Wisconsin Public Television Wednesday Nite at the Lab  The Science & Art of Sausage Making Jeff Sindelar  May 9,2012 UP722 >> Welcome, everyone, to Wednesday Nite at the Lab. I'm Tom Zinnen. I work here at the UW Biotechnology Center. I also work for UW Extension Cooperative Extension, and on behalf of those folks and our other partners, Wisconsin Public Television, the Wisconsin Alumni Association, and the Science Alliance here at UW Madison, thanks for coming to Wednesday Nite at the Lab. We do this every Wednesday night, 50 times a year. Tonight it's my pleasure to be able to introduce to you Jeff Sindelar. He's an assistant professor and Extension meat specialist in the Department of Animal Sciences here at UW Madison. He received a bachelor of science in animal science with a meats emphasis from the University of Nebraska Lincoln in 1999. Then he got a master of science in animal science and meat science from Michigan State University in 2002, and he got his PhD in meat science at Iowa State University in 2006. In 2007, Jeff joined the Department of Animal Sciences at UW Madison. 

In this capacity, he provides assistance to meat processors in the areas of product development, problem solving, and regulatory compliance. He also coordinates the meat science workshops and training programs, and he provides involvement and support to youth in meat science related activities. Jeff also conducts research on quality and sensory characteristics of processed meats, non-meat ingredient functionality in meat products, and intervention strategies to control pathogenic bacteria in meat products. But the reason we're all here is because he's going to talk to us about the thrill of the grill, the arts and sciences of making bratwurst and other sausage. And now I have to go and leave and go shopping to get another three or four dozen brats so we can all have plenty afterward. We don't often get to eat the data; tonight we do. [LAUGHTER] Please join me in welcoming Jeff to Wednesday Nite at the Lab. [APPLAUSE] >> Thank you very much, Tom. Good evening, everyone. First of all, I'd like to thank Tom for the invitation to come out and speak at the Wednesday Nite at the Lab. 

This is such a tremendously neat activity, and I'm really honored and excited to be here this evening. This evening's activity or this evening's program, we can kind of call it an activity because there's going to be some participation, some crowd participation involved. And Tom has already mentioned about after the program, but during the program we're actually going to be doing a little product sampling as well. Now, I'm not going to twist arms. I'm not going to require that you participate in the sampling, but if you are a true Wisconsinite, you probably want to heavily consider participating. This evening's topic is The Science and Art of Sausage Making, and I'm going to be speaking specifically about bratwurst and summer sausage. Two products which are so very, very important to this state, have a tremendous amount of history tied to the heritage of this state, and will for many, many years, decades, and hopefully centuries to come maintain being an important thread in the culture and society of this great state. So, the first product that we're going to talk about is summer sausage, and my thought was perhaps we could talk about chemical, physical, sensory, food safety, organoleptic, a variety of different properties of these products. But then after giving this a little more thought, I though perhaps we should talk a little bit about science, a little bit about history, and a little bit about what makes these products so unique. How they're made, how they're utilized and so forth. 

So we're going to carry that format through this evening's program, and the first of the two products that we're going to talk about is summer sausage. Summer sausage is considered one of these two products, dry and semi-dry sausage, and these two categories of products represents one of the oldest forms of meat preservation. If we think about the history, rewind the clock, summer sausage was manufactured for preservation purposes, before times of refrigeration, and in way, a to preserve products. By definition, summer sausage was manufactured in the cooler months, the fall and winter months, so that it could be consumed in the summer during warmer months when foods were more commonly spoiled. A little more about the history of these products, dry and semi-dry sausages and summer sausages, which I've got a couple examples here, are an example of a semi-dry sausage, and I'll explain what the difference is. But these products were developed mainly in Europe, again, as I mentioned, because of the climate. And it hasn't been until the last hundred years or so that we've really started to understand a lot about the science of these products. Around 1900 the microbial basis for fermentation was discovered. Most of these products, as we'll learn, are fermented. Some are acidulated, and we'll talk about what that is. 

Around 1940 the first patent for starter cultures was issued. In 1958 and the early 1950s starter cultures were commercialized. Similar types of starter cultures that are used for cheese as well as other industries. What is so special about this slide is that the first starter cultures that were invented and commercialized were accomplished by a gentleman by the name of Bob Deibel on this campus at the University of Wisconsin. Traditional dry and semi-dry sausages differ from all other types of sausages in that they require microbial fermentation. First and foremost, that microbial fermentation was for preservation purposes. Today, we still utilize it for some preservation purposes. That's why sometimes we can buy these products and not refrigerate them, but more often we apply fermentation, microbial fermentation, for the characteristic flavor as well as the texture. Around the 1900s, before we started really learning about the science of starter cultures and fermentation, the meat industry employed a practice known as back slopping. And, essentially, it was meat inoculation. 

