5 – MICROBIOLOGY-TECHNOLOGY          The Science Of Meat & Cultures

5 – MICROBIOLOGY-TECHNOLOGY The Science Of Meat & Cultures

Ya say you’re frightened by the latest news on ebola? Well, read on. The magical, microscopic world of Microbiology can be your friend, but if you aren’t careful, it can be your worst enemy.

 

Read. Post! Be merry, for tomorrow you… uh… live long and prosper, if you understand just a smidgen of this stuff. Please share those questions and answers with everyone else. You might say, we’re dying to know!

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93 thoughts on “5 – MICROBIOLOGY-TECHNOLOGY The Science Of Meat & Cultures

  1. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p.4)

    Bactoferm ™ Bacterial Cultures

    Now, where does Bactoferm™ fit in? The product is simply a high-quality, freeze-dried culture of controlled and measured bacteria in various strengths for slow, medium, or fast production. With Bactoferm™, the pH drop (increase in acidity) may occur in as little as 2 days to as much as several months. Other cultures are formulated to produce various, specifically desired qualities such as desired flaky-white mold formation (penicillium nagliovense) or even protection against listeria. Why do we use it? Simple! Uniformity and maximum positive effect; it’s foolproof!

    Why We Use Cure #2?

    In time, man’s discovery of nitrates in any number of the earth’s salt reserves, were found to assist in the curing process as micrococcus bacteria (usually staphylococcus) cause nitrates to break down into nitrites. Cure #2 (containing a “reservoir” of sodium nitrate) is used in dry-cured (fermented) sausages whenever curing time allows its sodium nitrate to gradually break down into sodium nitrite. Cure #2 in the United States, contains 6.25% sodium nitrite (NaNO2), 4% sodium nitrate (NaNO3), and 89.75 sodium chloride (salt). Why so much sodium nitrate as compared to that in Cure #1? As micrococcus bacteria (also called Kokuria) reduce nitrate to nitrite, nitric oxide is produced. It is actually this element that “cures” meat. Following two weeks dry-curing, only about a quarter of the 6.25 % sodium nitrite remains in meat. Nitrite simply breaks down too quickly to be of value over an extended period. In other words, in salamis requiring three or more months to cure, a certain amount of sodium nitrate must be added to break down into yet more nitrite over time.

    (Continued next post)

  2. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p.5)

    Bad Bugs With Bad Manners!

    Bacteria In Sausage Making

    Although sausage makers deal with three types of bacteria, (pathogenic, beneficial, and spoilage), we must also be aware of other dangerous microorganisms including yeasts and molds.

    Another consideration of sausage makers is non-bacterial. Some retain “tough-to-get-rid-of” toxic spores. Other microorganisms we may encounter are even non-bacterial, but actual living organisms such as trichinella spiralis – a microbial, nematode worm!

    Each year in the United States food borne diseases cause approximately 76 million illnesses and 325,000 hospitalizations*. Of this number, more than 5,000 Americans painfully suffer the clearly evident indications and symptoms of preventable food contamination, breathe their last breath, and agonizingly die!
    √ (* statistics from Center For Disease Control )

    Three pathogens in particular – Salmonella, Listeria, and Toxoplasma – are responsible for 1,500 deaths annually. Many of the pathogens of greatest concern today were not even recognized as causes of food borne illness merely twenty years ago! They include Campylobacter jejuni, Escherichia coli O157:H7, Listeria monocytogenes, Cyclospora cayetanensis, and others.

    Other pathogenic bacteria of concern to sausage makers include Clostridium botulinum whose spores produce the deadliest toxin known to man, and Clostridium perfringens – both of which grow without oxygen present. Staphylococcus aureus is present in the mouth, nose, and throat as well as on the skin and hair of many healthy people who never suspect it. One cough or sneeze may be accountable for the sickness of countless individuals. Shigella, also a rod-shaped pathogenic bacterium, is closely related to E.coli and salmonella. Usually ingested, it is the cause of severe dysentery. Also rod-shaped pathogens of bacteria genus bacillus include Bacillus cereus, which causes a foodborne illness similar to that of staphyloccus.

    We live in a microbial world in which there are limitless opportunities for pathogenic or spoilage microorganisms to contaminate food whether it is produced in huge commercial kitchens or prepared “from scratch” at home. Food borne microbes are present (usually in the intestines) in healthy animals raised for food and the slightest contact with even small amounts of intestinal contents may contaminate meat or poultry carcasses during slaughter. Others are passed along by any number of means. As a result, worldwide each year, over two million people die from diseases attributed to contamination of food and drinking water, many being painful diarrheal diseases. Even in industrialized countries, up to 30% of the population has reported suffering from food borne diseases annually.

