The Science Of Making Great Beer How do yeast, water, hops and grain combine to form a lager, pilsener or ale? The process requires careful supervision and tightly controlled conditions. Expert brewmasters explain how temperature, timing and ingredients all factor into making an excellent beer.
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The Science Of Making Great Beer

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The Science Of Making Great Beer

The Science Of Making Great Beer

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This is Talk of the Nation: Science Friday. I'm Ira Flatow. When you think of Wisconsin, a few things do come to mind. There's the cheese, the Green Bay Packers, the Milwaukee Brewers, and of course, beer. From Schlitz, the beer that made Milwaukee famous as the jingle goes, to Shotz, the fictional beer on the Laverne and Shirley Show, beer brewing is synonymous with this city. So, what better place to learn about the science behind this age-old craft and what better time? Did you know it is the American Craft Beer Week, after all? So, this hour, we're celebrating. We've gathered up the region's best brewmasters. Those are large and small brewers to teach us about the chemistry that turns grain, hops, yeast and water into the lagers and ales and porters and stouts. We're also going to talk about why - what is it about Wisconsin's unique cultural heritage and natural resources that made this area a center for brewing? What's going on around here?

Maybe you folks in the audience here at the Public Museum can tell us about this area. I'll ask you, our number 1-800-989-8255 and if you're here at the Milwaukee Public Museum, you can step up to the microphone and ask your questions. I invite you to do that. Also, if you're in Second Life, you can go over to Science Friday Island and go to the folks with the Science Friday t-shirts. Maybe get one for yourself if you like one over there, for your avatar, and ask questions that way, too. Let me introduce my guests, Russ Klisch is the president and founder of Lakefront Brewery here in Milwaukee. Thank you for being with us.

Mr. RUSS KLISCH (President and Founder of Lakefront Brewery, Milwaukee): Thank you for having me.

FLATOW: Thank you for the tour that you gave us.

Mr. KLISCH: Sure.

FLATOW: Of the brewery. Lyn Kruger is president and chief operating officer of the Siebel Institute of Technology in Chicago where she teaches brewing and beer tasting. Correct?

Ms. LYN KRUGER (President and Chief Operating Officer of Siebel Institute of Technology, Chicago): That's correct.

FLATOW: Wow. We're going to find out more about that.

Ms. KRUGER: Fun job.

(Soundbite of laughter)

FLATOW: I bet it is. Must be a line waiting to get in for that?

Ms. KRUGER: There is.

(Soundbite of laughter)

FLATOW: Kirby Nelson is the brewmaster for Capital Brewery in Middletown, Wisconsin. Thank you for being with us today.

Mr. KIRBY NELSON (Brewmaster, Capital Brewery, Middletown, Wisconsin): Oh, this should be a hoot.

(Soundbite of laughter)

FLATOW: If you're here, maybe it will be. David Ryder is vice president of brewing and research and quality assurance at the Miller Brewing Company in Milwaukee. Dr. Ryder is a yeast specialist. Is that correct?

Dr. DAVID RYDER (Vice President of Brewing and Research and Quality Assurance, Miller Brewing Company, Milwaukee): Well, it's all about happy yeast and fermentation and that's why we make the beers that make thirst worthwhile.

FLATOW: Let's talk about that. Let's begin then with yeast. What role does yeast play in making beer?

Dr. RYDER: Well, the interesting thing about yeast is that - of course we all think about, you know, while we're making beer, that we're just making a moderate amount of alcohol and CO2. But in fact, we're making thousands of flavor compounds. Some of those flavors come from the malted barley. Some of them come from the hops. But many of them come from the yeast or are transformed by the yeast, and there's millions of yeast cells that produce every little drop of beer. So, it's extremely important to have the yeast happy.

FLATOW: How do you keep them happy?

Dr. RYDER: Well...

FLATOW: Vacation? I mean...

(Soundbite of laughter)

Dr. RYDER: You've got to talk to them. Sometimes you play music. We play music to our yeast at Miller Brewing Company...

(Soundbite of laughter)

Dr. RYDER: And that's very important and then...

FLATOW: Classical or rock?

Dr. RYDER: It's rock. Rock mostly, yeah. You know, they like Led Zeppelin. Classical doesn't go down so well with them, but Led Zeppelin does.

(Soundbite of laughter)

FLATOW: Kirby Nelson, let's talk about what happens in the whole brewing process. Take us through a simple brewing process. How do you get those yeast to be...

Mr. NELSON: You know, quite frankly when people come in and say, what do you do for a living? I have to be honest. I don't do anything. My wife will be the first to attest.

(Soundbite of laughter)

Mr. NELSON: But I look at myself as environmental technician - you know, brewing has been around for thousands of years and what we've learned over this time is that Mother Nature's a wonderful thing. And if we take these raw materials that Mother Nature gives us and put them in a very specific environment that they have to behave in a certain way. They're never going to let you down. And that's quite frankly what we do. We take this for the most part, malted barley and malting is a process where the barley is wetted, allowed to germinate to a certain point. Then that growth is arrested by the use of heat, which activates all sorts of biochemical systems in the barley and make it a lot more suitable for what we want to accomplish in a brewing process and it makes it taste a lot better.

FLATOW: And then, what do you do? What happens? What's this process?

Mr. NELSON: We take this barley and basically ground it up, mix it with water, make an infusion of mash, a porridge per se. Hit a series of temperature steps to break down complex substances, taking advantage of enzymes that are actually present in the barley to cause breakdowns of complex things such as starch into simpler forms. And in the case of starch, simpler sugars that the yeast could eat. When you see the kettles associated with a brew house, we don't make beer in that particular - those vessels, we make a fermentable liquid called wort. And then we cool this wort, oxygenate it and it's over to Dr. Ryder's department.