We made a batch of sausage, we had fermentation occurring, it occurred because of the natural micro flora that was on the meat, and we took a portion of that, saved it back, and added it to the next batch. So we were essentially inoculating batch to batch to batch. This gave us many problems in the industry, as you can imagine. Inconsistencies and other types of problems. And so the commercialization of starter cultures used for microbial fermentation was extremely important in the success of the products that we see today. Traditionally, and I'm sure many of you in this audience are very well aware of this and probably can remember the day, but traditionally many dry and semi-dry sausages, even summer sausage, were not cooked. However, due to food safety concerns and the emergence of a variety of some very dangerous pathogenic bacteria, almost all dry and semi-dry sausages are cooked, and that's to destroy those pathogenic bacteria and resolve in safe products. Dry versus semi, and I mentioned this in my very first slide. Just to give you a little bit of a difference or a comparison. So a dry sausage is one that has had bacterial fermentation or acidification, resulting in a pH of 5.3 or less, we'll get into more about that in a bit, and has roughly 25% to 50% of its moisture removed. 

So we start with a hundred pounds of sausage, we result in between 50 and 75 pounds of finished product. We remove moisture, dry that product. Pepperoni, hard salami, Genoa salami, those are examples of dry sausages. Semi-dry sausages, which summer sausage fall into that category, are also fermented either by bacteria or by acids. They also have a pH of 5.3 or less, and they have less moisture removed. Typically, 15% moisture loss. So we start with a hundred pounds of meat, we end up with about 85 pounds of finished summer sausage. So when you go to a grocery store and you look at the price tag, you can kind of make sense of why it may be a little more expensive. You're buying less water, you're buying a more expensive product, a higher concentration and a higher amount of protein. There are standards of identity. 

So when we call a product summer sausage, we must meet specific standards of identity that are established and outlined by the USDA. And for example, for summer sausage and any summer sausage that is shelf stable, that does not require refrigeration, we have to achieve a moisture protein ratio, or MPR, of less than 3.1 to 1. So we analyze this sausage for the amount of protein, we analyze it for the amount of moisture, we divide the two, we set it to one, and that gives us a moisture protein ratio of 3.1 to 1. This is for you guys, for consumers, so that if you're in Wisconsin or California or Massachusetts, if you buy a product that's labeled summer sausage it's going to have the eating qualities, the organoleptic properties that you would expect of a summer sausage here in Wisconsin. And the pH also has to be below 5.0. Now, there are a few different types or styles of summer sausage. There are those that are pH reduced, and that can be accomplished by either fermentation using a lactic acid starter culture or bacterial starter culture, or acidified using an actual organic acid. And there are also products that are non-pH reduced. And we're going to sample a product that is non-pH reduced to give you an idea of how that affects the flavor. There's actually a lot of areas, there's certain regions in the country that prefer non-pH reduced summer sausage over fermented or acidified summer sausage that we would find in Wisconsin. 

As crazy as it may seem, there are people in the US that do not like Wisconsin summer sausage. It's crazy, I know. Not because of the flavor but because of the tang, that sourness which is what fermentation results in. So, many of you might be asking what is exactly in summer sausage? How do you make it? And we're going to walk through those steps real briefly. Tom told me I had three hours. I said no thanks, I'll take one. But if you've ever wondered what's in summer sausage, the very easiest thing to do is pick up the product and read the label because USDA requires that the meat industry puts everything that's in a product on the label. There's a couple nuances to that, and I'll explain that. This is a formulation that we use at the UW meat lab. And we have a state inspected meat processing facility here on campus just a couple blocks down the road. 

We manufacture a variety of different products, one of those being summer sausage of which we're going to be sampling here in a few minutes. But this is a formulation that we use. Exact verbatim out of our recipe. We have 80/20 beef trim which is 80% lean, 20% fat. And these are trimmings that are generated from cutting steaks and roasts and so forth. Sometimes we actually use steaks and roasts if we have to because the sausages are so popular that the meat industry often doesn't generate enough trimmings. Salt. Dextrose. I'll kind of go through here. Black pepper. 

That gives you the heat in the back of you throat. Whole mustard seed, characteristic of summer sausage. More for aesthetic value rather than flavor. Looks nice in a product. Garlic powder, and in Wisconsin we love garlic powder. It's very easy to find garlic summers. Nutmeg. Ground ginger. Sodium erythorbate. Curing salt, which is a combination of sodium nitrite and salt. 

 Lactic acid starter culture. And a little bit of distilled water. We're allowed to add a little bit of water so that we can distribute the ingredients during the mixing. So you can kind of see the breakdown. Very, very simple. Now, when you pick up a product in a grocery store you often don't see a breakdown of all those spices, all those individual spices, and that is one of the nuances of labeling. They can call those spices or flavorings and lump them all together. The reason that that's allowed is because if I gave this out to all the meat plants and I'm trying to sell this product, I would give away my secrets. So it's a way to allow some competition, allow some confidentiality to meat processors' formulations and their recipes. Raw materials that are used, in Wisconsin we eat a lot of all-beef summer sausage. 