    Recently in Europe, two and a half million pounds of beef were recalled due to salmonella contamination. In the United States, a single ice cream producer affected 224,000 persons when salmonella contaminated products were placed on the market. Earlier, an outbreak of hepatitis A, resulting from the consumption of contaminated clams, affected some 300,000 individuals in China. In the United Kingdom, two million cases, (about 3,400 cases per 100,000 inhabitants), of food contamination are reported each year. In France, three quarters of a million people (1,210 cases for 100,000 inhabitants), report food contamination sicknesses annually. Australia reports an estimated five and a half million cases of food-borne illness every year, causing 18,000 hospitalizations and 120 deaths. The problem creates an enormous social and economic strain on people in every country. In the United States alone, diseases caused by the major pathogens are estimated to cost over $35 billion dollars annually in medical costs and lost productivity.

    (Continued next post)

  3. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p.6 )

    So, why am I including this ghastly information in the midst of our sausage making project? Frankly, to scare the daylights out of you! What better place to print explicit and even graphic details in which every responsible sausage maker should become familiar before undertaking the business of feeding or preparing sausage for other people? A trusted sausage maker or cook may either promote or recklessly endanger the health of other human beings. I openly cringe whenever I hear someone repeat the words “he’s just a cook”. Inside our ranch kitchen, cowboys helped with dishes and treated the cook as if he were royalty. After all, although he was “just the cook”, all hands depended upon the “biscuit wrangler” to feed us fresh, tasty, and safely prepared food. Shucks pards, we all knew he could have easily slipped a little something extra into the chocolate pudding anytime he had revenge on his mind. We also trusted and relied upon him to help keep harmful bacteria out of the sausage and meat products we devoured like hungry wolves.

    Safety n’ Savvy

    Before you begin making sausages in your own ranch or home kitchen that others will consume, you MUST become familiar with the basics of food handling safety and gain at least a fundamental insight of microorganisms and their behavior. Without this knowledge, you may very easily harm someone most seriously. Making fresh sausage involves the use of immaculately clean utensils and low processing temperatures. We must take advantage of every opportunity to lower the temperature of the meat during the various steps of processing sausage. Those of the cured, cooked, and smoked variety, require the same essentials, but further include the use of sodium nitrites and nitrates, higher salt content, and of course, higher cooking temperatures. If you wish to make any type of dried or semi-dried sausage, a basic understanding of the fermentation process becomes necessary, along with an elemental knowledge of unique, acid-producing, microorganisms and their behavior. In other words, because the meat in these sausages is not cooked during preparation or even upon consumption, a bit more “bacteria savvy” is required. Further, in making those great tasting, tangy, “fermented” sausages, familiarity with a few unique safety procedures involving yeast and mold microorganisms is essential. They include at least an elemental understanding of:

    1. Water activity (Aw) – a measure of how much “bound” water is available to microorganisms.

    2. pH acidity – (potentiometric hydrogen ion concentration) – a measure of acidity or alkalinity in food, developing resistance against microbiological spoilage.

    3. Microbiology, including:
    a. molds
    b. yeasts
    c. bacteria of three types:
    1. pathogenic
    2. beneficial
    3. spoilage

    (Continued next post)

  4. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p. 7)

    The Major Causes Of Food Poisoning

    1. Pathogenic Bacteria

    Of the three microorganisms affecting food (bacteria, yeasts, and molds), pathogenic bacteria, existing virtually everywhere in our environment, remain the greatest cause of food poisoning. Sausage makers and food handlers must be aware of the strains of (a.) food spoilage bacteria, (b.) pathogenic bacteria, and (c.) beneficial bacteria. Millions of microbes may be found on unwashed hands and dirty utensils and under the right conditions, multiply at an alarmingly incredible rate.

    As sausage makers, we must constantly be aware of the primary factors necessary for bacterial growth. We must also know how to change any dangerous circumstances immediately. Bacteria need merely four elements for growth:

    (1.) moisture- Did you ever imagine that meat is comprised of three-quarters water? If we freeze the water in meat, we give it temporary defense against bacteria by “binding” the moisture. Moisture is the primary reason meat spoils. Will dehydrating meat preserve it? We’ve been doing just that for thousands of years!

