Fermented Sausage

[delcecchi]

Here is an excerpt from a book on sausage making that I have....

 

Chapter 20 - Fermented Sausages

Introduction

Cold smoked and fermented sausages are grouped together as they are so closely related. For example fermented spreadable sausage such as Mettwurst can also be called a cold smoked sausage. Polish Cold Smoked Sausage is basically cold smoked salami or cold smoked dry sausage. All cold smoked sausages once sufficiently dried become North European versions of traditionally made Italian salami which is usually not smoked.

Traditionally, the production of fermented meats relied on bacteria present at the butcher’s premises. The facility developed its own microbiological flora in which microorganisms lived all over the establishment. Meat brought from outside had already been infected with bacteria. At some places the slaughter of the animal was performed right on the premises, which also contributed to new bacteria infecting the meat. Summing it up there was no shortage of microorganisms and this combination of bacteria from the meat and from the premises often created favorable conditions for making fermented sausages.

Plants developed different bacterial flora and sausages of different qualities were made depending on the location. In the past meat facilities were not sanitized as scrupulously as the ones of today, which helped create more favorable conditions for the bacteria to survive in the plant. These conditions were unique to each establishment and it was impossible to duplicate them somewhere else. By the same token, sausage makers were unable to produce a fermented sausage in two different locations that would have exhibited the same quality.

Some places in Italy developed a specific flora which was instrumental in producing a high quality product of a peculiar taste and flavor. Such establishments suddenly developed fame and a brand name for making wonderful meat products. They probably were not better sausage makers than their counterparts working in different locations. They were lucky to have their shop located in the area which was blessed by mother nature for making fermented sausages. They did not have much clue as to what was happening, but passed this empirical knowledge to their sons and it worked like magic.

Until the second half of the XX century, the manufacture of fermented sausages was covered with a shroud of secrecy. One of the secrets was known as back slopping, which was reusing a part of the sausage mass from the previous batch. Such inoculation helped to produce a sausage of the same quality as the one previously made. Unfortunately any defects that were acquired in following productions would be passed along, and the method is seldom used today.

Climatic differences were a significant factor in the development of different methods of smoking, drying, and preserving meat products. The best time of year was when temperatures were cooler and mildly humid. In the summer, higher temperatures and lower humidity did not favor the production of high quality sausages. The South had a drier climate with steady winds, and the best air-dried hams originated there (Spanish Serrano, Italian Parma). In the North, the weather was less predictable with cooler temperatures and higher humidity. Those conditions were ill suited for making air-dried products and smoking became the preferred method. For those reasons Mediterranean countries produced slow-fermented sausages that were only dried, and countries in Northern Europe produced fermented sausages which were smoked and dried.

Modern production is independent of outside conditions and parameters such as temperature, humidity, and air speed are computer controlled in sophisticated drying chambers. This latest technology, combined with a universal use of bacteria cultures, permit producing fermented sausages of constant quality at any time of the year. Even so, the manufacture of fermented products is still a combination of an art and technology.

The preservation of meats by fermentation has been practiced for centuries and traditional practices rely on indigenous bacteria present in meat and in the environment. These techniques are being replaced by the application of commercially grown starter cultures. Fermentation technology has become a huge part of food science and to be able to choose the right culture for a particular product, requires a basic understanding of microorganisms and their behavior.

How Fermented Sausages Differ From Others

Making a regular sausage is amazingly simple: the meat is ground, salt and spices are added, and the mass is stuffed into a casing. If this is a fresh sausage, the process ends right there and the sausage goes into the refrigerator. Then it is cooked and eaten. If making a smoked type, the sausage goes into a smokehouse and then is cooked and consumed. This is a simple and fast manufacturing process and there is no health risk present at any time if basic safety precautions are in place. On the other hand it takes a lot of effort to produce a high quality traditional fermented sausage.

This is a serious investment in time and a lot of care is needed by the sausage maker. It is almost like planting a tomato plant in the garden, a lot of pruning and watering is needed within the next three months. Or like making wine, it has to ferment, clarify, mature, and only then it is ready to be consumed. In many cases fermented sausages are not submitted to heat treatment and this separates them from other sausage types. This one missing step (lack of cooking), forces upon a sausage maker a completely new manufacturing technology in which the knowledge of microbiology plays a crucial role. Although the first steps of sausage making such as meat selection, curing, grinding, mixing and stuffing initially seem to be the same, under closer examination it becomes clear that they have to be finely tuned to new safety requirements. All tasks involved in the manufacture of fermented sausages must always be performed in such a way that meat safety is never compromised. A mistake in any of the processing steps can later spoil the sausage or bring harm to the consumer.

A recipe can be downloaded from the Internet and with some luck, one may produce quality salami at home. The problem is that the next time one attempts to make the same sausage, it will turn out completely different even if the same ingredients were used. There are a few stages of making a fermented sausage and a serious violation of established rules will spoil the product and may even make it dangerous to consume. As some sausages, notably slow fermented ones, take many weeks or even months to produce, it is a great loss to waste so much time and investment due to insufficient know-how or one’s negligence. Making fermented sausages can be considered an advanced sausage making and to produce a consistant quality sausage some understanding of meat science and microbiology must be first acquired.

It’s All About Bacteria

Making fermented sausages is a combination of the art of the sausage maker and unseen magic performed by bacteria. The friendly bacteria are working together with a sausage maker, but the dangerous ones are trying to wreak havoc. Using his knowledge the sausage maker monitors temperature and humidity, which allows him to control reactions that take place inside the sausage. This game is played for quite a while and at the end a high quality product is created.

The start of fermentation is nothing else but a war declaration by all bacteria residing inside the meat and the stuffed sausage becomes the battlefront. We have to protect the product at all costs and the two best weapons we have at our disposal are increasing meat acidity (lowering pH) and lowering its water content (Aw). We have to create conditions that will:

 

Inhibit growth of spoilage and dangerous bacteria.

Take a good care of friendly bacteria so they can prosper and work for us.

Water Activity

All microorganisms need water and the amount of water available to them is defined as water activity. Water activity (Aw) is an indication of how tightly water is “bound” inside of a product. It does not say how much water there is, but how much water is available to support the growth of bacteria, yeasts or molds.

 

Water activity of some foods

Below certain Aw levels, microbes can not grow.

USDA guidelines state:

 

“A potentially hazardous food does not include . . . a food with a water activity value of 0.85 or less.”

 

Pure water              1.00

Fresh meat & fish    0.99

Bread                       0.99

Salami                     0.87

Aged cheese           0.85

Jams & jellies           0.80

Plum pudding          0.80

Dried fruits              0.60

Biscuits                   0.30

Milk powder             0.20

Instant coffee          0.20

Bone dry                    0.00

 

Adding salt or sugar “binds” some of this free water inside of the product and lowers the amount of available water to bacteria which inhibits their growth. The most practical approach for lowering water activity is drying, although it is a slow process which must be carefully monitored, otherwise it may backfire and ruin the product. A simple scale is used to classify foods by their water activity and it starts at 0 (bone dry) and ends on 1 (pure water).

Meats were preserved throughout history and the technology was based on simple techniques of salting and drying. Both factors contribute to lowering the water activity of the meat. Freshly minced meat possesses a very high water activity level around 0.99, which is a breeding ground for bacteria. Adding salt to meat drops this value immediately to 0.96-0.98 (depending on the amount of salt), and this already creates a hurdle against the growth of bacteria. This may be hard to comprehend as we know that water does not suddenly evaporate when salt is added to meat. Well, this is where the concept of water activity becomes useful.

Although the addition of salt to meat does not force water to evaporate, it does something similar: it immobilizes free water and prevents it from reacting with anything else, including bacteria. It is like stealing food from bacteria, the salt locks up the water creating less favorable conditions for bacteria to grow and prosper. As we add more salt, more free water is immobilized, but a compromise must be reached, as adding too much salt will make the product unpalatable. It may also impede the growth of friendly bacteria, the ones which work with us to ferment the sausage. The same happens when we freeze meat though we never think of it. Frozen water takes the shape of solid ice crystals and is not free anymore. The manipulation of water content in processed meat is very important to the successful production of traditionally made slow-fermented sausages.

Removing water content by drying a sausage is a slow process which is not practical when we want to make a product safe to consume within a few days. We could dry sausages at higher temperatures by applying fast air speed, but that would only harden their surfaces, trapping the moisture inside causing the sausages to spoil. Slow, controlled drying is the method applied to traditionally made slow-fermented sausages which require three months or more to produce. As the process proceeds, water starts to evaporate making meat stronger against spoilage and pathogenic bacteria.

There eventually comes a point when there are no bacteria present and the meat is microbiologically stable. It will not spoil as long as it is kept at low temperatures and at low humidity levels. If the temperature and humidity go up, new bacteria will establish a colony on the surface and will start moving towards the inside of the sausage. The mold immediately appears on the surface.

From the graph above it can be seen that except Staphylococcus aureus, all other bacteria (spoilage and pathogenic) will not grow below 0.91. This is why drying is such an effective method of preventing bacteria growth and preserving foods in general.