Very, very unique to this state. Very few other places in the country is all-beef summer sausage so commonly consumed. But we also use raw materials such as pork, sometimes poultry, elk, bison, ostrich, I've seen mountain lion summer sausage before, and the list goes on and on. It's very common to see combinations of those ingredients. Typically, we target around 15% to 25% fat content in that product. There are some very functional components of those raw materials that we utilize for manufacturing summer sausage. The main portion is the protein portion. And there are three main classifications or three main types of proteins that we utilize for manufacturing sausages and, in this case, summer sausage. One classification are the sarcoplasmic proteins which attribute to about 30%-35% of all the proteins in meat. Those are responsible for the color that you see in meat, whether it's a bright red or maybe brown if it's getting a little bit old. 

That occurs because of oxygen and oxidation of the pigment. Or the cured meat color that we see in summer sausage and ham and bacon and so forth. Myofibrillar proteins which comprise about 50% of the proteins in raw materials. Those proteins are very important for texture, give you the bite and the mouth feel. They're salt soluble so they form gels. When we make sausages, we're actually forming a gel. Stromal proteins are the third classification. Approximately 10% to 15% of the total protein. And stromal protein are typically not a good thing for sausage making because they're high in connective tissue and collagen, and those provide bad eating experiences. Sometimes you get a little bit of gristle in your teeth, that actually is a stromal protein. 

Specifically, myofibrillar proteins are extremely important because those are what give summer sausage the texture that it has. They are salt soluble so that 2.25% salt that we add, referring back to that formulation, that salt solubilizes the proteins. In essence what it's doing, when salt comes in contact with proteins, and in a raw native state proteins are like closed fists, that salt opens those fists up. When that is accomplished there are binding sites which are inside those fists which are then allowed to bind to each other, stick together, and form a gel. If the fists are like this and they are not opened up and the myofibrillar proteins are not solubilized, we basically result in ground beef or hamburger where it's very easy to break apart. So it's very important that we focus and utilize the myofibrillar proteins that exist, which is one of the very, very important functions of salt, there is a variety of others. We focus on myosin and actin. Those are the contractile proteins. So they are the ones that are responsible for muscle contraction. And here is an example of actin and myosin, myosin being the thin filaments with these tails or these heads. 

And, again, when we focus on those it affects the texture. So opening them up, allowing proteins to bind to each other, gives us texture. That can affect water holding capacity. So how much water or moisture the products hold. Again, when we open them up we have binding sites on the inside and, as I mentioned a couple of times, form strong gels. It gives us the finished texture which we all are accustomed to with summer sausage. The freshness of the raw materials used in the manufacture of semi-dry sausages, specifically summer sausages, is absolutely critical in the manufacture of these products because the success of manufacturing summer sausage, the success of fermentation is dependent on the type and the dominance of the micro flora that's on the meat, what bacteria is present. And if we think back from the raw material, so we've got a summer sausage here, we used raw materials generated from trimmings and whole cuts, roasts and so forth, we received those trimmings and whole muscles from carcasses. We received those carcasses from live animals. After animals are harvested, they, essentially, try to degrade. 

They want to decompose and go back to the Earth where they came from. Preservation, fermentation, salt, and cooking is a way of slowing that decomposition down. So when we harvest animals, we have a lot of bacteria present from the environment, from people, from facilities, from tools, and the bacteria that's present after an animal is harvested are typically the enteric forms, the gram-negatives such as E. coli, not necessarily pathogenic E. coli but just generic E. coli, salmonella strains, various coliforms, we also have contamination from humans and environment as I alluded to. Spoilage bacteria, that bacteria that makes milk sour in your refrigerator or vegetables turn ugly colors. Same exact bacteria. The salting and the drying process, so manufacturing dried and salted products favors lactic acid bacteria, staphylococci yeast, over some of those gram-negative ones. So, the preservation of drying part of semi-dry sausages, part of summer sausage, or salting, the addition of salt, is very important to control and change the micro flora that's on the raw materials. That micro flora being inherent and uncontrollable in almost all regards. It is impossible to keep something sterile from the time that that meat leaves the carcass to the time is it put into a product and it ends up on a consumer's table. During the process of fermentation, we have a phenomenon known as microbial flora inversion. 

And this process is extremely important because it shifts the dominance from gram-negative, the coliforms, the E. colis, the salmonellas, to gram-positive bacteria. So it suppresses the  gram-negative bacteria and allows the gram-positives to grow. This is caused by fermentation, and it's really important to understand what level and what type of microbial flora are on the raw materials that we're using to make summer sausage. We can control the micro flora in some regards by adding salt, suppresses the gram-negatives, allows the gram-positives to grow, and by controlling the fermentation. Fermentation happens to be gram-positive bacteria. And we always have to address pathogenic strains because, as I mentioned, most E. colis are gram-negative or are non-pathogenic; however, there are a couple pathogenic varieties. So, this leads into the concept of fermentation which is absolutely critical for giving summer sausage the characteristics that it has. Fermentation, or actually I'll call it acidifying for right now, we'll differentiate between the two. Acidifying is lowering the pH of a meat system. It can be accomplished in two different ways. 