    (2.) nutrient- Meat, (mammalian muscle) consists of roughly 75% water, 19 % protein, 2.5% fat, 1.2% carbohydrates, and 2.3% non-protein substances such as amino acids and minerals. Exposed to the atmosphere, meat becomes a virtual feast for bacteria.

    (3.) warm temperature- Bacteria thrive at body-temperature! Called the “danger zone”, the range from 40°F. (4°C.) to 140°F. (60°C.) is the optimum temperature periphery for bacteria to multiply. It is interesting to note that bacteria are restricted from growing at 130°F. (54°C.) but actually start to die at 140°F. (60°C.).

    (4.) lack of oxygen- Aerobic bacteria need oxygen; anaerobic bacteria do not. Certain pathogenic bacteria in sausage being smoked certainly present a risk. Casings also cut off a certain volume of oxygen as does the “overnight curing” covered with plastic wrap inside a refrigerator. Remember the first rule of sausage making: Don’t smoke it if you can’t cure it! (meaning the use of actual cures of sodium nitrate or sodium nitrite).

    Bacteria, have been named mostly in Latin or Greek, for their shape. Spherical bacteria are called cocci. Rod-shaped bacteria are known as bacilli. Curved bacilli (resembling a comma), are called vibrio. If they are spiral-shaped, the are called spirilla, and if the bacilli is tightly coiled, it is called spirochaetes. Many bacteria exist simply as single cells. If they are found in pairs, they are neisseria. The streptococcus form chains while the staphylococcus group together in clusters resembling grapes.

    If a specific bacterium is a facultative anaerobic, it is most active in oxygen but can survive without it. On the other hand, an obligate anaerobe cannot grow in the presence of oxygen. Bacteria do not grow in size – they multiply in number. And they do it very quickly! Without oxygen, the addition of sodium nitrates or sodium nitrites is necessary to prevent botulism. It also becomes crucial that meat be removed from the “danger zone” temperature range as quickly as possible during any preparation or cooking process. This includes grinding, mixing, and stuffing sausages, procedures often supported using ice, ice water, or refrigeration and freezing. As bacteria need moisture to multiply and meat is about three-quarters water, it becomes an ideal environment for the growth of bacteria, even when it is mostly dried. However, there is a point in which meat can lose so much “available” water, it will no longer sustain bacteria. This point differs within each particular type bacterium. We’ll discuss this “water activity” later as well as another bacteria destroying process known as potentiometric hydrogen ion concentration… or simply “pH acidity”.

    (Continued next post)

  5. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p.8 )

    Our first line of defense continues to be the application of extreme temperatures applied to meat either being cooked or frozen. As sausage is prepared, it is essential to work with only small batches at a time outside the refrigerator. Very often, meat is partially frozen before it is put through a grinder and bacteria at this temperature remain mostly inactive. In the grinder, ice chips are sometimes added to keep the temperature down as the friction of grinding actually warms the meat. Out of the refrigerator, most bacteria begin to wake up as the temperature rises above 40°F. (4.4°C.). At 50°F. (10°C.), it is safe to work with the meat only temporarily before it goes back into the refrigerator. At this point, salt in the amount of 2.5% – 3% is frequently added to partially restrict pathogenic and spoilage bacteria growth, as beneficial bacteria go to work producing protective acidity within time. Most bacteria thrive at the temperature of our bodies (98.6°F. / 36.6°C.). As temperatures rise much above the “danger zone”, their growth becomes restricted until around 140°F. (60°C.), they begin to die. Yet, strains such as Clostridium botulinum, may survive heating up to 250°F. (121°C) by producing heat-resistant, isolating envelopes called spores – nature’s way of protecting the organism by sheltering the bacteria from other unsympathetic environmental conditions.

    Clostridium botulinum – The Killer

    Clostridium Botulinum is a common obligate anaerobic bacterium microorganism found in soil and sea sediments. Although it can only reproduce in an oxygen-free environment, when it does reproduce, it produces the deadliest poison known to man – botulinum toxin. One millionth of a gram ingested means certain death – about 500,000 times more toxic than cyanide. Onset of symptoms can occur quickly and include nausea, stomach pain, double vision, and spreading paralysis, ultimately reaching the heart or respiratory organs. If treatment is given and the dose is low, half of those affected may survive, but recovery may take months or years. Although fatalities occur yearly, especially in countries where home canning is popular, the risk of acquiring botulism is very, very low. However, the lethal consequences of poisoning may make you wish to reconsider the proper addition of sodium nitrate/nitrite in your products to almost eliminate the risk. Worldwide, there are about 1000 cases of botulism each year.