Originally designed for government inspectors, the 4-inch Pawkit is a reliable water activity instrument for use on-the-go. To make a measurement flip back the sensor cover and fit the Pawkit over a standard AquaLab sample cup. A push of a button brings an accurate reading within five minutes.

 

Photo 20.1 Pawkit water activity meter. Photo courtesy: Decagon Devices Inc, Pullman, WA,USA. www.decagon.com

pH -The Measure of Food Acidity

Foods with a low pH value (high acidity) develop resistance against microbiological spoilage. Pickles, sauerkraut, eggs, pig feet, anything submerged in vinegar will have a long shelf life. Even ordinary meat jelly (head cheese) will last longer if some vinegar is added, and this type of head cheese is known as “souse.” Next time when buying meat marinade look at the list of ingredients. The list invariably includes items like vinegar, dry wine, soy sauce, lemon juice, and ingredients which are acidic or salty by nature. Although those ingredients are added mainly to tenderize meat by unwinding the protein structure, they also contribute to inhibiting the growth of bacteria. Bacteria hate acidic and salty foods and this fact plays an important role in the production and stabilization of fermented sausages.

Bacteria prefer meats with a pH of 6.0-7.0 which falls in the neutral range of the pH scale. It is in our interest to increase the meat acidity (lower pH) as this inhibits the growth of bacteria. As a result the sausage is stable and safe to consume, although it has not been submitted to heat treatment, which in many cases follows anyhow. A pH drop is accomplished by lactic acid bacteria, which consume sugar and produce lactic acid. This increases the acidity of the meat. The acidity can also be increased by directly adding additives to the meat such as Gdl (glucono-delta-lactone) and/or citric acid.

 

 

From the pH scale on the facing page, it can be seen that adding vinegar to meat will increase the acidity but adding baking soda will produce an opposite effect. Of course such ingredients have to be carefully selected as they will alter the flavor of the sausage. Using different meats and fats will produce a sausage mass of a certain pH, and the pH meat tester will provide the initial value of the pH of the mix.

The following table shows a pH value below which the listed bacteria will not grow. In the majority of today’s fermented sausages, increasing the acidity of the meat has become the main hurdle against bacteria. Almost all fermented sausages produced in the USA today are manufactured by lowering the pH of the meat. It is a profitable and risk free method for commercial producers, although the taste and flavor of the product leaves much to be desired.

Name                  Min pH

Salmonella              3.8

hsolist. botulinum           5.0

Staph. aureus         4.2

Campylobacter        4.9

Listeria                    4.4

E. coli                      4.4

Shigella                  4.0

Bacillus                  4.3

 

Controlling pH and Aw is crucial when making fermented products, for the purpose of this book it is enough to know that bacteria hate high acidity (low pH) and low water levels (Aw).

 

 

Making Fermented Sausages

 

Meat selection. Only the best raw materials are chosen for making dry or semi-dry sausages. Any blood clots and glands must be removed as these may accumulate undesired bacteria. Those bacteria will then multiply during the curing or fermentation step and will affect the quality of the product. Meats must be well trimmed of gristle and sinews. Such defects are not apparent in emulsified sausages but will strike out in coarsely ground fermented sausages. The fact that fat has a lower acidity is not of grave concern as it accounts for the minor parts of a sausage and the initial pH of the sausage mass is the average of all meats.

We are not going to go into details on selecting meats the way commercial meat plants do. Using terms like PSE meat, or DFD, or MDM is of little concern for a home sausage maker, and if he wants to expand his knowledge in this area he can address any of the widely available books on meat science. Buying ground meat is not a good solution as it has the shortest life due to its large surface area and it has a large bacteria count. Typical pH values of raw meats follow below:

Raw material

pH

Pork

5.7 - 5.9

Back fat

6.2 - 7.0

Emulsified pork skins

7.2 - 7.8

Beef

5.5 - 5.8

Chicken breast

5.6 - 5.8

Chicken thigh

6.1 - 6.4

Different meats are used to make fermented sausages: pork, beef, lamb, goat, venison, poultry or a combination thereof. In Germany fermented sausages are often made from equal amounts of pork and beef, in Poland pork is more popular. Hungarian and Italian sausages contain mostly pork. Naturally fermented and dried meats have been made for centuries all over the world and although the recipes may vary, the basic technology remains the same.

Chicken. Trying to make a sausage from chicken meat only presents some problems: high pH, high Aw and that means favorable conditions for bacteria growth. Campylobacter jejuni is a typical pathogen found in poultry meat.

Fish. Fermented fish products are popular in countries such as the Philippines, Japan, and China. The products are not so much as fermented sausages but fermented fish paste and fish sauce which are used for general cooking. Rice is used as a filler and the source of carbohydrates for fermentation. Two known products are Balao Balao (fermented rice and shrimp) and Burong Isda (fermented rice and fish). There was research done on making fermented fish sausages and the customer acceptance in order of preference follows below:

 

Fish-pork, the highest score.

Fish-beef.

Fish-chicken.

Non-fish beef-pork sausage was rated the highest of all. Using starter cultures and good manufacturing processes a semi-dry fish sausage can successfully be made at home.

Venison. Sausages made of venison are commercially made for sale in Canada and Alaska. Venison is lean meat and it should be mixed with pork back fat, fatty pork, or a combination of pork and beef. A proportion of 60% venison to 40% other meats is a good choice. Wild game meat (except venison) is at risk of being infected with trichinosis and the regular freezing methods as applied to pork may not be enough. Freezing may not kill larval cysts in bears and other wild game animals that live in Northwestern U.S. and Alaska. That meat has to be cooked to 160º F (71º C) internal temperature, but this step cannot be applied to fermented sausages which are not cooked. Curing meat with salt for prescribed times will prevent trichinosis as well (see Appendix A).

Fat

When making fermented sausages use pork back fat. It is hard, it has a higher melting point, and it will make a great sausage. Soft fat (belly) smears easily and may adhere to the inner casing surface, clogging up the pores and affecting drying. It may also coat meat particles which will affect the drying process. Although soft fat is a poor choice for making sliceable sausages, it can be successfully used for making fermented spreadable sausages (Mettwurst, Teewurst), especially the ones with a fine grind. Make sure the fat is partially frozen before it is ground or cut. Fat contains little water (10-15%), so if the sausage is fatty it contains less water. As a result the drying step is shortened.

Beef fat has a higher melting temperature than pork but is yellowish in color which affects the appearance of the product where discrete particles of fat should be visible. In addition beef fat does not taste as good as pork fat which makes it a secondary choice. There are some that may object to pork fat on religious grounds and beef fat (tallow) will have to do. In large metropolitan areas it may be difficult to obtain back fat. It may be easier to obtain back fat from ethnic butcher stores (Polish, German, Spanish, Thai) but it is often heavily salted. Some supermarkets carry heavily salted pork fat and it will have to be desalted in cold water (48 hours) before grinding. A few water changes are necessary.

Chicken fat. Fermented sausages can be made of chicken but a big problem is chicken fat. It is too soft and melts at such low temperatures that it is of no practical use. Chicken fat contains more water and less collagen structure than other fats which makes it soft and semi-liquid at room temperature due to its low melting point. When submitted to heat treatment, chicken fat will melt inside the sausage creating oily pockets and make the sausage seem like a fat product. For those reasons pork fat should be added to a sausage but it can not be classified as an all chicken sausage anymore. Using starter cultures and good manufacturing processes, a semi-dry chicken sausage can successfully be made at home.

Smoking

Smoking may or may not be utilized in the production of fermented sausages. It has been used in countries in Northern Europe where due to colder climate and shorter seasons, the drying conditions were less favorable than in Spain or Italy. Smoking imparts a different flavor, fights bacteria, (especially on the surface of the product) and thus prevents the growth of molds on fermented sausages.

Mold is desired on some traditionally made Italian salamis and obviously smoking is not deployed. It should be pointed out, that when making slow-fermented sausages only cold smoke should be applied and its temperature should correspond to the fermentation or drying temperature present at a particular time. Applying smoke which is much cooler than the fermentation temperature will slow down fermentation.

Applying smoke which is much hotter than the fermentation or drying temperature will create favorable conditions for the growth of undesirable bacteria. When making traditional slow-fermented sausages we apply fermentation temperatures around 66° F, 18° C and even less when drying. To match these values we have to apply cold smoke that falls more or less in the same temperature range < 72° F, 22° C. It is a known fact that smoke possesses antibacterial properties and smoking meats was one of the earliest preservation methods. Prolonged cold smoking is the most effective of all smoking methods as it thoroughly penetrates meat.

Smoke which is applied early in the fermentation stage will definitely inhibit the growth of lactic acid bacteria to some degree, especially if the diameter of the sausage is small. In such a case it will be wiser to wait until fermentation is over before the smoke is applied. Applying smoke during the fermentation period creates a barrier to the growth of Staph.aureus at the surface of the product where toxin production may be a problem.