One is through fermentation which uses starter cultures or lactic acid bacteria. The other is by direct addition of organic acids. The purpose or the reason that we ferment, either using starter cultures or acidulants, is to reduce the pH in meat products. So the pH of raw materials of meat is roughly 5.5 to 5.8, and we need to reduce that to 5.0 or less. In doing so, we generate a whole lot of functionality. We have water binding our losses or we can control water binding our losses. We generate flavors. We generate acids or sour notes. We can improve color and we can result in stable color over shelf life of a product. We can improve or increase the shelf life. 

So how long will it last in a grocery store? How long will it last in your refrigerator before it starts getting moldy or slimy or smelly? And it's very important for food safety. The first ingredients or the first way of acidifying is using encapsulated acidulants. I've got a little demonstration here. If I could ask a couple of my assistants to help me with this. The first approach in reducing the pH is using an organic acid. And there are three main types that are used in the meat industry: citric, lactic, or glucono delta lactone. Gentlemen, hold on one moment. The properties of this is that in these capsules it's approximately 75% acid, citric acid, coated with hydrogenated vegetable oil. The mode of action is that after these products are added to a sausage and it's stuffed and we heat treat it or we cook it, the vegetable coating on the outside of these capsules melts and releases the acid. So we receive direct acidification, pH drops instantly. 

I have a couple samples that we'll pass around. A little fun exercise. You don't have to participate if you don't like to, but feel free to do so if you'd like. So we have some encapsulated citric acid that we brought over from the meat lab. If you are interested and you'd like to participate to see how this works, sprinkle a few granules in your hands. Gentlemen, please pass it around. And once you sprinkle a few granules, you only need five or 10 or so, stick it in your mouth and let it sit on your tongue and see if you can taste anything. And then bit through them, and then see if you can taste anything. Again, it's a safe ingredient. We use it for our manufacture in the meat lab, but if you prefer not to participate, that's fine. 

So the reason this is used and the reason that's encapsulated is because if we add acid at the beginning of product manufacturing, we will denature proteins. Acid denatures proteins. Everyone familiar with fresh chorizo? >> Yeah. >> What's a very common characteristic of fresh chorizo? You put it in the pan, you fry it, and what happens? Does it stick together or does it break apart? >> It sticks together. >> Really? [LAUGHTER] Does anybody by chorizo that breaks apart? >> Crumbles. >> Crumbles. Why does it crumble? Have you looked on the ingredient statement? What makes chorizo different than most fresh sausages? What ingredient is different? What's different about it? You usually see acetic acid or vinegar. Vinegar is an acid. It denatures the proteins. Once you fry it, it breaks apart. 

We encapsulate it for summer sausage because we want to control when that acidification, when that denaturation occurs. So the proteins will actually set up. It will start to coagulate and form a gel. Then the vegetable coating will melt. We'll have acid. It won't hurt the proteins. We'll have pH drop. Voila. And we have a product that we'll sample that's been manufactured this way. The way that summer sausage manufactured in Wisconsin is through use of starter cultures. 

And, again, on the labels you will see every product that's been fermented with the lactic acid starter culture. It says it on the labels. They are living bacteria. They're temperature sensitive, so they are what we would refer to as good bugs. They will ferment at certain rates and to a certain extent depending on several factors. One is the meat condition. Are they being out-competed by spoilage bacteria or other micro flora, how much food we give them in the form of sugar, and the cooking conditions. So we can control by fermenting in proper zones or proper temperatures where bacteria like to grow. They like to eat sugar or sweetener and produce acid. And, of course, we can always stop them from growing by increasing the temperature and killing them off. 

Some starter cultures, meat starter cultures, and there are a variety, some starter cultures actually produce more flavor than acid. We rarely see them in summer sausage, but if you're eating a Genoa or a sobrasada or a hard salami sometimes you'll notice some very unique aromatic flavors and aromas. Those are typically from other types of lactic acid bacteria that have the ability to break down proteins and amino acids, break down fats and the fatty acids, and dissimulate carbohydrates. And during that process, which is a long, slow process, you result in some very, very unique, very desirable fermented flavors and aromas. The food effects on fermentation, so we control how the fermentation operates by giving those bugs, the good bugs, food. And the more that we give them, the more they'll eat, the lower the final pH will be. Again, the pH of muscle, raw meat, is 5.5 to 5.8. If we add approximately .37% dextrose, we can result in a pH of around 5.2. The more dextrose, dextrose is a simple sugar very readily consumable by starter cultural bacteria, the more sugar we give them, the lower the pH will go. There's also a time effect for fermentation. 

So I apologize, this doesn't show very well, but on the X axis you have hours of fermentation: 0, 4, 8, 12, 16, and 20. On the Y axis you have pH. Again, we're starting at 6.0 on the very top here. As we ferment, we give it enough time, if there's no food, no dextrose or sugar, which represents the red line, nothing happens. The pH does not change. If we give the good bugs, the lactic acid bacteria, food, the yellow line shows that over time the pH will drop. That is a product of the bacteria eating sugar and out the back end coming lactic acid. So it's consuming, digesting, and breaking down dextrose, a simple carbohydrate, and resulting in acid, lactic acid. The more acid that accumulates, the lower the pH will go. This is important for summer sausage, as well as other dry and semi-dry sausage, because it affects the water holding capacity. 