    The rod-shaped bacterium was first recognized and isolated in 1896 following the poisoning of several people who had consumed bad ham. It was later discovered that due to the enzyme superoxide dismutase, the bacterium might actually tolerate very small traces of oxygen. Botulinum spores are extremely persistent and will survive heating up to 250°F. (121°C), freezing, smoking, and drying. Insidiously, they lie in wait for the right conditions to occur and give no foul smell or taste, making it even more treacherous. In non-cooked fermented sausages, the microorganism must be destroyed using a combination of salt, a drop beyond 5.0 pH, and a minimum drop in Aw water activity to 0.97 or less. Placing fresh vegetables or un-sterilized (garden fresh) spices into sausage is not recommended as botulinum spores are not uncommon on leafy herbs, peppers, beans, chilies, and corn. Cut off from oxygen by being stuffed into casings and placed in a smoker, the smoking temperatures are ideal for bacteria growth. The risk using fresh garlic is less, but cases of botulism poisoning have been reported after people have eaten home-canned garlic cloves in oil – the ideal environment for anaerobic bacterial growth!

    (Continued next post)

  6. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p.9 )

    The most commonly recognized foodborne infections are those caused by the bacteria species campylobacter, salmonella, and E.coli, along with a group of viruses called clicivirus also known as the Norwalk and Norwalk-like viruses. Campylobacter remains the most common bacterial cause of diarrheal illness in the world and incredibly, most raw poultry meat has campylobacter on it. Salmonella is also a bacterium widespread in the intestines of birds, reptiles, and mammals. Its infection, known as samonellosis, typically includes fever, diarrhea, and abdominal cramps. E.coli 0157:H7 is a bacterial pathogen infecting cattle and other similar animals. Human illness typically follows consumption of food or water that has been contaminated with microscopic amounts of cattle feces. The illness it causes is often a severe and bloody diarrhea with painful abdominal cramps, but without much fever. In 3% to 5% of cases, a complication called hemolytic uremic syndrome (HUS) can occur several weeks after the initial symptoms. This severe complication includes temporary anemia, profuse bleeding, and kidney failure.

    Norwalk and Norwalk-like virus (calicivirus) is an extremely common cause of foodborne illness, though it is rarely diagnosed, because its laboratory test is not widely available. It causes an acute gastrointestinal illness, usually with more vomiting than diarrhea, that resolves within two days. It is believed that Norwalk-like viruses spread primarily from one infected person to another. Infected kitchen workers can contaminate a salad or sandwich as they prepare it, if they have the virus on their hands. Infected fishermen have contaminated oysters as they harvested them. Sausagemakers, wash your hands!

    Although other routes usually transmit them, some common diseases are occasionally produced by foodborne bacteria. These include infections caused byshigella, hepatitis A, and the parasites giardia lambia, and cryptosporidia. Even “strep throats” have been transmitted occasionally through food.

  7. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p. 10)

    Indeed, we live in a microbial world with countless opportunities for food to become contaminated as it is produced and prepared. Many food borne microbes are present in healthy animals (usually in their intestines) raised for food. In the kitchen, microbes may be transferred from one food to another food by using the same knife, cutting board or other utensils to prepare both without washing the surface or utensil in between. Worse, a food that is fully cooked can become re-contaminated if it touches other raw foods or drippings from raw foods that contain pathogens.

    A “strain” is a sub-group within the species of a particular bacterium having unique characteristics distinguishing it from other strains. These differences are often detectable only at the molecular level; yet, they may result in changes to the physiology or lifecycle of the bacterium. Some strains develop pathogenic capacity becoming hostile to our food supply.

    Many bacterial microbes need to multiply before enough are present in food to cause disease. The way food is handled after it is contaminated can also make a difference in whether or not an outbreak occurs. Given warm moist conditions and an ample supply of nutrients, merely one reproducing bacterium dividing itself every half hour can produce 17 million progeny in only 12 hours! As a result, lightly contaminated food left out overnight can be highly infectious by the next day. If the food were refrigerated promptly, the bacteria would not multiply at all. In general, freezing prevents nearly all bacteria from growing but merely preserves them in a state of “suspended animation”. However, this general rule has a few surprising exceptions. Two foodborne bacteria, listeria monocytogenes and yersinia enterocolitica can actually grow at refrigerator temperatures! As we shall see, high salt, high sugar, or high acid levels keep bacteria from growing, which is why salted meats, sweetened jam, and pickled vegetables are traditionally preserved foods.

