Post
by Chuckwagon » Sat Sep 15, 2012 07:43
Hi Folks. I hope you are enjoying Project B and learning more about sausage and how to develop your skills. You`ve reached a point where it becomes necessary to learn a little about microorganisms if you are going to make safe sausage. Occasionally, during my lifetime, I`ve run across someone who totally disregards the safety rules. A few people I`ve talked to simply have no interest in learning about bacteria and other microorganisms that could spell real trouble. These people want to grind meat and enjoy sausage, but they don`t want to gain a basic knowledge of "bugs". Why? Two reasons actually. First, some say they don`t have time to learn about bacteria and rules. Second, many believe they have been out of school too long and they don`t wish to discuss microbiology just to be able to "grind a dang sausage". Sobeit! However... these people should never, and I mean NEVER, make a sausage that someone else will consume. If a person wishes to ignore the rules and disregard knowledge, he takes the risk of contracting diseases such as listeria, botulism, and even trichinosis, not to mention many others. However, if he allows someone else to consume his product, he might be facing litigation and in my opinion, he is liable.
I`ve chuckled and snickered at Kjuncatman`s `signature` on our forum since the first day I read it. It reads,"Cure the meat? Is it sick?" It doesn`t require a degree in microbiology to be able to understand this stuff, but it does require a little "sausage savvy". And it`s not complicated if it is explained correctly. I`d like to be the one to try to explain it to you... if you will allow me to do so. And please remember, there is no such thing as a silly question, so don`t hesitate to ask. If I don`t have an answer, I`ll find you one!
Lets talk about TWO ways of making safe sausage. First, you`ve got to know a little about microorganisms, especially "pathogenic" and "spoilage" bacteria. A third type of bacteria is called "beneficial bacteria" and indeed, we`ll use those too, in making good sausage. Besides bacteria, there are two other types of microorganisms to be concerned with in the sausage-making world. These are yeasts and molds. More about them later.
When I first started to study pathogenic bacteria, it didn't take me long to realize that perhaps nature may be just a bit forgiving as it is truly a miracle that man has not completely wiped himself out somehow in his carelessness with food-borne bacteria. Just one look into a microscope and some of this stuff will have you shaking in your boots! Incredibly, only a small number of pathogenic bacterial strains cause the millions of cases of food-borne illness each year and ironically, proper cooking or processing could prevent nearly all of them. The most dreadful is the notorious clostridium botulinum - the killer. Then there are the campylobacters. One genus, known as "jejuni" - has an infection that just makes us wish we were laid to rest. And then there is Clostridium perfringens - called the "cafeteria bug" because so many cases have been reported from foods left on steam tables or at room temperature for long periods. Did you know that there are over 1600 types of salmonella although we hear about salmonella enteritidis most of the time because it`s the bug found in some raw and undercooked eggs. Then there are staphylococcus aureus, streptococcus A, (found in the ears, throat, nose, blood etc. of humans), and shigella of 30 types, transferred to food mostly through human contact. Listeria monocytogenes and escherichia coli 0157:H7 are two more nasty critters we could do without. There are also two non-bacterial, parasitic types of organisms causing us great concern, and knowing how to destroy cryptosporidium paryumand and tricinella spiralis is imperative. Later, we`ll read more about sub-zero temperatures for treating meat for these "nematode worms". Right now, let`s destroy some bacteria!
Battling Bugs By Restricting Their "Available Water"
Okay, allow me to ask a question. If the world were depending upon you to eliminate pathogenic (disease causing) bacterial microorganisms, just how would you go about it? Can you think of the cheapest, most practical, or effective means to snuff `em out? You could starve `em out couldn`t you? If you dried up their food, they would expire... right? We know that bacteria cannot survive in an environment without moisture, so might it be possible to limit the amount of water available to bacteria in order to destroy them? And what about salt? What does it do and how much would you use? All good questions! However, contrary to popular certainty, salt does not destroy bacteria. It doesn`t even force water to evaporate. It does, however, immediately immobilize or bind a specific, large amount of free water, preventing it from interacting with bacteria (or anything else). The measurement of "bound" water (not available to bacteria) is called "water activity", and is abbreviated Aw. Water Activity is measured on a scale from 0.00 (called "bone dry") to 1.00 - the measurement of pure water. So, how about serving a bacterium a dose of salt at first, while we deprive it of moisture? It works. For thousands of years it has worked! Bacon, hams, sausages, and all sorts of meat have been cured with salt, smoked, and dried safely for centuries. Your grandparents certainly knew that salting, drying, and par-cooking meats were positive steps adverse to microorganism survival! They were also aware that if they smoked meat, it not only tasted better but it was not likely to develop mold on its surface.
pH - The Measure Of Acidity
Another effective means of reducing numbers of bacteria is to introduce them to an acidic environment. Have you ever thought about just how many foods we preserve in vinegar? In preserving sausage, we simply introduce a lactic acid - producing bacteria such as lactobacillus or pediococcus. Of course, acidity affects flavor and the addition of an acid is not just a simple solution for every type of meat. Yet, without lactic acid - producing bacteria, we wouldn`t have wonderful, tangy, fermented type sausage.