So the isoelectric point of meat, that's the pH or the point where there are an equal number of negative and positive charges, where proteins actually are tightly squeezed, such as in this picture, the very top picture. Proteins are very, very close together, representing the isoelectric point. As we move closer to the isoelectric point, so, again, pH is around 5.8, so it's around here. The proteins want to hold to water, and meat is 70% to 75% water. So it wants to hold on to that water. As we reduce the pH and we approach the isoelectric point, about 5.2, the proteins want to give up that water. They want to let it go. And that's how we can drive moisture out of semi-dry sausages and we can achieve 15%, 25%, 50% moisture loss. We could not accomplish that without this very, very important scientific principle. And this kind of depicts, as we have different charges, we have more binding, more ability for the water molecules to grab on to those negative charges. 

When we add salt, salt has a chloride ion, negative charge, it actually shifts that whole isoelectric point curve. So instead of the 5.2, which I just explained on the last graph, when we add salt, it shifts it to about 4.9, 4.8. From a manufacturing standpoint, there are a couple different approaches that we use. One is using what is called a silent cutter or a chopper. And this picture depicts what that looks like. It's basically a big bowl, it turns in circles, and it has several very, very sharp knives that chop and dice and cut. An old practice that is almost becoming extinct. Today we typically utilize grinder systems. Here's a typical process flow or manufacturing procedure for summer sausage. We would start with the initial grinder, mix in our ingredients, do a funnel grind, stuff, ferment, and thermal process. 

During the manufacturing, controlling our raw materials is very important. So we use temperature to insure that we do not abuse the fat that's in our sausages. In doing so, we're able to result in the fat particles, the little white pieces that you see, we accomplish that by making sure that the temperature isn't too warm to smear those fats. Mixing time is critical. So some of the science, a little bit of art. We control temperatures throughout the entire process. Mixing is done for a relatively short period of time. We want to solubilize some of those proteins but not too much. We add our different ingredients at different steps in the process. We typically add salt toward the end of the mixing process. 

So the mechanical action helps solubilize proteins. Salt does that as well. We can control how much proteins are solubilized by addressing at what point in time and how much exposure salt has to those proteins. And after we've done all those things, we will run that product through a final grind. Again, the controlling temperatures, grind size are typically one-eighth particle size or three-sixteenths of an inch particle size. And if there's any non-meat ingredients, such as cheese or jalapenos, cranberries or craisins, dried fruits and so forth, those are added at that time. After grinding, mixing and grinding, we stuff the casing or we stuff the sausages. And sausage casings, and I have a variety of these here and I'll leave them up here and you're welcome to come up and look at these, but there are a variety of different sausage casings available for summer sausage and other dry and semi-dry sausages. The most common one is a fibrous casing. This is a mahogany colored fiber. 

Made from tree and plant fibers. Very, very strong. Actually, it's paper that you can tear. If I soak this in water, the fiber is absorbed and becomes very, very, very strong. They come in various colors and sizes. So here's a colored casing. Here's a clear casing. Here's a baseball bat. Or, actually, this is a beer bottle. There's a baseball bat that's a little bit longer. 

Here's a football. Here's cleats. A Wisconsin company makes these. A smaller football with the cleats. A stuffed version of that football with the cleats. You pay for this, of course. A pig with ears. Here's some cloth casings. Here's a little rabbit for Easter. Another little bunny for Easter. 

Perhaps a stocking for Christmas. Another little Easter delicacy. You know, I manufactured some product several years ago in these casings, and it had about 25 or 30 on a smokehouse truck. It was a little scary when I opened up the door and they were all staring back at me. [LAUGHTER] But nonetheless, there are a variety of different types of casings and sizes and so forth. When we cook sausage, so we've got everything stuffed and we're ready to go and cook, we follow a fairly sophisticated cooking process. The first part is fermentation. This can take 12 hours, sometimes shorter, sometimes longer. We utilize dry bulb and wet bulb which the two together give us a relative humidity. And we bring the temperature to a temperature where the bacterial starter culture like to grow, around 100-105 degrees. 

Then, after we have reduced the pH to around 4.6, 4.7, 4.8, we move into the cooking process. The first part is surface preparation. So we have a lot of moisture during fermentation. We want to dry some of that moisture out and prepare the surface for smoke. We then apply smoke. We then cook, continue cooking until we reach a lethality. So we make sure there's no pathogenic bacteria surviving. And then we start the cooling the process. We're actually showering the sausages with water. And the finished product, hopefully, we've resulted in products that have a very uniform appearance. 