    (Continued next post)

  8. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p. 11)

    Staphylococcus Aureus

    Staphylococcus aureus is a particularly infamous nasty strain of bacteria that thrives at 98° Fahrenheit, causes intense vomiting, and much like clostridium botulinum, it is capable of producing toxins that remain in meat even after the microorganism is destroyed or removed. Most often found around the nose and throat or on sores, the foods most often contaminated with staphylococcus are moist and high in protein, such as meats and cheeses. The bacteria are usually passed onto food by the hands. “Staph” is even more dangerous because there is no tangible way to tell if meat is infected – taste, aroma, and appearance all seem normal. Moreover, it is highly resistant to drying and in the presence of oxygen, it can survive in Aw water levels down to an incredible 0.86. Worse, it can withstand a whopping 15% salt! Proper temperature management is essential – no, it is critical – in avoiding the spread of staphylococcus microorganisms. Cooked foods that are not cooled quickly enough or that are allowed to stand at room temperature are susceptible to infection. In fermented (not cooked) sausage, a rapid drop to less than 5.3 pH is required for its demise. In fresh or smoked-cooked-cured sausage, normal cooking temperatures exterminate the bacterium.

    E. coli

    The rod-shaped, facultative anaerobic, E. coli (escherichia coli) bacteria are comonly but not always confined to the lower intestine of warm-blooded organisms. Most are harmless and one strain in particular has been used in the development of probiotic medicine developed to treat gastrointestinal infection. However some strains, such as serotype 0157:H7, 0104:H21, and 0121, can cause potentially lethal toxins. The strain 0157:H7 especially may cause serious food poisoning in humans, as well as other life-threatening complications. The ability of E.coli bacteria to survive for brief periods outside the body makes them ideal candidates for fecal contamination. The bacteria survive freezing and acidic environments down to 4.0 pH and a minimum drop in Aw water activity to 0.95. Untreated water, unwashed hands, flies, or vermin can then spread the bacteria. As plants are eaten, the cycle continues. As with staphylococcus aureus, it is best destroyed using heat.

    Salmonella

    Salmonella bacteria do not produce spores, are not destroyed by freezing, and are facultative anaerobic, meaning they are active in oxygen but can survive without it. This is the nasty bug that causes Typhoid Fever! In food, it is the cause of salmonellosis. The rod shaped bacteria live in the intestinal tracts of humans and animals and are passed in the excreta of an infected host. Untreated water, unwashed hands, flies, or vermin can then spread the bacteria. Salmonella can survive for weeks outside a living body and have even been found in dried excrement after nearly three years. The foods most commonly infected with bacteria are poultry, eggs, and all kinds of meat. Thorough cooking of these foods at a temperature of at least 165°F. (74 ºC) will destroy the salmonella bacterium. Each year, about 40,000 Americans are infected with food borne salmonella and develop salmonellosis. Amazingly, another 142,000 are annually infected with Salmonella enteritidis solely from consuming raw chicken eggs! About 30 die. In non-cooked fermented sausages, the microorganism must be destroyed using a combination of salt, a drop to less than 3.8 pH, and a minimum drop in Aw water activity to 0.94.

    (Continued next post)

  9. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p. 12)
    Clostridium Perfringens

    Clostridium perfringens bacteria, like salmonella, is present in the intestines of humans and animals, but like clostridium botulinum, it is an obligate anaerobic and cannot grow in the presence of oxygen. The bacteria forms spores that survive very well in soil – thus vegetables may carry the organisms.Clostridium perfringens bacteria are most commonly found in raw foods, especially meats and poultry, and proper temperature management is fundamental in avoiding the spread of the microorganisms. In non-cooked fermented sausages, the bacteria must be destroyed using a combination of salt, a drop to a point less than 5.5 pH, and a minimum drop in Aw water activity to 0.93.

    Listeria Monocytogenes

    In October 2002, a major poultry producer in Franconia, Pennsylvania, recalled more than twenty-seven and a half million pounds of turkey and chicken “ready to eat” products they had already placed on the market. Following an outbreak of listeriosis, several other meat companies voluntarily shut down operations until the source could be identified. Unfortunately, listeria infection (listeriosis) in several northeastern states had taken its toll, initiating several deaths, sicknesses, miscarriages, and stillbirths.