(Soundbite of laughter)

FLATOW: Lyn Kruger, can you look for a yeast that gives you a specific flavor? I mean, can you be that picky about the yeast?

Ms. KRUGER: Oh, yes, you can. I think it depends very much on the style of beer that you're making. So, depending on the flavor components you want in the ultimate beer, you choose a yeast accordingly and there are hundreds and hundreds of different varieties of yeast that you can choose from to give you the flavor you want.

FLATOW: What makes a different - Russ, what makes for a different kind of beer like you know, the lager or ale or porter or something like that?

Mr. KLISCH: The difference between a ale and a lager would be the yeast. So, there's two different styles of yeast to...

FLATOW: The four of you have all said yeast in this. That is the...

Mr. KLISCH: Yeah. But they also have specialty grains a lot of times that go on in - to make a darker beer, use roasted grains, or some caramelized grains will give you an amber-colored beer.

FLATOW: What does the hops do? We've seen now the commercials are all showing, it's hops. People - there's one where the brewmaster's rubbing it between his hands and smelling his hands for the hops. What do the hops do? Any of you want to...

Mr. NELSON: Yeah, well I can - perhaps I can start on that.

FLATOW: Go ahead.

Mr. NELSON: There are five things which actually hops do generally. First, they were first used because of their antimicrobial properties, stopping nasty things from actually growing in beer. Beer is actually safer than water. You know, water can harbor nasty microorganisms such as salmonella or shigella or even cryptosporidium. But beer never does that because, partly because of the hops. So, the antimicrobial properties are very good. Then it has flavor, mouth feel, sort of bitterness and also aroma. So, hops are very, very important to the overall, you know, makeup and the flavor of the beer.

FLATOW: Do you have a trade secret? Over there at Miller are there trade secrets?

Mr. NELSON: Oh, we have lots of trade secrets. In fact I'm sure that all of us have our various sort of trade secrets...

FLATOW: Do you all have sort of trade secrets that you've discovered that other people might not know about?

Dr. RYDER: I can't tell you that.

(Soundbite of laughter)

FLATOW: The other end to that is that or I'd have to shoot you. Is the other - Lyn? Do you have any comment on that. I mean, it sounds like to me, it's sort of an art more than a science here because every knows how to do the simple science part of it.

Ms. KRUGER: I think it's a combination. I think also, when you get to larger breweries like Miller, there may be more trade secrets than when you get to the craft industry where they tend to share information a lot more readily and in fact, share raw materials, they'll, you know, trade malts. They'll trade hops. So, there're less trade secrets. I think in the craft industry than there is in big commercial brewing.

FLATOW: Yeah. Russ, do you agree with that?

Mr. KLISCH: Yeah. We probably have trade secrets we don't know about.

(Soundbite of laughter)

Mr. KLISCH: There's a lot of times, you have what they call house flavor in beer. And we just - from your equipment which you use or the technique. You might even not know what you're having, but a lot of times you can brew the same recipe in two different breweries and end up with two different beers.

FLATOW: Lyn, tell us about tasting. Do you have to teach someone how to be a beer taster?

Ms. KRUGER: Yes, you do. We have, as part of Siebel Institute, we have laboratory services that we offer and one of the services is a taste panel. So, breweries will send their beers in to us and we'll do a taste panel evaluation. And you do need to train people to recognize the various different positive, negative attributes in beer to be able to describe them.

FLATOW: Mm hmm.

Ms. KRUGER: So, yeah, there is training and we do the training as well at Siebel. We do a lot of sensory training for brewers, for lots of different people.

FLATOW: How is the price of grain now, which is skyrocketing, is that affecting the price of beer, too, Kirby?

Mr. NELSON: Oh, quite a bit. I know of the price of - the price that we pay for our base malt has more than doubled in the last year, and especially malts - especially the ones that we utilize from overseas, have gone up almost 300 percent. It's, quite frankly, very scary.

FLATOW: But people will continue to buy beer, pretty...

Mr. NELSON: Well, if they have their priorities set correct...

(Soundbite of laughter)

Mr. NELSON: No doubt about that. I think if I could touch on something, somebody made a very good point. A lot of folks asking, what is beer, an art and a science, so understand, beer making has been around thousands and thousands of years. The oldest known recipe for a foodstuff ever found is a 7,000-year-old recipe from ancient Mesopotamia for beer.

So back then, we didn't understand science like we understand it today, but as time, you know, went on, we became a little more educated, let's say, as a species, and in terms of beer making, sure it's an art. You have to develop a feel for how to put these, you know, raw materials together, but as you learn more about the science, the biochemistry, the specifics behind it, it can help you in your art, and help you know how to modify the situation you're dealing in, and try to make a better glass of beer.

FLATOW: What's the difference between beer and malt liquor?

Mr. NELSON: That's a governmental designation from the United States, where at one time any beer that was more than five, or five and a half percent alcohol by weight, it was called, it was called malt liquor, and that kind of morphed into today what's considered a relatively inexpensive beer with a lot of syrups in it that give a lot of alcohol kick per se, but not a whole lot of malted barley flavor, and the alcohol can vary quite a bit.

FLATOW: And some of these new drinks in bottles, these hard sort of drinks, people think they're actually drinking alcohol, when they're drinking malt liquor, right, hard alcohol when they're drinking malt liquor. Is that correct, David?

Dr. RYDER: Well, so, you know, malt liquor is really, as Kirby said, it's just designation of beer, and it's just slightly higher in alcohol content than, you know, say, your normal beer, such as, say Miller Lite, Coors Light, Bud Light, which are about 4.2 percent alcohol by volume.