Typically, summer sausage needs to have a very desirable, attractive, mahogany external appearance. Should have a very pleasant, cured, smokey aroma, a pleasant flavor of course, and a semi-dry-like texture. That crumbly, slightly rubbery, slightly brittle, slightly mushy texture. What we're going to do now is spend a couple minutes sampling a few different products to kind of reinforce what we've talked about. And, again, you are welcome to participate. If you don't, feel free, you surely don't have to. Seth and Bill are passing around some toothpicks, grab one if you'd like to participate, and some napkins. Instead of plates, we'll just pass out napkins, and then we'll pass out the samples. The first sample that we will pass around is a cervelat, which is this product right here. I purchased it this afternoon. 

Oscar Mayer summer sausage cervelat. Okay, I just lied. This is the product that we're going to sample. [LAUGHTER] A beef cow salami which is very similar to a summer sausage with one main difference. It's not fermented and it's not acidified. So this product should have a very unique flavor. As these samples are being passed around, go ahead, as they're being passed around, grab one. Notice the texture. You'll notice that's it's a little bit moister than you'd typically expect for a summer sausage. I'm sure you all will. 

It has a little bit of water. So it has a different standard of identity, but notice the flavor and see if you can pick up a tang or any acid while you're sampling that product.  Yes? >> Question right here. >> Yes. >> Is there something... [INAUDIBLE]  >> Sure. So the question was, is there any way that you can not use nitrites because of the concern of N-nitrosamines which have been classified as carcinogens, have not been classified as carcinogens in humans but in rat studies they were about 30 years ago or so. The question is, I'll answer that question in a two-fold. Phase one is sort of. You can find some products that are uncured, and the way to distinguished an uncured product is to notice the product would be not pink. 

It would be brown like cooked hamburger or a steak or a roast. The second way that I'll answer that, maybe I'll answer a third way, the second way that I'll answer that is that I would actually highly support the use of nitrites. And as far as that goes, nitrates. Nitrates and nitrites have been an on and off controversy for decades. And they've been centered around the potential formation of N-nitrosamines in rats. Nitrites are in about every vegetable that we consume. They're in our saliva, our bodies actually generate them through L-arginine and some other routes. So you're dietary contribution of nitrites from cured meats or summer sausage is actually very, very low. 95% of the nitrites that you consume do not come from cured meats. They come more from vegetables and the conversion of nitrate from vegetables to nitrites. 

Okay, so the first sample is being passed around. Anyone pick up any acid or fermented flavors? >> No. >> No. Let's pass the second one around as well. So a very bland sausage. The second product that we're going to be passing around is a small diameter. It's an encapsulated product. It's a Hillshire Farms product. This is the only product I could find in the whole city of Madison that did not use lactic acid starter culture. And the reason that I was able accomplish this is because I went to a grocery store in Madison that is not a Wisconsin company. 

It's Hy-Vee which is an Iowa company. But this product does not use an encapsulated citric acid or does not use a lactic acid bacteria. It uses encapsulated citric acid, what we tasted and sampled. Seth, could I join the sampling as well? >> Mm-hmm. >> It seems fair that the presenter should be able to get a sample of summer sausage, I would think. [LAUGHTER] So back to question about N-nitrosamines and so forth. The other aspects of N-nitrosamines is that unless you are heating a product to at least 300 degrees Fahrenheit, you will not form N-nitrosamines. To form them, you must, essentially, pan fry meat products. And the product that's most associated with the concern of N-nitrosamines would be bacon. And there are very strict USDA regulations for how much nitrite is added, it's actually less than other cured meats, and some other ingredients to make sure that there's, essentially, no nitrites left after the manufacturing. 

>> You can't cure without nitrite? >> You can cure without nitrites. Actually, I misspoke. You cannot cure without nitrites. Curing is use of nitrites. Okay, as this product is being passed around, any comments or thoughts? >> Better. >> Better for sure. Anyone pick up a tang or a sourness? >> Yeah. >> Like acid or sour? >> Sour. >> And what I should also note is that this is a beef and pork product. So this is not an all-beef. 

Okay, let's sample the third one which is the meat lab summer sausage which was the formulation that I showed you. All-beef. Salt, dextrose, black pepper, whole mustard seed, garlic powder, nutmeg, ground ginger, and lactic acid starter culture. >> That's good. >> More sour? >> Dryer. It seems a little dryer. >> Dryer. Can I have a sample, please. [LAUGHTER] One would think that the first time I did that it would have resonated to the next.  Definitely a different texture, different manufacturers, different raw materials which add to the great variety of summer sausage that we have. 

Bill. Anyone pick up any different flavors? How about towards the very end? More building in the aftertaste. So the first sample was a cow salami, had nothing in it other than spices and salt and sugar. The second sample had encapsulated citric acid. The third sample had a lactic acid starter culture. Okay, we'll maybe continue, we'll just circulate those samples until they're gone, but we will continue on with bratwurst. And I know that we need to stay on track. So, bratwurst, the other Wisconsin steak staple. So what is bratwurst? What's it all about? The name bratwurst or these products were derived from the old high German language centuries ago. Brat, the first part of bratwurst, means frying. 