Cold Smoke And Fermented Sausages

When smoking fermented products such as dry salami or German spreadable sausages it is of utmost importance to keep smoke temperature down. German meat technology books recommend applying cold smoke below 64° F , 18° C for about 3-4 days. Slow fermented dry sausages and fermented spreadable sausages can be cold smoked only. The reason being that these sausages are never cooked and applying smoke at higher temperatures will create favorable conditions for the growth of undesirable bacteria. The product will spoil and might become dangerous to consume.

Spreadable sausages are neither dried nor cooked and after cold smoking must be kept in a refrigerator. The initial drying temperature for fermented sausages falls into 64 → 59º F, (18 → 15º C) range and cold smoke (< 72º F, 22º C) fits nicely into this range. Then drying continues at temperatures below 59º F, 15º C. To sum it up the length of cold smoking is loosely defined, but the upper temperature should remain below 72º F, 22º C.

Unfortunately, this rule puts some restraints on making slow-fermented sausages in hot climates for most of the year, when using an outside smokehouse. You can’t produce cooler smoke than the ambient temperature around the smokehouse, unless some cooling methods are devised.

The quote from “The Art of Making Fermented Sausages” follows below:

“Think of cold smoke as a part of the drying/fermentation cycle and not as the flavoring step. If the temperature of the smoke is close to the fermentation temperature, there is very little difference between the two. The sausage will still ferment and the drying will continue and the extra benefit is the prevention of mold that would normally accumulate on the surface. Cold smoking is performed with a dry, thin smoke. If we applied heavy smoke for a long time, that would definitely inhibit the growth of color and flavor forming bacteria which are so important for the development of flavor in slow-fermented sausages (salamis). As drying continues for a long time and cold smoking is a part of it, it makes little difference whether cold smoke is interrupted and then re-applied again.”

Semi-dry sausages, which are of fast-fermented type, are fermented at higher temperatures. These sausages can be smoked with warmer smoke as they are subsequently cooked.

Fermentation and Conditioning. In commercial plants the process of grinding, mixing and stuffing is undertaken at a low temperature (32º F, 0º C) and as the cold sausage is placed in a warmer fermenting room, the condensation will appear on the surface of the sausage. To prevent this the sausage must remain in the fermentation chamber at a prevailing temperature for 1-6 hours (depending on its diameter) at low humidity (60%, no air speed) until the moisture evaporates. If air draft is applied at such low humidity, excessive drying will develop and case hardening will occur. This would affect subsequent fermentation and the drying processes.

In simple terms meat fermentation is spoilage of meat by bacteria. If this process is left to itself, the meat will spoil, but if it is properly controlled, the result is a fermented product. Meat fermentation is accomplished by lactic bacteria, either naturally present in meat or added as starter cultures. These bacteria feed on carbohydrates (sugars) and produce lactic acid and small amounts of other components.

Fermentation is required not only to produce a highly desirable product, but also to prevent the growth of spoilage and pathogenic bacteria. When a sausage is introduced into a fermentation chamber, the bacteria hold all cards in their favor:

 

Warm temperature - right inside of the Danger Zone.

Moisture - meat contains 75% water.

Sugar (food) - little sugar is present in the meat itself (glycogen) but extra amounts are usually added.

Oxygen, present in air. Food spoilage bacteria require oxygen to grow, but there are bacteria that thrive without oxygen.

When a sausage is stuffed the only barrier that protects the meat from spoiling is salt and nitrite which were introduced during curing or mixing. The selected meat always contains some bacteria and they will grow in time. It is of the utmost importance to process meats with a bacteria count that is as low as possible. Commercial producers add chemicals such as Gdl (glucono-delta-lactone) or citric acid into a sausage mass to rapidly increase the acidity of the meat and to create an extra margin of safety. Unfortunately, this introduces a sourly flavor to the sausage typical of fast fermented salamis. There is a fierce competition among different groups of bacteria for food. Bacteria that are beneficial to us slowly but steadily gain the upper hand in this fight by eliminating the food spoilage and pathogenic types. “Survival of the fittest” at its best. The reason that beneficial bacteria get the upper hand in this war is that they are:

 

Stronger competitors. This becomes much more pronounced when starter culture is added which brings millions of beneficial bacteria into the mix.

Better tolerate exposure to salt, nitrite and decreased water levels. Salt is always added to meat and depending on the amount added, it binds some free water which would normally be available to bacteria. As a result the Aw water activity level of a sausage mix drops from 0.99 (fresh meat) to 0.96-0.97.

Although the addition of salt, nitrite and starter cultures to a sausage mix creates favorable fermentation conditions, nevertheless undesired and dangerous pathogenic bacteria such as Listeria monocytogenes, Salmonella, Staphylococcus aureus and E. coli 0:157:H7 are still able to grow, albeit at a much slower pace.

When a sausage is placed in a warm fermentation chamber, all bacteria types spring into action and start to multiply, but they react to the new environment differently:

 

Spoilage bacteria (Pseudomonas) which are aerobic (need oxygen), start to choke as there is little air inside of the sausage. The salt and lowered moisture further inhibits their growth. Once lactic acid bacteria start to produce lactic acid, the increased acidity inhibits spoilage bacteria even more.

Lactic acid bacteria (Lactobacillus and Pediococcus) are quite resistant to salt and function well at slightly reduced water levels. After a short lag phase they start to metabolize sugar and produce lactic acid which starts to create a barrier against undesirable types. As they grow in numbers, they eat more sugar and multiply again.

Color fixing and flavor producing bacteria (Staphylococcus and Kocuria) tolerate increased salt levels very well, but they grow slowly. They can grow in the presence of oxygen or without it. They don’t like increased acidity and at pH below 5.5 they become less effective. In fast-fermented sausages a drop of pH 5.0 can be achieved in just 12 hours giving them no chance to perform. They need not days, but months of time to break meat proteins and fats in order to produce all those aroma releasing enzymes.

Pathogenic bacteria are kept in check primarily by salt and nitrite. Once lactic acid bacteria start making lactic acid, this increasing acidity starts to inhibit pathogenic bacteria, especially Staphylococcus aureus,which is very sensitive to acidity though it can function very well at low moisture levels .

In addition, some lactic acid bacteria strains (Pediococcus acidilactici, Lactobacillus curvatus) can produce bacteriocins that are very hostile towards wild and unwanted lactic bacteria strains and pathogenic Listeria monocytogenes.

The main product of fermentation is lactic acid and the main cause is an increased acidity of meat (lower pH). The more sugar that is metabolized by the lactic acid bacteria, the more lactic acid is produced and the higher acidity of meat is obtained. This increased acidity of meat known as pH drop, erects the barrier against the growth of spoilage and dangerous bacteria.

The speed of fermentation is due to the temperature and higher temperatures produce faster fermentation. If the fermentation temperature drops to <12º C (53º F), the lactic acid bacteria may stop metabolizing sugar. How acidic the sausage becomes depends on the amount and type of sugar introduced. If more sugar is added, a higher acidity (lower pH) is obtained and the sausage gains a more sourly flavor.

In traditionally made dry products the proper fermentation can take place only if there is a sufficient number of lactic bacteria in the meat to begin with. To increase their number a long curing step was performed. Unfortunately, spoilage and pathogenic bacteria were growing as well, although at a much slower rate due to the preventive effects of salt and Nitrate. In the latest production methods, huge numbers of lactic acid bacteria (starter cultures) are introduced into the meat right at the beginning of the process and that guarantees healthy and strong fermentation. These armies of beneficial bacteria start competing for food with other undesirable bacteria types, decreasing their chances for growth and survival. Fermentation stops when no more lactic acid is produced by bacteria. This happens when:

 

No more sugar is available to lactic acid bacteria.

There is not enough free water (Aw < 0.95) available to lactic acid bacteria. This can happen when a sausage dries too fast during fermentation due to low humidity and fast air speed.

Temperature is lowered ( 53º F, < 12º C) or product is heated (> 120º F, 50º C).

Fermentation is performed by Lactobacillus or Pediococcus lactic acid bacteria. Lactobacillus and Pediococcus require different temperatures for growth and this is what basically separates them. Depending on the type of a sausage desired (slow, medium or fast-fermented), different amounts and types of sugars will be chosen and in each case fermentation will run differently. In the past, it was all very simple as traditional sausages were manufactured with very little (sometimes none) sugar. Nitrate was always added, and we were not even aware of the fact that there was something called “nitrite” that cured meat. Today, the commonly available starter cultures help us to produce fermented sausages of many types such as slow or fast fermented, dry or semi-dry, sliceable or spreadable, with mold or without, etc.

Choosing a type of sausage to make, decides the fermentation type and parameters of the fermentation chamber.Based on that choice, the proper type and amount of sugar will be added into the mix. The process of meat fermentation in slow or fast-fermented products varies slightly depending on the sausage type that is produced. The processing steps prior to the fermentation stage such as meat selection, curing, grinding, mixing and stuffing remain the same in both cases. The only difference is that different amounts of sugar and different cultures are used. Nowadays, starter cultures are added regardless of what sausage type is produced.

The temperature of the sausages should increase to the recommended fermentation temperature of a particular culture as fast as possible, to create the best starting conditions for the growth of starter culture bacteria. If the temperature is increasing slowly, the bacteria that is naturally present in meat will have favorable conditions to grow before culture bacteria start competing with them.