FLATOW: What create - what is a light beer? Why is it called light? What makes it different than the other beers?

Dr. RYDER: Well, in...

FLATOW: Is it just calories in the beer?

Dr. RYDER: Well, in this country, and I have to specify, it's this country, it's calories and carbohydrates, so you're low in calories, and you're low in carbohydrates, but in other countries, such as Australia, such as the U.K., where I originate from, it can mean lower in alcohol, but here in the States, we don't do very low alcohol beers.

FLATOW: Lyn, as someone who tastes light beer, is there real difference in taste between them?

Ms. KRUGER: Between different brands of light beer, or between light beer and regular beer?

FLATOW: Take your choice.

Ms. KRUGER: OK, I think, depending on which light beers. Light beers generally tend to taste fairly similar. I would think there are some that are different, and they certainly taste quite different from a regular beer. For example, if you talk about, you know, Bud and Bud Light, or Miller and Miller Lite, there is a difference in the body, the mouth feel, and in this case, the alcohol concentration is slightly different as well.

FLATOW: Is it worth the difference in the calories? The difference in taste? Do you think the taste...

Ms. KRUGER: I - it's personal preference, I think. You know, I don't think the calories make that much difference. I always say, you know, liquid calories don't count. It's just what you eat that counts, so it really doesn't matter.

(Soundbite of laughter)

FLATOW: I think that's a good, good place to take a break that we have to take. Everybody contemplates that. We're going to come back, and talk lots more about the science of beer and the culture of beer with Russ Klisch, Lyn Kruger, Kirby Nelson, and David Ryder. Our number, 1-800-989-8255. We're also in Second Life on Science Friday Island. Fly right over to that spot, you can ask us some questions, so stay with us. Be right back from Milwaukee. I'm Ira Flatow.

(Soundbite of music)

FLATOW: This is Talk of the Nation: Science Friday from NPR News.

(Soundbite of music)

FLATOW: You're listening to Talk of the Nation: Science Friday. I'm Ira Flatow. We're talking this hour from Milwaukee, about beer with my guests, Russ Klisch, president and founder of Lakefront Brewery here in Milwaukee, Lyn Kruger, president and chief operating officer of Siebel Institute of Technology in Chicago, Kirby Nelson is the brew master for Capital Brewery in Middleton, Wisconsin, David Ryder, vice president of the brewing, and research, and quality assurance at the Miller Brewing Company.

Our number, 1-800-989-8255. In our audience, we have someone, who is also a beer expert. He knows a little bit about what made Wisconsin the center for beer brewing. Robin Shepard is interim vice chancellor for the University of Wisconsin Extension, and associate professor of life science communications, and the author of Wisconsin's Best Breweries and Brewpubs. I think it's a bestseller in this audience. Thank you, thank you for being with us today, Mr. Shepard.

Professor ROBIN SHEPARD (Interim Vice Chancellor, University of Wisconsin Extension): My pleasure, thank you.

FLATOW: Let me ask you this question about Wisconsin, and maybe Milwaukee. You've written a guide to the local breweries. How did you get started in this venture? Was this something you just wanted to go around sampling, or was it an academic?

Professor SHEPARD: Well, it does definitely start with, where can I get a good beer and a good meal to go with it, and - but, I'm probably like a lot of folks, maybe a few in the audience where, you know, you begin to get fascinated by what your panel does in the way of the products they make, and I can remember standing in a small little brewpub, and actually on - looking out over, sort of, the Green Bay area, one evening late at night, and it was just me and a work colleague there, and lo and behold, the person on - across in that bar, was the owner of the little brewpub, and he started talking to us about the different styles, and the different flavors, and I was probably hooked from that point on.

Professor SHEPARD: It went from there to, like what a lot of beer enthusiasts do, you know, you squirrel away a coaster from time to time, you take a menu home, after the great dinner, you know, and next thing, you know, in my house, I had a couple of file cabinets, filled with beer memorabilia.

FLATOW: Wow! So, you seem to have sample thousands of beers then. I'd hate to have to put a number on it, Ira.

FLATOW: So, have you, in all that time, have you found a favorite?

Professor SHEPARD: Well, you know, I got to admit, wherever I'm at, probably is the answer of the day, but in reality, no, I hope I don't find that favorite one, because I love the journey, that pursuit of good beer, good food, the culture of what you see along the way, and particularly, the brew masters. In another life, I was a broadcast news reporter, and I learned very quickly that everybody has a fascinating story, and in the brewing industry, some of those stories are indeed very fascinating.

FLATOW: Uh-huh. So, what is fascinating then about this area, about Wisconsin, that made it the beer capital?

Professor SHEPARD: Well, you don't have to go too far. The Great Lakes were one big reason. It was really almost a clash of both the culture and the natural resource base, is what made us a beer state, and in particular, Milwaukee. If you think about the Great Lakes for water, for ice, for storage, some of these - the older breweries, that have been here, have actually restored their caves where they would have stored ice and beer to lager, before the mechanical refrigeration came on line.

We also, in Wisconsin, folks may not realize it, but we have a strong forestry industry, and you need - you have companion development that happens with a brewery, the cooperage industry, those people who made barrels. We had a lot of forest in the state, in fact, to this day. We're over 45 percent forested in Wisconsin. Then you couple that with our heritage of who came here.

In 1850, our state population was somewhere around 300,000. Of that, about a third of that population base were foreign born, and of that number, about half were Irish, and then there was a big German contingent. All of that, that European heritage, where beer was part of who they were, they brought with it. If you look at some of the early manifests of the brewers themselves that made Pabst and Miller, and some of the small town breweries, they listed brewer on their manifest when they immigrated to this country.

