at 75º C (167º F). Frankfurters are thin sausages and 15 minutes cooking time is plenty. Keep in mind that they have been smoked at 60-70º C (140-158º F) for about 60 minutes and are already warm and partly pre-cooked. If a sausage diameter is larger, let’s say Mortadella, 60 mm, you may cook it at 75 – 78º C (167 – 172º F) for 60 minutes. A very large bologna sausage may be smoked for 3-5 hours and cooked for 5 hours more. A rule of thumb dictates 10 min for each 1 cm (3/8”) of diameter of the sausage. There is no need for estimating time when a thermometer is used and cooking stops when the internal temperature of the sausage reaches 68-70º C (154-158º F).
Dip sausages in cold water to cool them down. You may have to change the water once or twice depending on the size of the container and amount of production. If possible shower them or dip them very briefly with hot water to remove any grease on the surface. Hang them and wipe off any fat with a wet cloth. The reason for cooling is to bring the temperature down outside the Danger Zone (50-30º C, 122-86º F) when most bacteria find favorable conditions to grow. Although the cooking process kills 99% of bacteria, nevertheless new bacteria which are present all around will start multiplying again on the surface of the sausage. It is in our interest to bring the temperature below 30º C (86º F) as soon as possible. The sausages can be hung between 25-30º C (77-86º F) as at those temperatures moisture and heat evaporate from the surface rapidly. Then the sausages may be placed in a refrigerator.
Spices and additives
Aromatic seeds such as cloves, ginger, allspice, cinnamon, and nutmeg are commonly added to emulsified sausages. Other popular spices are white pepper, coriander and celery seed. The following additives can be used in emulsified products: non fat dry milk, starch, soy protein isolate or concentrate, egg whites, phosphates and ascorbates.