Fermentation starts at a high humidity (> 90%) to slow down the moisture removal from the sausage. Adding 3% salt will drop Aw water activity to 0.96-0.97 (salt immobilizes some of the free water) and drying too quickly may drop Aw to < 0.95 which will have a detrimental effect on the growth of lactic acid bacteria and fermentation will be inhibited. All bacteria types need free water to survive and lactic acid bacteria are not an exception. If humidity is high, but air speed is restricted, too little drying will take place which is indicated by slime that forms on the sausage. Once the fermentation has taken place the drying can be more aggressive.

As to when fermentation stops and drying begins, there is no easy answer especially in the case of slow-fermented products that are made with little sugar, which leads to a slow and small pH drop. pH will have to be periodically monitored and once it is at its lowest, it means that there is no more lactic acid production and no more fermentation.The sausage pH, not the time, is the factor that determines when the fermentation is completed. It should be noted that when yeasts and molds appear on the sausage during the drying process, ”reversed” fermentation will take place as these microorganisms consume some of the lactic acid that was produced during fermentation. This will lower acidity (increase pH) further contributing to a milder flavor in the slow drying sausages. There are processors of dry products that limit the entire process to one long drying step.

The stuffed sausage is introduced into the drying chamber at 6-15º C, 42-58º F, where it remains for the rest of the process.

In general, faster fermentation results in a lower pH even if the same amount of sugar is added. According to Chr. Hansen a 5º C increase in temperature, if close to the optimum growth temperature for the specific lactic acid bacteria, doubles the rate of lactic acid formation.

The factors affecting fermentation:

 

Temperature.

Type of sausage (fast, medium or slow-fermented), the time can be from 12 hours to 8 days.

The method of production (chance, back slopping or starter cultures).

Sugar type.

pH lowering ingredients (Gdl, citric acid).

Salt concentration.

Meats used, pork ferments faster than beef (lower starting pH).

Drying

When the sausage is stuffed its Aw should not be lower than Aw 0.96 as bacteria need some moisture to grow. Color and flavor forming bacteria (Staphylococcus, Kocuria) are aerobic (need oxygen to survive) and are concentrated close to the surface of the sausage (area with most oxygen). They are sensitive to changing water activity levels and fast drying at low humidity levels will rapidly remove moisture from the surface area of the sausage. This will inhibit the action of color and flavor forming bacteria and will affect the development of proper color and flavor. A gray surface ring is a typical example. Lactic acid bacteria are less sensitive to water activity and perform well until water activity drops down to 0.92.

Drying is normally performed at 66 → 54º F, 18 → 12º C with decreasing humidity, from about 85% to 65-70%. Higher temperatures and humidity over 75% will promote the development of mold on the surface of the sausage. When making slow fermented sausages without starter cultures, drying temperatures should fall in 54-59º F, 12-15º C range as Staph.aureus starts growing faster at 15.6º C (60º F) and obviously it is best to avoid this and higher temperatures.

Sausages dry from inside out and and to have a correct drying process, there must be a balance between moisture diffusion towards the surface and moisture evaporation from the surface. If diffusion is faster than evaporation, moisture will accumulate on the surface of the sausage, causing it to be slimy and yeasts and molds will follow. If evaporation is faster than diffusion, the outside surface area of the sausage will dry out and harden creating a barrier to subsequent moisture removal. As a result moisture will be trapped inside of the sausage, creating favorable conditions for the growth of spoilage and pathogenic bacteria.

Water activity can be lowered faster in a sausage which contains more fat than a leaner sausage. Meat contains about 75% of water but the water content of fat is only about 10 - 15%. A fatter sausage containing less meat also contains less water and will dry out faster.

Drying basically starts already in the fermentation stage and the humidity is kept at a high level of about 90-95%. Air flow is quite fast (0.8 m/sec) to permit fast moisture removal but the high humidity level moisturizes the surface of the casing preventing it from hardening. Drying is a very important process especially in the initial stages of production. One may say why not to dry a sausage very quickly which will remove moisture and be done with all this pH stuff and bacteria.

Well, there are basically two reasons:

1. The outside layer of the sausage must not be hardened as it may prevent the removal of the remaining moisture. It may affect the curing of the outside layer which will develop a gray ring that will be visible when slicing the sausage.

2. Bacteria naturally found in meat and/or introduced starter cultures need moisture to grow. They have to go through the so called ”lag phase” first. Only then, can they metabolize sugar and produce lactic acid. Once, when a sufficient pH drop is obtained, lactic acid bacteria are not needed anymore and more moisture can be removed.

Drying is affected by the following factors:

 

Humidity - higher humidity, slower drying.

Temperature - higher temperature, faster drying.

For the perfect drying the humidity of the drying room should be 5% lower than the water activity (Aw) within the sausage. This requires water activity measurements and computer operated drying chambers where parameters such as temperature, humidity and air speed are continuously monitored and readjusted. This relationship remains constant and every time the water level drops, the humidity is lowered accordingly. At home we have to improvise, and do our best under circumstances which are present during production. And it can be done as the best proof lies in the fact, that we have been making those products without sophisticated equipment in the past. Increasing the acidity of the meat (lower pH) facilitates drying and the movement of moisture towards the surface is much smoother. As the pH drops, it approaches the isoelectric point of the myofibrillar proteins (actin and myosin) where their ability to bind water reaches a minimum. This happens around pH of 4.8-5.3. In simple words, lowering pH aids in the removal of moisture. Depending on the method of manufacture, diameter of a casing and the content of fat in a sausage mass, fermented sausages lose from 5 - 40% of their original weight.

Drying continues after the fermentation stage and more moisture is removed from the sausage. This becomes easier as the acidity increases as the forces binding water inside, lose some ot their holding power. As the Aw (water activity) keeps dropping lower, the humidity level is decreased to about 0.85-90%. Maintaining previous fast air flow may harden the surface of the casing so the air speed is decreased to about 0.5 m/sec (1.8 miles/per hour-slow walk). And the process continues until the desired amount of dryness is obtained. There is less available water to bacteria and the sausage becomes more stable.

 

The length of the sausage has no influence on drying time.

Sausages should be dried at a rate not higher than the moisture losing ability of the sausage.

Traditionally made sausages have pH of about 5.3 and Aw about 0.88 at the end of the drying process.

The drying chamber should not be overloaded as a uniform air draft is needed for proper drying and mold prevention.

Air speed - higher air speed, faster drying.

Casing type (pore size) - bigger pores, faster drying.

Amount of fat - more fat in sausage, faster drying.

Meat particle size - bigger size, faster drying.

Sausage diameter - bigger diameter, slower drying.

Sausage length does not affect drying.

A medium diameter sausage should lose about 0.5-0.7% of its weight per day when in a drying chamber.

Load capacity of the drying room-fully loaded chamber will dry slower as air movement is restricted.

Molds will develop more quickly if there is no air draft at all. Excessive drying hardens the surface and closes the casing pores.

If the outside of the sausage becomes greasy, it should be wiped off with a warm cloth otherwise it may inhibit drying.

Starter Cultures

Although lactic acid bacteria are naturally present in meat, their quantity and qualities are hard to predict. In most cases they are of a hetero-fermentative type and that means that they not only produce lactic acid by metabolizing carbohydrates, but also create many different reactions which can produce unpleasant odors and affect the entire process. Starter cultures are of a homo-fermentative type and will produce lactic acid only.

The addition of up to 10 millions of bacterial cells per gram in a lactic acid culture assures microbial dominance over other undesirable microorganisms that might be present. Those other microorganisms might be unwelcome lactic acid bacteria that were naturally present in meat or pathogenic bacteria that must be eliminated. Although commercially grown starter cultures have been around since 1957, it is only recently that sausage equipment and supplies companies carry them in catalogs.

Storing

Fermented sausages (except spreadable sausages) can be stored at 10-15º C (50-59º F), 75% humidity. If humidity is lower, the sausage will lose more moisture and weight which will amount to a lower profit. Higher humidity will invite molds to grow on the surface. Spreadable sausages which are neither dried nor cooked, must be refrigerated.

In time, there will be some flavor deterioration in dry fermented meats due to fat oxidation, also known as rancidity.Oxidation is usually started by the action of a catalyst, which includes heat, light, or oxygen. Rancidity can develop in fermented products rapidly if fermentation proceeds very slowly, which can be an issue in slow fermented products that are made without starter cultures and with little sugar. Sodium nitrite is a powerful antioxidant and nitrite cured meats have a longer shelf-life. Applying smoke also retards the onset of rancidity. Rancidity is a quality issue, not a safety issue.

Culture Types

Cultures can be classified into the following groups:

 

Lactic acid producing cultures (fermentation).

Color fixing and flavor forming cultures (color and flavor).

Surface coverage cultures (yeasts and molds).

Bio-protective cultures (producing bacteriocins). You may think of bacteriocins as some kind of antibiotics which kill unwanted bacteria. Some of the lactic acid cultures, for example, (Pediococcus) possess antimicrobial properties which are very effective in inhibiting not only Staph.aureus, but also Salmonella, hsolist.botulinum and other microorganisms including yeasts.