So, the culture, combined with the natural resources, we also were a state that could produce a lot of barley in the 1800s, and we were once the leading state for the production of hops, prior to Prohibition.

FLATOW: 1-800-989-8255. Hang on - hang out there for a question or two more. Let's go to Patrick in Freeport, Illinois. Hey, Patrick.

PATRICK (Caller): Hi, how are you? Love the show today.

FLATOW: Thank you.

PATRICK: I had a question for the panel, and I would also like to address Kirby directly. I've been to your brewery in Middleton at least once, and I have a six-pack of your Special Pilsner in my fridge right now.

(Soundbite of laughter)

PATRICK: And my question for the panel is, I am an avid home brewer, considering a career change, and I was just wondering if I wanted to get into professional brewing, how am I to go about that?

FLATOW: How do you turn a hobby into a business is what you're asking, right?

PATRICK: Precisely.

Ms. KRUGER: All right, well, I can, maybe, start off. We are, in fact, a brewing school, and one thing that you can do is get a, you know, formal brewing education. We have, probably half our diploma class this year were home brewers looking to change profession, to become professional brewers, so we offer a lot of different programs and courses from introductory to, you know, to diploma level, to actually give you the training and education you would need to make that transition at Siebel Institute.

FLATOW: You have to be in Chicago? Do you have online courses?

Ms. KRUGER: We do have online courses. We have one online course. It would be the equivalent of a two-week campus course. It's kind of an intermediate course. Our primary diploma course, in fact, half of the time is spent in Chicago, and then we fly students over to Europe, and they spend the last five weeks in Munich and traveling around Europe, so it's quite international.

FLATOW: There you go, Patrick. That's your first step.

PATRICK: I see. Thank you very much.

FLATOW: Thanks for calling.


FLATOW: 1-800-989-8255. Russ, I understand that you make organic beer.

Mr. KLISCH: Yes.

FLATOW: Is that more challenging to do than - what's the difference? We see organic on the labels of everything now. Why shouldn't beer all be organic?

Mr. KLISCH: Yeah. Well, at one time, it was all organic, way back when the United - when Wisconsin first started brewing beer, we - all the beer made here was organic, because it was made without any heavy fertilizers, or pesticides on it, and in 1996, we became the first brewery in the country to make an organic beer under our own label, and so, it's a little bit challenging with it.

You use - the grain is a little bit smaller in size. You have to crush it a little bit differently. The hops - there's not as quite of a wide variety of hops; when you style a type of beer, you want to make sure the style is matching with the style of hops.

FLATOW: So, anybody, basically at home, is making organic beer?

Mr. KLISCH: If they buy organic grain or organic hops.

FLATOW: It's easy to - can you buy that stuff online?

Mr. KLISCH: Yes, there are organic home brew supply stores out there.

FLATOW: Yes, all right, let's go to the audience. Yes, sir.

DALE (Audience Member): My name is Dale Bessler (ph). I'm a science teacher down here for an outing. Unfortunately, this might be a little tricky to bring back to the classroom.

(Soundbite of laughter)

DALE: So, I'll ask a different question. My question is, I understand there's a hops shortage, and could you tell us a little bit about that? And, how it'll affect my evening?

(Soundbite of laughter)

FLATOW: May have to go to a movie.

(Soundbite of laughter)

Mr. NELSON: Yeah, it was a - it's almost a unprecedented time for us in the industry in terms of, we're getting hit, just besides fuel cost, you know, going through the roof, also on grain cost and hop. For many, many years, there was a glut of alpha acid; the bittering compound that we achieve out of hops is called alpha acids, and this can be cut in - put in an extract form that'll keep for quite a while, and from what I understand, there was a lot of extract in the market for a long time. Combine that with hop farmers getting beaten up very badly for price. We went from well over 200 hop growers in this country in the '80s down to 45, and in the last year, we had, I would say a biblical-type set of events happening. There was a - one of the hop companies in this country had a huge warehouse fire that destroyed four percent of the alpha acid, I believe, that was available in this country, perhaps the world.

The British hop crop was in tough shape, in the steering region that grows a lot of hops in the weekend, two out of three days, got destroyed by hail all over the place. There were issues, and all of a sudden, we went from hops being, for example, the classic American hop Cascade, I was paying three-thirty a pound for this, a couple of years ago.

This June, if folks can get it off of, you know, market, in that contract, it's going to be up to 50 dollars a pound. And it was a combination of many things, and let's say, well, let's just plant more hops. Ironically, I believe it takes three years for a hop field to get into full production, so there's a turnaround time here, and it is going to flatten out as we've been contracting for hops. I've noticed that they're asking us to contract out for quite a few varieties five years out, and the price is dropping on an annual basis, so I believe, the hop shortage is a short-term thing.

FLATOW: David Ryder, did you want to say something?

Mr. RYDER: No, you know, I think that the American hops, we use 100 percent American hops at Miller, and I think the hop varieties here in the states, states of Washington, Oregon, and Idaho right now, are, you know, absolutely superb hops, but you know, Kirby is right. He gave you the history, and the prices are very, very high right now.

In fact, for some varieties, some, you know, very specific varieties, you can pay up to about 500 dollars a pound, because they're so scarce.

FLATOW: How do you make - you make an awful lot of beer every year, right? And would that be - how do you keep it so consistent to stay exactly, to taste the same, with all those batches that you make?