Wurst means sausage, of course. We all know what wurst means. We all live in Wisconsin. So when you eat a bratwurst, you are essentially eating a frying sausage. So next time you're at your friends or neighbors say could I get a frying sausage, please. I don't want a bratwurst; I want a frying sausage. Bratwurst, outside the US, is considered a style of preparation. It's the type of a product. In the US, bratwurst is a classification of fresh sausage. So a bratwurst is a frying sausage. 

You don't go to a grocery store and buy a bratwurst in Germany. You buy a type of bratwurst which is a type of frying sausage. And how bratwurst is classified outside the US, specifically in Europe and Germany, is highly regulated. A little bit of some origins on bratwurst, and it kind of depends on where you were or where you're looking at in Germany. There's different regions. And this is just kind of a subset, an example, to give you an idea. So, in the Thuringer region there's a type of bratwurst that were manufactured or invented. In the Franconia region, which is kind of the central region kind of north of Bavaria. And then the Bavarian region, and we've all heard of Bavarian bratwurst, Bavarian style products. And there's dozens of styles or varieties of bratwurst. 

Many of them, if not all of them, are related to a specific town or a region or a recipe, and that's how they are differentiated. So a bratwurst is a frying sausage. A Nuremberg is a bratwurst originating in Nuremberg, Germany. Or Bavarian is in Bavaria, Germany, of course. A couple different styles, a little more discussion on this. So a Thuringer style and the recipes and formulations are just immense. There are so many different permutations. But a Thuringer style typically includes stemless marjoram and it has a lot of herbs and spices. So it's more of an herbier frying sausage, an herbier bratwurst. A Munich style, typically that's a cooked bratwurst, and they're generally white because they're not cured. 

Sometimes in Wisconsin we'll find Weisswurst. And Weisswurst is a type of a Munich sausage, again, invented in the Munich area. Weisswurst typically contains veal. Sometimes it's all veal. Sometimes it's veal and pork which is why it's so white. Typically a finer ground sausage and cooked. And there's a picture of it on the bottom. Has lemon and parsley as characteristic ingredients and is steamed cooked, and the cooking is what gives it that white color. Question? >> I like the summer sausage that's called Thuringer style summer sausage. >> Yep. 

>> Does that have the same idea that it has the spices too? >> Correct. Thuringer style summer sausage in the US typically has more mustard flavoring. And it's typically leaner and it's typically a little bit coarser ground. There can be some variations. Like Thuringer bratwurst should have more marjoram and a few things. And you could find that spice as well in Thuringer style summer sausage. Again, there's a lot of different permutations. Nuremberg style are small diameter from the Franconia region. Again, includes stemless marjoram. And the typical spices are salt, pepper, mace, ginger, all spice, cardamom, lemon juice, or lemon powder. 

And the bottom right picture is a Bavarian bratwurst, and I know it's hard to read it but it says traditional Nuremberg. This product was actually found down the street at Trader Joe's. And you really can't see the picture but it says imported, product of Germany. There are only four sausage companies in Germany that are allowed to make this product and put Nuremberg on the label. There's actually, like, 150, but there are four that can sell and distribute. Four like Oscar Mayers or Johnsonvilles. So that product is imported from Nuremberg, Germany. It is a fantastic product. It's like a small diameter breakfast sausage link. Great, great product on the grill. 

Typically served on a hard roll with the right beverage, not water. [LAUGHTER] It is absolutely to die for. Bavarian style typically has some non-fat dry milk which aids in the creaminess. It gives it a little bit different texture. You sometimes see that in Braunschweiger. Fresh onion, white pepper, nutmeg, and lemon juice are the two spices that should stand out in those products. So, the question then, what's in a bratwurst? A recipe right from the meat lab. Pork trim, 80/20. Water, we can add a little bit water, 3%. So for every hundred pounds of sausage, we can add three pounds of water which is allowed by the USDA. 

It's so that we can mix the ingredients. Salt, of course. Sugar. Black pepper. Sage. Ginger. Coriander. Nutmeg. Cardamom. All very characteristic bratwurst seasonings. 

And you have can different renditions of this, different variations, different amounts of each which all can impact the flavor and aroma of a finished product. And that's where a lot of the art comes in to bratwurst manufacturing. The companies that can find that right balance of those different ingredients, that understand the layers and complexity of spices and how you have synergistic effects from including different ingredients, those are the really, really good products. A lot of bratwurst, especially in Wisconsin, are made using pre-rigor pork meat. And to understand pre-rigor pork meat we have to understand a little bit about muscle biochemistry. And we'll look at the conversion of muscle to meat. When the animal is harvested and the carcass is hot and we've rolled it into a cooler and it starts chilling down, from a biochemical standpoint that carcass goes into rigor mortis, which is known as the stiffening of death. Rigor mortis occurs when ATP is depleted, the energy source, the thick and the thin filaments. The proteins lock such as in that right picture up there. The effect is that it decreases tenderness because you have a lot more protein that you have to chew through. 