Okay, now don`t be afraid of a couple of big words. You don`t even have to remember them or spell them... if you remember their abbreviation. In chemistry, potentiometric hydrogen ion concentration is abbreviated pH. What's this? Shucks pards, I "aced" college chemistry... mostly because I intimidated the teacher with my garlic jerky breath! (I also threatened to ride my horse inside his classroom). Uhhh... Roughly, pH is the measurement of acidity or alkalinity in any substance using a scale from zero to fourteen. Pure water is said to be very close to neutral, having a pH measurement of nearly 7.0 at 77° F. Foods with pH less than 7 are said to be acidic, while foods having a pH greater than 7 are said to be alkaline or "base". Note that as we lower the pH factor, we increase acidity. Now, the big question. Are microorganisms able to survive inside acidic foods? Not when the acidity is increased in a sausage by a drop below about 4 pH., depending upon the specific microorganism we are referring to. Some are more resilient than others.
Lets investigate a most effective way of preserving non-cooked, fermented sausages such as salami and pepperoni, using lactobacillus or pediococcus - the bacteria that produces lactic acid when nourished with a sugar (powdered dextrose). For centuries, man has been able to make dry-cured sausage safely only because the meat he used was subjected to a long drying process (including large amounts of salt), as well as naturally occurring lactobacilli or pediococci bacteria found in the atmosphere and on the premises of the slaughterhouse or sausage maker. Of course, he did not realize why safe fermentation occurred, only that it did occur. Few families were privy to the processing information someone had previously, accidentally discovered, and had passed down for generations. Certainly, these families marketed their product as being "handcrafted" using "secret" information and recipes. Often a technique called "back slopping" was used, in which a small amount of a previous batch (containing lactobacilli) was introduced into a fresh batch of sausage. Civilizations throughout Europe employed this inoculating procedure, again not understanding the reason it worked - only that it did work. For the first time, sausages did not have to be cooked to be safely stored for any amount of time at room temperature.
Just what was taking place without the knowledge of the sausage maker? What mysterious force was rendering the sausage safe rather than being spoiled during the long process? Incredibly, the scientific secrets would not be entirely understood until the middle of the Twentieth Century! In short, man began to realize that as sausage "cures", a competition ensues between the good bacteria and the bad, both struggling for the same nutrition source. Time, (allowing lactobacilli or pediococci to accomplish their pH drop by increasing the acidity), becomes vitally important as the only initial protection of an air-dried sausage is the addition of salt, which immediately lowers the amount of "available water" accessible to any bacteria.
Again, salt does not destroy bacteria, nor does it cause water to evaporate. It does, however, limit the amount of water available to bacteria - with much the same effect that freezing accomplishes. (As ice crystals develop inside meat cells, they simply limit the water available to bacteria - prohibiting bacteria from becoming nourished.)
So, to sum it up, as sausages become slowly dehydrated in a controlled, humid, atmosphere or chamber, they become safe for consumption as pathogenic and spoilage bacteria are not able to survive, once limited available water restricts their nutrition. While this is going on, lactobacilli or pediococci bacteria are slowly producing lactic acid to also limit pathogenic and spoilage bacteria. Given the proper amount of time, both these procedures work very well in making that great tangy sausage we call "dry cured" or fermented sausage.
Now, where does Bactoferm™ fit in? The product is simply a high-quality, freeze-dried culture of controlled and measured bacteria of various species, 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 lactobacillus curvatus and pediococcus acidilactici for protection against listeria.
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.
Okay pards! `Nuff fer now. I hope you are able to understand my explanation. If you are having trouble, please re-read it and write down any questions that come up while you are reading. Thanks for bearing with me.
Best Wishes,
Chuckwagon
If it looks like a duck, walks like a duck, and quacks like a duck, it probably needs more time on the grill! 
Alas, if she saw my mustache and how it sort of makes me look like Mel Gibson,... (ahem, ahem...) she would probably throw over ol' JB in a minute and move out west! 