Mr. RYDER: Well, I think as the whole panel will actually tell you, you know, the, right the first time, if you're going to make say, the Miller Lite, which is a single wort stream, and to make it right the first time is actually very difficult because you're doing it batch after batch, you know, you're doing it brewery after brewery. In our case, we've got six major breweries across the country. So it's not an easy thing to do. But with the right procedures and the right quality, and all the panel are very experienced in those things, then you can certainly do it.

FLATOW: Question here from the audience. Step up to the mike. Go ahead.

ABBY (Audience Member): Hi. I'm Abby Rosen (ph). I actually get to take this back to my classroom because I'm a biochemistry professor at Marion University in Fondulac. This past semester, we made cheese and beer and wine.

FLATOW: All together?

(Soundbite of laughter)

Ms. ROSEN: Separate weeks. If I were to actually inspire my bachelor chemists or my bachelor biologists, do you guys have jobs for them, or what kind of background would you like them to have to come work for you guys?


Ms. KRUGER: Well, we personally wouldn't because we're a school that prepares people. But certainly for the students that leave, for our alumni, we have a job posting and a system where we help, you know, put them in touch with people who are looking to employ. And we haven't had an alumni yet that hasn't found a job. So that's probably...

FLATOW: What's the most important trait that a good alumnus should have? What makes a great - Kirby, what makes a good person that you're looking to hire in the beer industry?

Mr. NELSON: A very intense, solid work ethic. Understand folks, everyone would think, wow, how cool. You're making beer for a living. And you know what? Yeah, it is. But understand. Brewing, from my standpoint, is 90 percent drudge work. You are in there cleaning, sanitizing. You want just one little microorganism, that yeast you choose to work on, the wort that we're making to create beer. Keyword, micro, very small. Have to sanitize, understand what needs to be, to keep that environment very clean. In answer to a question, biochemistry is a wonderful, I think, entry into the field of brewing, and having a good understanding or how things happen like that and microbiology.

FLATOW: Is there a holy grail of beer that hasn't been achieved yet? Something that you'd like to make, and you would like to figure out, have a certain consistency and - Russ, you're sort of laughing at me here, like, what is he talking about?

Mr. KLISCH: That's like saying all the music's been invented. There's always something out there you can take and right about now, there's a lot of different styles of beers being made without the four major ingredients.

FLATOW: But do you have to craft it for a new generation of drinkers? I mean the kids who are going to be the new beer drinkers, do they have to have something different that their grandparents didn't have, or some sort of attraction to the drink?

Mr. KLISCH: Well, you're always looking for a new ingredient or something that gives it a little different style or type to it. But you know, beer's been around for 600 years or so. And it's been a pretty successful beverage in most periods of time. So I think it's not going to change too much. But you're always looking at something from some aspect.

Mr. RYDER: Yes, I think perhaps I could answer that, and we've actually forgotten the kinds of beer styles that used to be in existence. There are hundreds, thousands of beer styles that used to be made, and that are just not made anymore. And I think it's a challenge to all of us to sometimes go back in time, and to look at some of those older beer styles. And could I just, could make a comment to the question that was asked earlier about sort of education in brewing. I'm a biochemist, and a bit of a microbiologist, and so on. We always have places for biochemists and chemists and microbiologists.

FLATOW: Talking about beer this hour in Talk of the Nation's Science Friday from NPR News. Let's see if we could go to the phones to Doug in Grand Rapids. Hi Doug.

DOUG (Caller): Hi there. Thanks for taking my call.

FLATOW: Hi. Go ahead.

DOUG: I have a question. I'm a big Stroh's drinker. I have been from back in the day when they were in Detroit, Michigan. And they always made a point to mention their so-called unique fire-brewing process. And I just wonder, I don't know if it's made that way anymore, now that Miller's making it. But I wonder, is all beer made, you know, using heat, and if not, what are the advantages and disadvantages of using heat or not using heat?

FLATOW: Did they ever tell you, Doug, what fire brewing meant?

DOUG: Well, they, I know they had, you know, that you would see - I never made it to the brewery before they tore it down unfortunately. But you know, they would - you could drive by and see these big copper kettles right in the window. And apparently, the beer was brewed, you know, was actually heated during the brewing process.

FLATOW: Let me see if I can get an answer. Anybody know what fire brewing is?

Mr. RYDER: Yes. First of all, in the preparation of wort, which Kirby was explaining earlier, you have to use heat. You use heat in the mash tun, you use heat in the lauter tun, in the kettle and so on. And so heat is always used. But as the fire brewing for Stroh refers to the kind of heat that was used. You have these gigantic flames underneath these particular vessels that were being heated up, where the wort was boiled. And that was what was called, sort of, fire brewing. You can use steam coils. You can use other types of heat. But Stroh particularly used fire brewing with these gigantic flames.

Mr. NELSON: If I may jump in real quick, that type of heat has a huge difference on the beer.

FLATOW: Is that right?

Mr. NELSON: Oh, when you're using a flame, it's much hotter per se, as it's hitting the vessel. And you're going to get a little bit more caramelization of some of the sugars. For example, we were on contract brewing, making beer for another brewery as they were undergoing growing pains. And they had a flame-heated kettle. We have steam. We had to compensate for us using steam than using fire by adding some caramel malt to the recipe to compensate for this different type of heat.

FLATOW: So you can just change the flavor by changing the kind of heating that you're putting into it? It almost seems like it's more difficult to make beer or you can make it more - in different ways than making wine.

Mr. NELSON: Beer is much more sophisticated. Trust me.

(Soundbite of laughter)

FLATOW: You're going to tell me we have to lie the can on the side now when we store it? Or is that the...

Mr. NELSON: Well, cans are such good packages actually. You don't have to go through any nonsense. You can just put them wherever you want. It's a wonderful way to package beer, by the way.