It gives you tougher meat, and you also see a pH reduction because of the buildup of lactic acid. If we look at glycolysis in living muscle, we have glucose coming from the blood stream, glycogen coming from the liver used to generate ATP. Goes through the citric acid cycle. Generates CO2 and water and a whole bunch more ATP. Produces a little bit of lactic acid. That's broken down and utilized in the muscle and taken out, taken away. When that animal is no longer alive, no longer with us, at the very beginning of rigor, that pathway changes. Blood stream glucose is still there so it's still being broken down. Glycogen from the liver and what's ever present in the muscle cell is still there. It's still being broken down. 

ATP is still being generated a little bit. But we're then generating a whole bunch of pyruvate and a whole bunch of lactic acid. Lactic acid does not have the ability to be taken away so it builds up. pH of a live animal is around 7.0. pH of meat is around 5.5, 5.8 because of glycolysis and because of the buildup of lactic acid from pyruvate in an anaerobic state. The rate and pH decline, how fast or slow, and the final pH has a tremendous impact on the quality and the water holding capacity of raw materials. So in a perfect world and a perfect situation we want to see a pH, and on the X axis we have hours post-mortem. So zero would be at the time of exsanguination, time of death. pH on this axis. Again, 7.0, pH of living tissue. 

If we see a nice slow pH decline, we consider that normal. If we see variations in that pH decline, it affects meat quality significantly. These pictures are not the greatest and I apologize. On the left is PSE, pale, soft, exudative. Very light colored pork. Very watery pork. Very tough and dry pork. It follows the red line, a very rapid pH decline. A lot of acid, lactic acid, is produced very quickly. Acid does what to protein? Denatures. 

Destroys the functionality. If we go to the other extreme, we go to this line which is the white line, we see very limited pH decline. The meat looks like this which is know as dark, firm, and dry. A high ultimate pH. High pH, a lot of negative charges. A lot of negative charges, a lot of water binding. That water is being held very, very, very tightly. When the light reflects when you look at that piece of meat, the light is being absorbed. It's like wearing a black shirt. That's what makes that meat very, very dark. 

From the PSE standpoint, a lot of water on the surface because the proteins are, essentially, squeezing the moisture out, light is refracting. It's like wearing a white shirt. So, why is it important? It is what pre-rigor processing is based upon. So, immediately after harvest, now we're talking pork carcasses, within minutes, while the carcass is still hot, 104-105 degrees, we bone the carcass out. We remove the lean and the fat. While it's still hot we run it through a grinder. Then we transfer that meat to a mixer. We add salt and some type of chilling medium, typically CO2, dry ice can be utilized, but something that has a lot of chilling capacity, and we reduce the temperature of that meat within a very short period of time. Ninety minutes, oftentimes faster than that, to a temperature where glycolysis slows and in essence stops. Question, sir? >> [INAUDIBLE] >> CO2 does not provide any acidification. 

CO2 produces carbon dioxide and it dissipates carbonic acid, but no, not the amount that we're utilizing. Yep. Very good question. After that product is chilled, so we've stopped glycolysis and we've stopped the build up of lactic acid, we then add our ingredients, we do a final grind, and in the meat industry we use a lot of bone collection systems to make sure there's not cartilage or hard bones that could end up in the finished product. We stuff that product. Typically in Wisconsin we use a lot of natural casings such as this. We also utilize some collagen casings which are generated from the collagen from the skin layer or the flesh of beef hides. This whole process from the time when the animal is stunned to the time that that sausage is made, the time that we get to this point, is typically less than 45 minutes. Very, very, very, very fast. And we go from a temperature of around 102.5, live animal temperature of hogs, swine, to less than 40 degrees. 

This is what results. On the left we have post-rigor pork, pork that was not done using the pre-rigor process. So it was allowed to go through glycolysis, acid was produced, some protein nitration occurred because it's inherent, it's inevitable. On the right side is a picture of raw materials that were generated from pre-rigor trimmings. Much redder, much darker, higher pH, higher water holding capacity. Here's an example of a fresh sausage made using post-rigor trim. So normal trimmings that have gone through rigor, been chilled normally. And, again, these pictures aren't that great. Can you guys tell some differences? Hopefully you can. The picture of a post-rigor bratwurst. 

Much darker red. >> Pre-rigor. >> Pre-rigor. Thank you. It's getting late in the night and I'm getting hungry for a bratwurst, you know? [LAUGHTER] Another side by side picture of regular, post-trim or post-rigor, and on the right a pre-rigor. And I've got some examples of some products. A post-rigor versus a pre-rigor. We've all see these products in grocery stores. Now you know exactly how those products were made and why they're different. So I'll just pass those around. 

>> Is that part of the labeling? >> It is not part of the labeling because there is no chemical change, it's not a process which changes the muscle, fat, any compositional components. So the final product then is a product that has great consumer appeal, bright cherry red meat is very desirable, of course. Improved water holding capacity because we have a very high pH and those proteins are holding on to a lot moisture because there's a lot of negative charges in those muscle cells, in those tissues, and it should result in overall higher quality, a very enjoyable eating experience. I thank you very much for your time. It's been an absolute pleasure visiting with you this evening. Are there any questions? [APPLAUSE]