The advantages of starter cultures are numerous:

 

They are of known number and quality. This eliminates a lot of guessing as to whether there is enough bacteria inside the meat to start fermentation, or whether a strong curing color will be obtained.

Cultures are optimized for different temperature ranges that allow production of slow, medium or fast-fermented products. Traditionally produced sausages needed three (or more) months to make, starter cultures make this possible within weeks.

Production of fermented sausages does not depend on ”secrets” and a product of constant quality can be produced year round in any climatic zone, as long as proper natural conditions or fermenting/drying chambers are available.

They provide safety by competing for food with undesirable bacteria thus inhibiting their growth.

There are many manufacturers of starter cultures that are used in Europe and in the USA, for example cultures made by the Danish manufacturer “Chr. Hansen”. Their products demonstrate superior quality and are easily obtained from American distributors of sausage making equipment and supplies. Some of the popular cultures are listed below:

Bactoferm™ T-SPX - slow-fermented culture for traditional fermentation profiles applying fermentation temperatures not higher than 24º C (75º F). 25 g of culture ferments 200 kg of meat.

Bactoferm™ F-LC - bio-protective culture capable of acidification as well as preventing growth of Listeria monocytogenes. Controlling Listeria monocytogenes is not easy as it is so widespread. It can be found in livestock, in humans, on processing equipment and in other locations of meat processing plants. To prevent its growth, proper sanitation and proper temperature control is needed in all steps of the manufacturing process. The culture works in a wide temperature range. Low fermentation temperature (< 77ºF, 25º C) results in a traditional acidification profile whereas high fermentation temperature (95-115º F, 35-45º C, ) gives a US style product. 25 g of culture ferments 100 kg of meat. Use dextrose as this culture ferments sugar slowly.

F-RM-52 - Fast culture targeted for fermentation temperatures 70-90º F, 22-32º C.

LHP - Extra fast cultures targeted for fermentation temperatures 80-100º F, 26-38º C. Both cultures, F-LC and LHPare similar and either one can be applied.

M-EK-4 - White mold cultures for surface treatment.

There is not one universal temperature for fermenting, drying or even storing. There is an acceptable range of temperatures that correspond to each particular process. When starter cultures are used, the fermentation temperature can vary from the minimum to the maximum setting recommended by the manufacturer and as long as we follow this advice the sausage will turn out fine. Technical information sheets provide the recommended temperatures for fermentation, however, bacteria will also ferment at lower temperatures, just more slowly. For example, the technical information sheet for T-SPX lists temperatures as 26-38º C, optimum being 32º C. T-SPX will ferment as well at 20-24º C which is not uncommon for ”European” style sausages and 48 hours or more is not atypical.

When freeze-dried cultures are used it is recommended to disperse them in water. Adding 25 grams of powdered culture to 200 kg (440 lbs.) of meat makes uniform distribution quite challenging. That comes to about ½ teaspoon to 4.5 kg (10 lbs.) of meat and the culture must be very uniformly dispersed otherwise defects will occur later on. For those reasons it is advisable, especially at home conditions, to mix ½ tsp of culture in ½ cup (150 ml) of distilled water and then pour it down all over the meat. Any tap water which is chlorine free will do, the problem is that different cities, or countries, sanitize water in different ways. Chlorine will kill bacteria and the process will suffer. For this reason it is recommended to use distilled water. Mixing freeze-dried cultures with cold water for 15-30 minutes before use allows them to “wake up” and to react with meat and sugar faster when introduced during the mixing process. Cultures distributed by Internet online companies are of the freeze dried type.

Most people mix all ingredients together, sometimes with little water in a blender as this allows better distribution of ingredients during mixing. Starter cultures should not be mixed with salt, nitrite or spices in advance as unpredictable growth of culture bacteria may occur (all they need is a bit of moisture from spices). As a result starter cultures with different characteristics will be introduced into the sausage. Starter cultures should be added to the sausage mass just before stuffing. They may be mixed with other ingredients at the same time, but the stuffed sausage should enter the fermentation stage as soon as the sausages reach room temperature. Once fast-fermented starter culture or Gdl has been added to the sausage mix, the mix should be immediately filled into casings.

Safety Hurdles

Think of safety hurdles as a sophisticated alarm system. It consists of many components: perimeter protection (switches on doors, foil on windows, switch mats, trap wire etc), then a second line of defense comes into play: (motion detectors, glass breakage detectors, photo-electric eyes etc). Fermented sausages are like a sophisticated alarm - they need many security measures (hurdles) to stop intruders (undesirable bacteria). Using a combination of different hurdles is more effective that relying on one method only.

For example the first hurdle is an application of salt and sodium nitrite which slows down spoilage and keeps pathogenic bacteria at bay. This first hurdle is a temporary one, and if we don’t follow up with additional hurdles, such as lowering pH and then lowering water activity Aw, the product will spoil.

Typical safety hurdles:

 

Processing meats with a low bacteria count at low temperatures.

Curing with salt and nitrite/Nitrate.

Lowering pH of the meat to < 5.3.

Lowering Aw (water activity) by drying to < 0.91.

Using bio-protective cultures.

Smoking.

Cooking.

Spices.

Cleanliness and common sense.

Bacteriological Benefits of Smoke

Smoking provides some antimicrobial (phenols and acids) and antioxidant (phenols) properties to the product but must be considered an additional safety hurdle and not the main one. Yes, it provides more microbiological protection in cold smoked products which are saturated with smoke in all areas, but we can not relay on this method alone.Drying is what makes cold smoked products safe. Some dry salamis are smoked and others, notably Italian, are only dried without any smoking. In hot smoked products cooking provides safety and smoking is just a flavoring step.Any bacteriological effects of smoke will be limited to the surface area only and not the inside. Dipping a sausage into a solution of salt and vinegar will provide extra safety to the outside of the sausage as well.

Nitrates

You must not make fermented sausages without nitrite/Nitrate as they provide protection against pathogenic bacteria. For your own safety nitrates should be applied at the maximum allowable limits. Research that was done on the flavor of traditionally produced sausages concluded that sausages made with Nitrate exhibited superior quality to those that were made with nitrite only. A panel of professional testers-judges has made this finding (A. Marco, J.L. Navarro. M. Flores, The Sensory Quality of Dry Fermented Sausages as Affected by Fermentation Stage and Curing Agents, Eur Food Res Technol, (2008), 226:449-458.).

In the past, Nitrate was predominantly used as a curing agent as most sausages were of the dry type. Those sausages were made slowly and at low temperatures, which provided sufficient time for color and flavor forming bacteria to reduce Nitrate to nitrite. With today’s faster production times nitrite (Cure #1) is used as it does not depend on microbial action and works better than Nitrate at low temperatures. Employing only Nitrate during low temperature curing does little for the color as curing bacteria work best at 8º C (46º F) or higher. For these reasons a combination of nitrite and Nitrate (Cure #2) is applied to slow-fermented products, as nitrite starts reacting with meat at low temperatures and Nitrate guarantees a stable color during long term drying. Fast or medium-fast fermented sausages are made with nitrite (Cure # 1) only.

Salt

When making fermented sausages use between 2.5-3.5 % salt as this combined with nitrite, is your first line of defense against undesirable bacteria. Almost all regular sausage recipes (fresh, smoked, cooked etc) contain 1.5-2% of salt which is added to obtain a good flavor. These amounts are not high enough to provide safety against bacteria and there is no room for compromise. When adding salt to fermented sausages try to think of salt as a barrier against undesirable bacteria. Use 3.0 - 3.5% salt when making traditionally fermented dry sausages without starter cultures. For all other types use 2.5%, common non-iodized salt. Canning rock salt is available at all supermarkets and it is pure without anti-caking ingredients.

Although starter cultures assure proper fermentation, nevertheless to inhibit undesirable bacteria in the beginning of the process, the salt level should remain high (2.5-3%).

Sugar

Fresh meat contains very little glucose (0.08-0.1%), which is not enough for lactic acid bacteria to produce any significant amount of lactic acid. Adding sufficient amounts of sugar is of great importance for fast-fermented sausages which rely on acidity as a main safety hurdle. About 0.3-1% dextrose (glucose) must be introduced into meat when making a fast fermented product.

For slow-fermented sausages the amount of added sugar is much smaller (0.1 - 0.3%), as the microbiological safety is achieved by drying products and not by increasing acidity. Many traditional long dried sausages do not employ any sugars at all.

In general, increasing sugar levels up to 1% decreases pH proportionally. In specific products (e.g. American pepperoni), limiting sugar to 0.5-0.75% creates adequate fermentation with no residual carbohydrate present after fermentation. A lower pH is obtained with increasing temperature at the same sugar level.