FLATOW: Is there a great difference in getting beer out of the draft, than it is in the can or bottle?

Mr. NELSON: Certainly can be. You want to hit that one, Dave?

FLATOW: Or is that just mythology? Is it, is brewing so different now than when they made it in big batches and you couldn't get it out of a can or bottle, that it made a big difference? Has refrigeration changed all of that?

Dr. RYDER: Well, beer styles have changed you know, even in the past hundred years. But to be more specific, draft beer, beer out of the keg is next to the freshest beer if you like. You know, once a beer is put into bottles or cans, it starts to age. And aging, unlike wine, is not good for beers. So you need to drink beer as fresh as you possibly can. And I think all of us would agree there. So it's important to be able to challenge your palate by getting to the beer as quickly as possible.

FLATOW: All right. We're going to come back and talk lots more about beer, take your questions. Our number, 1-800-989-8255. We'll talk about some of these other things we hear on advertising about beers, you know. What does cold filtered mean? And does that matter? Stuff like that. So stay with us. We'll be right back after the short break.

(Soundbite of music)

FLATOW: This is Talk of the Nation's Science Friday. I'm Ira Flatow.

(Soundbite of machines from a brewery)

FLATOW: If you have trouble recognizing those sounds, they're from the beer-making process, the bubbling of the CO2 gas coming off the fermentation process and some bottling sounds from our tour from the Lakefront Brewery here in Wisconsin. And we'll be putting together a little video of that tour, Flora Lichtman will be putting that together and you'll be able to see that on our website. We're talking this hour about the art and science of brewing beer, with my guests, Russ Klisch, who's president and founder of Lakefront Brewery, Lyn Kruger, president and Chief Operation Officer of the Siebel Institute of Technology in Chicago, Kirby Nelson, brew master for Capital Brewing in Middletown, Wisconsin, and David Ryder, vice president of brewing, research and quality assurance at the Miller Brewing Company in Milwaukee. Our number, 1-800-989-8255. Let's go to the question right here in the audience.

BOB (Audience Member): Hi. I'm Bob Olsen (ph). I have a question about a style of beer. My favorite beer is called I think a cream beer. It's a very smooth beer. My mother calls it a dessert beer. And I'm thinking of Boddington's in Britain or Wexford in Ireland. The question I have is those two come with a widget inside, a pressurized widget.

FLATOW: Is that the technical phrase for it?

BOB: I actually think it is. I'm not sure. But the question I have is, is it the style of beer that makes it so I don't know, smooth, or is it this pressurization?

FLATOW: Doesn't Guinness come with a widget in the can?

Ms. KRUGER: Yes, it does. It does, and yeah. Cream beers or cream ales, as they're sometimes called are often served with nitrogen as the gas, instead of carbon dioxide. And that little widget is really putting nitrogen into the beer, rather than carbon dioxide. And nitrogen bubbles tend to be smoother. So like Guinness has that very tight foam, and Dave is a foam expert, but so it gives a completely different mouth feel and body to the beer. Carbonation has a trigeminal sensation so it's a tactile like you feel.

FLATOW: Who ever heard these terms describing beer before? Wow, trigeminal, and wow.

Ms. KRUGER: I know, they - but it's your sense of touch basically.

FLATOW: It just shows us how really seriously you take your beer here in Milwaukee.

Ms. KRUGER: Oh, we do. Very.

NELSON: Well, perhaps I can just add to that. I mean, Lyn's absolutely right. But to put it on a, you know, better base perhaps, foam is very sexy. Really is. It gives you the tactile properties of the beer, you know, and which is why in this country, if you pour a beer too cold, and particularly down the side of a glass, you're not going to get any foam. And that's a shame, because brewers put a lot of effort and all the people here in the panel here put a lot of effort to actually make beer with good foam. And Lyn's right. The CO2 in the beer will actually give you foam. But if you want a denser, a more creamy foam, nitrogen gas and nitrogen is in the widgets which you speak about, will actually do that. And that's released as you open the bottle or the can.

FLATOW: Why do we drink beer so much colder here, than they do across the pond? What is the tradition, and why, do we brew it differently for that reason? Kirby?

Mr. NELSON: Well, that's - a lot of folks at, in our end of the industry, the special industry, call them, light beers that are very well made, but very mild, lawn mowers. Because after you're done cutting the grass on a super hot day, they're good and cold, you open up and bang! It's gone. You know, but by their nature, they're not very intensely beers, and they're - when they're chilled quite a bit, tend to lose some of their flavor. The great late beer writer Michael Jackson once said Americans tend to chill their beer into insensibility. Which means, when something's too cold, the flavor doesn't come through. And milder American beers were eventually looked at as, at least from my standpoint, being a very, very thirst-quenching liquid. And their flavor became milder over time as they became more mass marketed. So again, it became more of a very pleasant chilled sensation.

FLATOW: And so it was sort of a marketing technique thing?

Mr. NELSON: Again, someone once said the best way to mass market something is to offend the least number of people possible. And so beers were made you know, very, very well made. But you know, a little bit milder, per se, in this country. And it just became of habit. I mean, when I walk into a, you know, establishment that serves our beer and they say, oh you're going to love this. And they hand me a bottle of our beer at about 32 degrees in an iced mug, it's OK. Gee thanks. Then when they turn around, I'm putting them under my arms trying to heat them up.

(Soundbite of laughter)

Mr. NELSON: But yes, it's a cultural thing. There's always misperception.

FLATOW: Well, that's why we see some of the advertising having the word cold in it, and let me go through some of it. And we say, what is it meant when the beer is cold filtered? I mean, it says to the people who like cold beer, hey, this is even colder than you think it is. What is it, does it mean anything more than an advertising slogan? What is cold filtered? Anybody know?