    Each year in the United States, an estimated 2,500 persons become seriously ill with listeriosis. Another 500 die, causing listeriosis to be the leading cause of death from food borne bacterial pathogens! Twenty to thirty percent of infections result in death! Listeriosis infection is caused by eating food contaminated with the bacterium Listeria monocytogenes. Pregnant women are twenty times more likely to contract listeriosis than other healthy adults and account for a third of all reported cases. The elderly, and persons with weakened immune systems due to cancer, diabetes, kidney disease, and other diseases, are especially at risk.

    The rod-shaped Listeria monocytogenes bacteria do not produce spores and are found in soil and water. Most often, the bacteria get into food using manure as a fertilizer from animals having the infection yet displaying no ill symptoms. The bacterium is destroyed by heat while cooking or preparing food. Uncooked meats and vegetables and unpasteurized (raw) milk or foods made from unpasteurized milk may contain the listeria monocytogenes bacteria. Foods to be concerned about include soft cheeses and cold cuts at the deli counter, and many ready-to-eat foods such as hot dogs and raw vegetables. These items must be thoroughly cooked until they are steaming hot! Check the labels on Feta, Brie, and Camembert, any blue-veined cheeses, and Mexican cheeses such as Queso Blanco, Queso Fresco, and Panela. Unless labels clearly state they are made from pasteurized milk, avoid them. It is always a good idea to eat smoked seafood only in cooked dishes such as casseroles.

    Whenever making fresh sausage from any raw meat, protection from listeria monocytogenes is dependent upon cooking the meat until the recommended internal meat temperature of at least 152°F. (66.6°C.) is reached. In non-cooked fermented sausages, the microorganism must be destroyed using a combination of salt, a drop to less than 4.4 pH, and a minimum drop in Aw water activity to 0.92. Sausage making is completely safe only when the rules are stringently followed.

    (Continued next post)

  10. You Can Make Your Own Professionally – Fermented “Dry-Cured” Sausage! (p.13 )

    Campylobacter Jejuni

    It is now estimated that half of the chickens produced in America contain the spiral rod-shaped campylobacter jejuni microorganism that infects 13 persons in one hundred thousand. The bacterium does not produce spores. World wide, it affects about two and a half million people annually or 0.8% of the population. Most people who become ill with campylobacteriosis get diarrhea, cramping, abdominal pain, and fever within two to five days after exposure to the organism. The diarrhea may be bloody and can be accompanied by nausea and vomiting. The illness typically lasts one week. Although comparatively few people die from the disease (about 125 each year), the symptoms are harsh and painful, usually requiring medical attention. Many chicken flocks are infected with campylobacter but show no signs of illness. In non-cooked fermented sausages, the microorganism must be destroyed using a combination of salt, a drop to less than 4.9 pH, and a minimum drop in Aw water activity to 0.98. Campylobacter may be easily spread from bird to bird through a common water source or through contact with infected feces. When an infected bird is slaughtered, campylobacter organisms are easily transferred from the intestines to the meat.

    Shigella

    Reactive arthritis is autoimmune condition that develops in response to an infection in another part of the body. People developing an infection having come into contact with Shigella bacteria, often devolp severe dysentery and reactive arthritis. Infection is made though fecal-oral contamination and as few a ten cells may trigger the disease shigellosis. The rod-shaped bacterium does not produce spores, is closely related to E.coli, but is found naturally only in man and apes. It does not affect other animals. In non-cooked fermented sausages, Shigella bacteria must be destroyed using a combination of salt, a drop to less than 4.0 pH, and a minimum drop in Aw water activity to 0.91.

    Bacillus cereus

    Bacillus cereus is a rod-shaped bacterium that develops spores. Some strains are harmful to humans when survival of bacterial endospores takes place whenever food is improperly cooked. This problem is compounded when food is then improperly refrigerated, allowing the spores to germinate. Infection causes severe nausea, vomiting, and diarrhea. In non-cooked fermented sausages, bacillus cereus must be destroyed using a combination of salt, a drop to less than 4.3 pH, and a minimum drop in Aw water activity to 0.91.

    Other strains of bacillus cereus can be beneficial as probiotics. The bacteria are facultative anaerobic (most active in oxygen but can survive without it) and are found mostly in the soil. The bacterium is difficult to identify, as it closely resembles staphylococcus aureus and other pathogens. Bacillus cereus is also known to cause problematic skin infections in humans that can be quite damaging, and difficult to eradicate.

    (Continued next post)

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