Amount of sugar in %

Final pH

0.3

more than 5.0

0.5 - 0.7

less than 5.0

1.0

4.5

Carbohydrate (1%)

Lactic acid produced (%)

Final pH

Glucose

0.98

4.08

Saccharose

0.88

4.04

Maltose

0.72

4.24

Maltodextrin

0.54

4.54

Galactose

0.31

4.83

Raffinose

0.08

6.10

Lactic acid production and final pH achieved by Lactobacillus pentosus during growth in MRS-broth at 86º F, 30º C for 12 hours. Data of Chr. Hansen

The types of sugar which may be used in making fermented sausages are listed below:

 

Glucose - also known as dextrose, is sugar refined from corn starch which is approximately 70% as sweet as sucrose. It is the simplest form of sugar that serves as a building block for most carbohydrates and because of its simplicity it can be directly fermented into lactic acid by all lactic bacteria. It is the fastest acting sugar for lowering pH. As lowering pH is the main hurdle against bacteria growth in fast-fermented sausages, dextrose is the sugar of choice.

Sucrose - common sugar (also called saccharose) made from sugar cane and sugar beets but also appears in fruit, honey, sugar maple and in many other sources. Sucrose is composed of 50% glucose and 50% fructose and is the second fastest acting sugar. It can be used with Gdl in medium-fermented sausages. In slow-fermented sausages common sugar can be used as it has been used for hundreds of years. Addition of glucose and common sugar contributes to the safety of the sausage, strong curing color and better flavor.

Fructose - commonly found in fruits and honey. It can be obtained in a supermarket.

Maltose - malt sugar is made from germinating cereals such as barley which is an important part of the brewing process. It’s added mainly to offset a sour flavor and to lower water activity as its fermenting qualities are poor.

Lactose - also referred to as milk sugar, makes up around 2–8% of milk (by weight) and has poor fermenting qualities. It is composed of glucose and galactose. Non fat dry milk contains about 52% of lactose. Lactose binds water well. Non fat dry milk can be obtained in a supermarket.

Galactose - makes up half of lactose, the sugar found in milk.

Raffinose - can be found in beans, cabbage, broccoli, asparagus, other vegetables and whole grains.

Maltodextrin - type of sugar usually made from rice, corn, or potato starch. It is commonly used for the production of natural sodas.

Spices. Without a doubt black pepper is the most popular spice added to fermented sausages (0.2-0.3%, 2-3 g/kg). The most popular spices in the manufacture of fermented sausages are pepper and garlic. Spices added to the sausage also contribute to the flavor, more so in the case of fast-fermented products. Spices lose their aroma rapidly and their contribution to flavor in slow-fermented sausages is weaker.

Flavor

Dry sausages made with pepper only will have the wonderful mellow cheesy flavor, which is created in time by the reaction of bacteria with meat. Fast-fermented sausages will always exhibit this tangy and sourly flavor as flavor forming bacteria don’t get sufficient time to work with meat. In this case a variety of spices, sugars and syrups can somewhat off set the acidity of the meat.

The metabolism of sugar by bacteria and lactic acid production is directly responsible for the tangy or sour taste in fast fermented sausages. The lower pH the more sourly flavor especially noticeable in fast-fermented products. The true salami flavor of a slow-fermented sausage depends mainly on the breakdown of sugars, fats and proteins through the fermentation and drying process. These reactions are products of microbiological action of color and flavor forming bacteria, which need sufficient time in order to develop a true salami flavor.

The little fermentation that takes place in dry products, is due to lactic acid bacteria reacting with small amounts of sugar (glycogen) present in meat. Even today, in true Hungarian salami, the addition of starter cultures and sugars is not permitted in order to eliminate any possibility of the acidic taste of the sausage. The commercial salami flavor is influenced by the acidity of the sausage and addition of spices and flavorings. This is a poor imitation of the traditional sausage and although products may be called salamis or pepperonis they have little in common with the original.

As the sausage matures, its flavor becomes more mellow due to a slight decrease in acidity. This also happens to wines and brandy, as they mature the taste improves and brandy in time becomes cognac. The noticeable difference in flavor between South European, North European and American femented sausages is not due to spice combinations, but to different manufacturing methods which are used for making sausages. These methods influence the choice of starter cultures, fermentation temperatures, amounts and types of sugars, and the resulting pH drop. Another huge factor is the presence or absence of color and flavor forming Micrococcaceae bacteria, which are responsible for the sausage aroma. It should be pointed out that as the sausage slowly dries out, it loses moisture, but not the original amount of salt which remains inside. That will change the proportion of salt in regards to the new weight of the meat and the sausage will taste saltier. The truth is that this is hardly noticeable due to the bacterial action on proteins and fats which somehow cover up this saltiness.

The supermarket variety of semi dry sausages is made in a few days at the lowest cost possible. There is no time for flavor forming bacteria to start breaking proteins and fats; the rapidly dropping pH prevents them from doing so. During fermentation the main bacterial action is due to lactic acid bacteria which are producing lactic acid. The faster acidity is achieved, the faster the sausage becomes microbiologically stable and can be distributed into stores. This technology is popular in North Europe and especially in the USA.

Although we dislike the idea of liquid smoke, it can be used to impart a smoky flavor if a smokehouse is not available. Check the directions on the bottle but about a half teaspoon of liquid smoke to one pound of sausage is a typical dosage.

Without starter cultures it will be very risky to attempt making fast-fermented (semi-dry) sausages which will not be subsequently cooked, as the safety of this type of sausages relies heavily on a fast pH drop to 5.3 or less in about 48 hours. Without starter cultures such a fast pH drop is difficult to achieve unless Gdl is introduced.

Choosing Sausage Type

Choosing the sausage type is the first step as it determines fermentation and drying temperatures, total production time, amount and type of sugar used, type of starter cultures and other factors. By now you should realize that with one recipe you can make different sausage types (slow or fast-fermented) and it is entirely up to you which way you want to go. Twenty years ago a hobbyist had only one choice, and that was a slow-fermented sausage. Today, starter cultures are easily obtainable and all types of fermented sausages can be produced at home. Let’s say you have a recipe for a fresh Italian sausage and you want to make a fermented sausage out of it. All you need is to increase the percentage of salt, add sodium nitrite, starter culture and decide whether you want to wait 3 months before you can eat it, or whether you want to take it with you on a hunting trip that happens in one week time.

Classical dry fermented sausages are the hardest to manufacture. They also require the most time and care. Therefore, it is advised to start with semi-dry sausages first, which are faster, easier and safer to produce. After they are fermented, smoked and cooked they become great snacks, which can be taken everywhere. They can be left hanging in the kitchen and even though they will lose more moisture in time, they will still be safe to consume. Then, as more experience is gained, more difficult sausages can be attempted.

Adapting Known Sausage Recipes

There are many sausages, for example Soviet, Moscow or Tambov, which belong to the dry type of sausages. The meat was cured with salt and nitrate for 5-7 days at 40º F, 4º C, then cold smoked for 3-5 days (below 71º F, 22º C) and then dried for 25-30 days at 54-56º F, 12-14º C. Of course, no starter cultures were used. Those were naturally fermented sausages as the fermentation took place during the cold smoking stage. These sausages can be made faster today with starter cultures. They will also be much safer to produce at home conditions and of constant quality. By using different cultures or proper manipulation of the fermentation temperatures, the same sausage recipe can produce a semi-dry or dry sausage. Information presented in this chapter is by no means complete and should be thought of only as an introduction to the science of making fermented products. It is paraphrased from our book The Art of Making Fermented Sausages where a reader will find more detailed information on the subject.

The recipes are calculated for 1 kg of meat. This requires 0.12 g T-SPX starter culture or 0.25 g of F-LC, or LHP culture. A compact digital scale with an accuracy of 0.01 g is needed. Another solution is to make 5 kg of sausage at the time and the amount of culture may be estimated using a teaspoon: 0.6 g (¼ tsp.) of T-SPX and 1.2 g (½ tsp.) of F-LC.

Air Dried Sausages

Air dried sausages such as Spanish chorizo or cold smoked and then air dried sausages, conform to the same safety rules as fermented sausages. In many cases they are made without starter cultures and all safety hurdles as explained in this chapter must be obeyed. Fresh meat, processing at low temperatures, and a high percentage of salt and sodium nitrite will offer protection in the initial stages of production. Then as the sausage keeps on drying, it loses more moisture and becomes more stable in time. Needless to say, the production of fermented and air dried sausages require more skill and knowledge on the part of a sausage maker.

Equipment

To be able to precisely control temperature, humidity, and air speed requires expensive computer controlled drying chambers and a home sausage maker must use his ingenuity to come up with suitable solutions. Making fermented sausages at home definitely presents some difficulties, which we don’t have to face when making other types of sausages. It is very helpful to have a system capable of automated temperature and humidity adjustments, but those with limited funds will have to improvise a bit. Without a doubt the precise control of such a vast range of temperatures (50-104º F, 10-40º C) and humidity (60-95%) is not easy. There are no small drying chambers designed for home production of fermented sausages, and one has to assemble his own system. Commercial producers use huge rooms with air conditioning ducts supplying air at the right temperature, humidity and speed. There is a refrigerator in every kitchen and that appliance can be quite easily adapted for fermenting and drying sausages. A used refrigerator can be obtained everywhere and as long as it works it will fit our purpose. Most refrigerators are made with a separate freezer door which is normally located in the upper part of the unit. Well, this unit is not needed and will not become part of the system. If a one door refrigerator can be found it works even better.