Mr. NELSON: Microbiological stabilization.

(Soundbite of laughter)

FLATOW: We went, a few years ago, we did a show from St. Louis when Anheuser-Busch was on, and besides Miller, one of your great competitors And I asked them, what is beechwood aging? And the chemist who - the biologist that came on said, well, it's more of a marketing tool than it was anything really. And no one else could do it. We did it with beechwood chips. They do it with other kinds of things, but it is the same thing that is going on inside the vat. So there, it looks like a lot of these things, you know. What is an ice beer? Want to know what an ice beer is? You see advertising for that.

Mr. RYDER: It's when you take a beer and to concentrate a little bit you start freezing the water out of it. One of my all-time favorite styles of beer is an eisbock which in Germany you take a doppelbock which is a very strong rich wonderful liquid to begin with. And then in terms in marketing, they are very inefficient to make and to make it a complete loss leader, you start freezing the water out of it. So you're, you know, decreasing the yield you get out of the liquid and what that does is that concentrates the constituents that give the beer its flavor and personality.

FLATOW: 1-800-989-8255. Let's go to the audience here for a question.

BRIAN (Audience Member): Hi, Brian Bartel (ph). First of all, Ira, there is a beer out there called the Holy Grail Ale. So, if you're searching for that beer - there you go. We talked a little bit about, from Russ about an organic beer, but what effect has genetic engineering had on the industry and not necessarily GM Beer or anything, but how does that affect it?

Mr. RYDER: Perhaps I can start on that one. We don't use any genetically modified organisms at all. There's very little genetically modified barley around. I guess there's some, sort of, you know, with GM corn. There's no GM hops. And we've been using the same yeast for 150 years, so, and that's definitely not genetically modified. So, it really doesn't have a - it's really not a big deal in our industry, although perhaps there are some countries and perhaps Lyn wants to expand on that, in terms of where they might use GM materials.

Ms. KRUGER: To the best of my knowledge, in fact, all breweries that I'm aware of do not use any GM raw materials of any kind. Sometimes by default, I mean some of the adjuncts - corn, most corn is genetically modified. So if you're using corn, I think by default you're using a grain that's at some point had some genetic modification, but certainly as far as the malt, the hops - no, no one that I know of.

FLATOW: Russ, let me ask you a couple of questions about some of these, I might call them designer beers that you make. One, is it true that you make beers, a cherry beer that is made with real cherries?

Mr. KLISCH: Yes, we use Door County cherries in our cherry beer. We started making around 1992, and we put them right in the fermenter so we tried to use the state's local ingredients here in making different flavors with our beer. And it goes, there is a Mount Morensee(ph) cherry that we use. It gives off a little tarter flavor, not a sweeter flavor as compared to some other cherry beers.

FLATOW: Is it also true that you make a gluten-free beer?

Mr. KLISCH: Yes, three years ago we got - the government okayed us to make a gluten-free beer called New Grist. We're the first brewery in the country to get authorization to do that. We make it with rice and with sorghum. And so it gives a certain little different taste. It is almost like a Belgian-style beer. And we've received a lot of letters from a lot of people out there saying thank you for that one.

FLATOW: Let's go to the phones, 1-800-989-8255. Paul in Smithtown, New York. Hi, Paul.

PAUL (Caller): Hi, how are you doing? You know, I agree with one of your panelists that was just saying about the freshest beer is delivered from the keg. However, if people do not keep those lines cleaned for the delivery system, they don't have them blown out all the time, the beer will taste terrible. It will have a great effect on the taste of the beer, which is a (unintelligible) effect.

FLATOW: A lot of our panelists are shaking their head in agreement with you. Lyn, you are a beer-tasting expert.

PAUL: Do they agree?

Ms. KRUGER: Yes, think you are quite right. Draft beer as David said is fresh than the brewery ones, you could have it fresh, but the management of draft beer systems at the retail outlet is really critical. If they don't clean the lines, if they don't sanitize - Kirby was talking about how important it is to sanitize it so that you don't get microbial contamination. Then you get what we call beer-spoiling organisms that grow in the lines and that is what changes the flavor of the beer and makes it taste quite sour and buttery and various other off flavors you get from poor management of draft beer systems.

FLATOW: I hate it when that happens.

Ms. KRUGER: Yes.

Mr. RYDER: Well, you know the brewers are very concerned about this at the moment. In fact there is a consortium of brewers between Miller, the Anheuser-Busch, Sierra Nevada and others. Such as you know, Russ at the end there. They are very concerned - and Kirby - that they want draft beer to be served out of clean lines. We want the rigor taken to beer to make sure that taps are clean, lines, are clean, everything is clean because that is the way the customer deserves to have a nice fresh, cold beer.

FLATOW: When are we going to be done here? OK, let's go out to the caller right here.

Unidentified Man (Caller): Thank you. Given the science about the chemistry of the water that you using in the beer, some years ago when I was trying to dispel the myth that we had an unlimited supply of ground water, people cited that we were getting our water from God's country way up north which was a myth. It was a local precipitation. So, could you speak to the water that you're using and the difference of the chemical composition of water from the Great Lakes as processed by municipal water supplies and the water from artesian wells or general ground water.

FLATOW: Or the Rocky Mountains and things...

Unidentified Man: Or from the Land of Sky Blue Waters or the Rocky Mountains - that whole marketing ploy, but actually the water is coming from ground water, from local precipitation within a few miles of the plant most likely.

FLATOW: All right, good point. Anybody want to jump in there? Does the water make that much difference where it counts?