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(after all that, and an omitted section about equipment etc. if you still want to go ahead, here is a recipe or two)

 

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Cervelat

European semi-dry sausage, an equivalent of American summer sausage. Definition covers countless recipes and sausages with the name cervelat made in many countries. You can call Thuringer, the Thuringer Cervelat, or Summer Sausage the Cervelat Summer sausage and both names are correct describing the same type of sausage.

(per 1000 grams of meat, or 2.2 pounds )

Meat                Metric                    US

beef                700 g                    1.54 lbs.

pork                300 g                    0.66 lbs.

Ingredients per 1000 g (1 kg) of meat:

salt, 2.5%

(salt in cure #1 accounted for)   23 g          4 tsp

Cure #1          2.5 g                       ½ tsp

dextrose (glucose) 10.0 g           2 tsp

sugar             10.0 g                    2 tsp

ground black pepper   3.0 g        1½ tsp

whole black pepper     2.0 g         1 tsp

coriander                   2.0 g           1 tsp

whole mustard seeds  4.0 g        2 tsp

ginger                       1.0 g          ½ tsp

F-LC culture            0.24 g          use scale

Instructions:

1. Grind pork and beef through 3/16” plate (5 mm).

2. Mix all ingredients with meat.

3. Stuff into beef middles or fibrous casings about 60 mm diameter, form 30” links.

4. Ferment at 38º C (100º F) for 24 hours, 90-85% humidity.

5. Introduce warm smoke (43º C, 110º F), 70% humidity, for 12 hours. Gradually increase smoke temperature until internal meat temperature of 60º C, 140º F is obtained.

6. For a drier sausage: dry for 2 days at 22-16º C (70-60º F), 65-75% humidity or until desired weight loss has occurred.

7. Store sausages at 10-15º C (50-59º F), 75% humidity.

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Salami Traditional

The following is the official Polish Government recipe for making traditional salami. When the war had ended, this recipe was used to make the salami that was sold in Poland to the consumers.

Meat

Metric

US

lean pork cuts

800 g

1.76 lbs.

pork back fat or fat trimmings

200 g

0.44 lbs.

Ingredients per 1000 g (1 kg) of meat:

salt, 3% (salt in Cure #2 accounted for)

28 g

5 tsp

Cure #2

2.5 g

½ tsp

sugar, 0.15%

1.5 g

⅓ tsp

pepper

2.0 g

1 tsp

garlic powder

1.0 g

⅓ tsp

or fresh garlic

3.5 g

1 clove

paprika

1.5 g

¾ tsp

Instructions:

1. Cut meat into 10 cm (3-4”) pieces and place in a slightly raised container with holes in the bottom to allow for draining of curing liquid. Leave for 24 hours at 1-2°C (33-35°F). Then grind with ¾” plate and leave for an additional 2-3 days following the above procedure. During that period turn meat around 1-2 times. Leave sheets of unsalted back fat for 2-3 days at -2° C (28° F) to -4° C (24° F) and then cut into 3 mm (⅛”) pieces.

2. Mix meat, back fat, salt, nitrate and spices together. Grind through 3 mm (⅛”) plate.

3. Leave the sausage mass for 36-48 hours at 2-4°C (35-40°F).

4. Stuff casings firmly. Do not add water. bad_boy any visible air pockets with a needle.

5. Hang for 2-4 days at 2-4°C (35-40°F), 85-90% humidity.

6. Smoke with thin cold smoke 16-18° C (60-64° F) for 5-7 days, until dark red color is obtained.

7. Hang in a dark, lightly drafty area at 10-12°C (50-53°F), humidity 90% for 2 weeks until salami develops white, dry mold on outside. If green and moist mold appears on salamis they have to be washed with warm salty water and wiped off dry with a cloth. Hang for 4-5 hours in a drier place, then move back to the original room and continue drying.

8. Place salamis covered with white mold for 2-3 months in a dark and lightly drafty area at 12-15° C (54-59° F), 75-85% humidity, until desired yield is obtained.

Notes:

In the original recipe 0.08 kg potassium nitrate was added to 100 kg of meat.

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Summer Sausage

Summer sausage is an American semi-dry fermented sausage, made of pork and beef, although sausages made from beef alone are common. The sausage was made in the winter time and after drying and storing it was consumed in the summer when working in the field. Summer sausage displays a long shelf life without refrigeration and is often used as a component of food for gift baskets along with different cheeses and jams. Diameter of casings varies from 40-120 mm and so does the length of the sausage.

Meat

Metric

US

pork

700 g

1.54 lbs.

beef

300 g

0.66 lbs.

Ingredients per 1000 g (1 kg) of meat:

salt, 2.5% (salt in Cure #1 accounted for)

23 g

4 tsp

Cure #1

2.5 g

½ tsp

dextrose (glucose), 1.0%

10.0 g

2 tsp

sugar, 0.5%

5.0 g

1 tsp

black pepper

3.0 g

1½ tsp

coriander

2.0 g

1 tsp

whole mustard seeds

4.0 g

1½ tsp

allspice

2.0 g

1 tsp

garlic

3.5 g

1 clove

F-LC culture

0.24 g

use scale

Instructions:

1. Grind pork and beef through 3/16” plate (5 mm).

2. Mix all ingredients with ground meat.

3. Stuff into beef middles or fibrous casings about 60 mm.

4. Ferment at 30º C (86º F) for 24 hours, 90-85% humidity.

5. Introduce warm smoke (43º C, 110º F), 70% humidity, for 6 hours. Gradually increase smoke temperature until internal meat temperature of 140º F (60º C) is obtained.

6. For a drier sausage: dry for 3 days at 22-16º C (70-60º F), 65-75% humidity or until desired weight loss has occurred.

7. Store sausages at 10-15º C (50-59º F), 75-80% humidity.

Notes:

Some sausages may contain around 10% diced cheddar cheese.

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Thuringer

Semi-dry partially or fully cooked, smoked beef and pork sausage.

Meat

Metric

US

pork

700 g

1.54 lbs.

beef

300 g

0.66 lbs.

Ingredients per 1000 g (1 kg) of meat:

salt, 2.5% (salt in Cure #1 accounted for)

23 g

4 tsp

Cure #1

2.5 g

½ tsp

dextrose (glucose), 1%

10 g

2 tsp

coriander

2.0 g

1 tsp

whole mustard seeds

2.0 g

1½ tsp

allspice

2.0 g

1 tsp

F-LC culture

0.24 g

use scale

Instructions:

1. Grind pork and beef fat through 3/16” plate (5 mm).

2. Mix all ingredients with meat.

3. Stuff into beef middles or fibrous casings 40-120 mm.

4. Ferment at 30º C (86º F) for 24 hours, 90-85% humidity.

5. Introduce warm smoke (43º C, 110º F), 70% humidity, for 6 hours. Gradually increase smoke temperature until internal meat temperature of 140º F (60º C) is obtained.

6. For a drier sausage: dry for 2 days at 22-16º C (70-60º F), 65-75% humidity or until desired weight loss has occurred.

7. Store sausages at 10-15º C (50-59º F), 75% humidity.

 

[KEN W]

This is a long though interesting read. Most of it won't be used at home vs commercial. I doubt anyone uses cure #2 and a long drying process to make sausage. I also doubt very few people can control temp, humidity and PH to do this. We don't have drying and curing rooms like commercial makers do to control these. I wonder if local butchers even have these available. I work in a large supermarket here where they make their own sausages. They don't make SS or Salami. Probably because they can't control these.

 

I have always wondered how you can put those small summer sausage sticks in fruit baskets w/o refrigeration. Now I know. So.....what have I learned. Type of sugar and salt can make a difference. What kind of fermenter should be added. When, where and how long should you allow the fermentation process to work. All this using a hot smoke at what temp. Can liquid or powdered smoke be used and at what ratio.

 

I have tried citric acid, buttermilk and Fermento to get the tangy taste. Citric acid was too harsh, buttermilk not enough and Fermento worked the best.BUT it isn't easily available and isn't cheap. Sausage Maker, Allied Kenco and Eldons sell it.

Edited November 21, 2016 by KEN W

[delcecchi]

In the book, in a part I left out, he talks about how to make a curing setup out of an old refrigerator.  

[Thunderbird]

It sounds complicated but it really isn't. You don't have to worry about humidity and cure  #2 unless you want a product that can be kept without refrigeration.Just make sure your recipe has enough dextrose to feed the bacteria in the F-LC culture. I found that keeping the sausage in a 90F. oven for about 12 hours before smoking to be about right.

[KEN W]

That is using citric acid?

[KEN W]

Do you use dextrose or sucrose (table sugar)?

 

Table salt or canning salt?

[Thunderbird]

Ken, no citric acid.Yes you mix in sucrose too. Go to Butcher and Packer and go to recipes and then American summer sausage. The Bactoferm(TM) LHP starter culture is the way to go. I will post the recipe that I like tomorrow. I make sourdough bread that uses the same principle to achieve a tart flavor. Supermarkets have sourdough bread that is made with citric acid and it is an inferior product compared to naturally fermented bread. If you are going to make home-made bread or sausage why would you take short-cuts?

[delcecchi]

Bread made with citric acid to taste sour isn't sourdough.   I don't care what the label says.  

[Thunderbird]

Tangy Summer sausage

10 lb.s meat  3/16  grind

2 tsp. cure#1

5 Tbs. salt

4.5 tsp. sugar

3 Tbs. dextrose

2.5 Tbs. mustard seed

1 Tbs.coriander

1tsp. ground ginger

1Tbs. black pepper

1 tsp. garlic powder

binder 25g. sodium phosphate or 1 cup dry milk or soy protein concentrate.

10 g.(about .5 tsp.) Bactoferm LHP available at Butcher and Packer

1 cup water

mix LHP with a little non-chlorine water stir well and let it sit for about 10 min.s

Add this mixture after mixing all the other ingredients.

Stuff the sausage and put it in a oven or smoker set at 90-100F.

Let the sausage ferment over night about 12 hr.s

set the smoker at 130F.-150F. and apply smoke for as long as you prefer

After you're done smoking, crank the temp. up to 180-200

When the internal temp. of the sausage reaches 152 it is done.

[Grainbelt]

9 minutes ago, Thunderbird said:

Tangy Summer sausage

10 lb.s meat  3/16  grind

2 tsp. cure#1

5 Tbs. salt

4.5 tsp. sugar

3 Tbs. dextrose

2.5 Tbs. mustard seed

1 Tbs.coriander

1tsp. ground ginger

1Tbs. black pepper

1 tsp. garlic powder

binder 25g. sodium phosphate or 1 cup dry milk or soy protein concentrate.

10 g.(about .5 tsp.) Bactoferm LHP available at Butcher and Packer

1 cup water

mix LHP with a little non-chlorine water stir well and let it sit for about 10 min.s

Add this mixture after mixing all the other ingredients.

Stuff the sausage and put it in a oven or smoker set at 90-100F.

Let the sausage ferment over night about 12 hr.s

set the smoker at 130F.-150F. and apply smoke for as long as you prefer

After you're done smoking, crank the temp. up to 180-200

When the internal temp. of the sausage reaches 152 it is done.

 

Thanks for the recipe, I already received my summer sausage mix from Curlys and now I think I will get some LHP and follow this. In the oven overnight and to the smoker, simple enough. I suppose the overnight in the oven would meld the cure and seasonings to the meat like overnight in the fridge?

[Thunderbird]

Yes. Make sure there is some dextrose in the mix.

[blue_healer_guy]

Thunder, any reason you switched from Donbos recipe?

[Thunderbird]

Bhguy, I don't remember Donbo's recipe.Please refresh my slowly failing memory.

[KEN W]

Your recipe only calls for 1/2 tsp of starter for 10 lbs of meat. That stuff must be potent. The smallest pkg from Butcher/packer  makes 500 lbs of sausage. And it says it  keeps for only 6 months frozen. I would be throwing almost all of it away after 6 months. I think I will stick with fermento, cultured buttermilk or citric acid. instead. I might just follow the rest of your recipe.

 

One other thing......placing the SS in a smoker at 90 degrees for 12 hours to allow it to ferment. I read in that LONG article above about fermenting that you can place the sticks in the fridge for 2-4 days before smoking and cooking. Lower temps of 40 degrees make the fermenting process slower. But it might be easier.

Edited November 23, 2016 by KEN W

[Thunderbird]

Ken, one pac of B&P LHP starter will make four ten pound batches. If you have a scale that measures grams just divide by 4. This recipe must be made the way I wrote it. Maybe you will have to make a couple batches to get it right but when you do it will be the best summer sausage you ever ate.My recipe without the fermentation is no better than what most other mixes produce.

Edited November 23, 2016 by Thunderbird

[KEN W]

Thunderbird, this is what it says on Butcher/Packer when buying LHP.......

 

Each 42-gram packet of LHP will do 500 pounds (225 kilo) of meat. You can use half of the packet in 100 pounds of meat, and refreeze remaining culture. Use al least 1/4 of the packet in any production under 100 pounds of meat.

Note: Cultures must be stored in freezer and has a shelf life of 14 days unrefrigerated and 6 months frozen.

 

These directions are hard to follow. It looks like there is a minimum to add, but it is up to you to figure out how much to add to get it as tangy as you want. That means a lot of experimenting. But no matter how much I would add.....I would have a lot left over to throw away.

 

So you are saying there are 2 tsp in a pkt??Your recipe says add a 1/2 tsp for 10 lbs. My size sticks are about 2 1/2 to 3 pounds . Using 1 tsp for 20 lbs and they last longer than 6 months, most of the culture would be thrown away.

 

I think I am missing something here. Their directions are really confusing. You are saying 1 pkt does 40 lbs. That is a lot different than what they are saying.

 

 

Edited November 23, 2016 by KEN W

[Thunderbird]

Ken see if this makes sense.

starter culture.oxps

[delcecchi]

What they said makes sense.  It is like making wine.   The fermentation is limited by the amount of sugar, not by the amount of culture.    When the bacteria turn all of the sugar into acid, they are done.  It probably happens somewhat faster or slower depending on how much culture is added and the temperature that it takes place.    The flavor is controlled by the amount of sugar, and to a  lesser extent the amount of culture is what I get out of that .

 

Using a larger dose might actually be good, since it seems as if it would be more likely to quickly overwhelm any unwanted bacteria.    The tricky part is getting the culture evenly distributed in the meat. 

 

 

[PurpleFloyd]

The biggest problem with the 90 degree holding period is that the electric smokers are not designed to hold that temp consistently and at least the newer ovens are the same way. 

I contacted Masterbuilt about my smoker not being able to consistently hold a temperature of 165 degrees and they sent the following:

 

 

Morning,

 

All of our smokers are designed to smoke at 200 or degrees. If you are trying to smoke below 200, we do offer a cold smoker attachment.

 

If there is anything we can further assist you with, please contact us.

 

Kind Regards,
Addie 

 

 

 

Masterbuilt Customer Service

 

 

I bought the cold smoker attachment and it still puts out enough heat to make it over 90 degrees in the summer. In the winter it might go lower but won't probably hold to a consistent temp. Our oven in the kitchen is digital and you can't program it to a temp less than 150 degrees. 

 

You can use the amazin tube smoker, the wedgie etc to make smoke but controlling the temp at 90 is something that I have not found the means to do without a lot of baby sitting. 

 

If I do get that part figured out I do want to try more cold smoking. 

[Thunderbird]

The pilot light in our oven keeps the temp. at around 90F. I wonder if a small cheap electric hot plate would work?

[KEN W]

OK.....it looks like you have to have a very controlled environment. Plus a specific amount of fermenter and sugar. To get it exactly right each time might be difficult. Plus you would have to experiment until you get it the way you want it. And it says unused should be kept only 6 months. I don't make big batches all at once. I prefer to make 10-20 pound batches every few months and use fresh meat. Rather than have a freezer full of sticks. I will just use encapsulated citric acid. Thanks for the help.

[delcecchi]

9 hours ago, PurpleFloyd said:

The biggest problem with the 90 degree holding period is that the electric smokers are not designed to hold that temp consistently and at least the newer ovens are the same way. 

I contacted Masterbuilt about my smoker not being able to consistently hold a temperature of 165 degrees and they sent the following:

 

 

Morning,

 

All of our smokers are designed to smoke at 200 or degrees. If you are trying to smoke below 200, we do offer a cold smoker attachment.

 

If there is anything we can further assist you with, please contact us.

 

Kind Regards,
Addie 

 

 

 

Masterbuilt Customer Service

 

 

I bought the cold smoker attachment and it still puts out enough heat to make it over 90 degrees in the summer. In the winter it might go lower but won't probably hold to a consistent temp. Our oven in the kitchen is digital and you can't program it to a temp less than 150 degrees. 

 

You can use the amazin tube smoker, the wedgie etc to make smoke but controlling the temp at 90 is something that I have not found the means to do without a lot of baby sitting. 

 

If I do get that part figured out I do want to try more cold smoking. 

 

 

How about a light bulb for heat?   Pick the right wattage, 25, 40, 60 etc.   Even a dimmer if necessary. 

 

Just lay it on the bottom of the smoker and run the cord out. 

[PurpleFloyd]

30 minutes ago, delcecchi said:

 

How about a light bulb for heat?   Pick the right wattage, 25, 40, 60 etc.   Even a dimmer if necessary. 

 

Just lay it on the bottom of the smoker and run the cord out. 

Sure,if you want to experiment with which wattage maintains 90 degrees at every temp between zero and 90 degrees and keep them on hand and then figure out how to keep from breaking the bulbs in there.

 

You could also use candles if you figure out how much candlepower it takes to do the same amount of work

[Thunderbird]

A light bulb is a great idea Delcecchi and PurpleFloyd, You could easily hang it in your oven and experiment with different bulbs until you find the right one.Temps are stable in your kitchen  and I'm sure you would have no problem maintaining the right temp.

Edited November 24, 2016 by Thunderbird

[PurpleFloyd]

So no candles then?