Mr. NELSON: Huge difference. Understand, when someone says hey, that brew is watery, well, most beers are more than 90 percent water, so indeed. And in times gone by, breweries usually sprung up in areas that had a very consistent potable water supply and certain beer styles evolved because of this. And the classic example was British breweries from an area on Burton-on-Trent specializing on a wonderful style called bitter which has a relatively high hopbittering content in regards to the amount of malt. And the beer finishes very dry because of this but there is more to it as we became a little bit smarter and started analyzing these waters. We found out that there is a high permanent hardness i.e. sulphate content in the waters from Burton-on-Trent and that added to that dry finish in the beer.

Now, one of the most common beer - excuse me, brewing water treatments in the world is what is called Burtonizing the water, adding calcium sulphate to the water to get that sulphate character and also calcium's is the most important cation in brewing. And so, the water is very influenced by it. Ourselves, we just use municipal water out of Milton and ionically it is, ironically, very similar to water in Dortmund, Germany.

FLATOW: 1-800-989-8255 is our number. You are listening to Talk of the Nation Science Friday from NPR News. You agree with that, Russ? The water makes a big difference?

Mr. KLISCH: Water makes a big difference. We get our water from the City of Milwaukee which has very good brewing water - one of the reasons why it was a good brewing center here. And one thing you can't do is make beer with distilled water. It is very hard. It has to have a certain amount of minerals in it. The mineral content does play a big factor into beer.

FLATOW: Is there regulation in Milwaukee it has to be good for brewing water of the water coming through? Let's go to Kerry (ph) in Tucson. Hi, Kerry.

KERRY (Caller): Hi, how are you?

FLATOW: Fine. Go ahead.

KERRY: Good, good. Hey, I have a question. Back when I was in high school the drinking age in Arizona was 19, and so needless to say when we got out of high school we drank quite a bit of beer. But then we started on the imported beers because back then like your Millers and your Buds and stuff, they tasted awful. I mean, they were nasty beers, and so we stuck with the imports but now I notice we're kind of going back, at least I am, drinking more American beers because they taste a lot better. I mean, was there actually a big difference back in the '70s and '80s that made them taste kind of bad? I mean...

FLATOW: Good question. Did Miller know this and decided to change its formula or something?

Mr. RYDER: Well, I've always made beers by traditional methods but I will say that through research and development that the actual quality of the brewing materials has become better. So, the quality of the barley, which is malted, the quality of the hops, making sure - to the previous question that we have, consistent water quality. So, all these and of course, as I said earlier, making sure the yeast is happy. Sad yeast will not make a good beer. So you have to have it happy.

FLATOW: Happy yeast. I think - one quick question we have time for.

Unidentified Woman (Audience Member): Just a quick question. My friend recently came back from - she's an entomologist, and a conference. And they had perfected their beer they call bug beer. And they had extracted the yeast from the bark beetle.

FLATOW: I'm glad I kept this for the last.

(Soundbite of laughter)

FLATOW: They took the yeast from the bark beetle. Do they make beer out of it?

Unidentified Woman: They used from the bark beetle and made beer out of it, used it to make beer. And I was just wondering, the most interesting beers that you'd had.

FLATOW: Well, what do you think, Russ, bark beetle? Cherries?

Mr. KLISCH: Maybe that's the Holy Grail Beer there.

FLATOW: What is the most interesting beer that you ever had?

Mr. KLISCH: I'm trying to think. I'd probably say some of the European styles and maybe from Belgium that we'd had - of the different styles of yeast that they've had. Everytime you open a different one, there's great flavors from the lambics and the gueuze.

FLATOW: Do any of you decide what you're going to settle on, what kind of flavor? Is that just a personal decision that you make?

Mr. KLISCH: Yes, that is a personal decision, you know, being a brewer is like being a chef. You always have to have this one thing in your mind which you think is going to have the best flavor - and you shoot for it.

FLATOW: Kirby, do you agree? It is a personal decision?

Mr. NELSON: Very much. And I will say the most interesting beer I was ever offered, I declined to try it, was a home brewing gentleman. He decided to use Beano throughout the process.

FLATOW: Beano.

Ms. KRUGER: I think the most interesting beer I've ever had is a watermelon beer. Really tasted like fresh watermelon at the Great American Beer Festival, if any of you want to go there. It is a great opportunity. They have it in Denver every year in about September, October, to try lots and lots of different beers. I think they just had the World Beer Cup. They're 91 recognized different beer styles and they have about 600 at least breweries there that you can taste a huge variety of beers you can't taste anywhere else...

FLATOW: David can you...

Mr. RYDER: And the most interesting beer that I have had is the one I drink at the moment.

FLATOW: The one you have in your hand.

Mr. RYDER: Yes, it's just wherever you are because whether it is a Trappist beer from Belgium, if you're in Belgium, whether it's a good American beer here, whether it is a good British bitter, that is the most interesting beer. You know, beer is to be discovered. Now, it encourage all of you under moderation of course, to be able to discover the world of beer.

FLATOW: That is David Ryder, vice president of Brewing Research and Quality Assurance at Miller Brewing Company. Thank you, David for joining us today. Kirby Nelson is the brewmaster for Capital Brewery in Middletown, Wisconsin. Thank you. And Lyn Kruger, president and chief operating officer of the Siebel Institute of Technology in Chicago. Thank you, Lyn. Russ Klisch, president and founder of Lakefront Brewery right here in Milwaukee. Thank you for taking time to be with us today.

Greg Smith composed our theme music. And we had help today from NPR librarian Kee Malesky. We'd also like to thank Wisconsin Public Radio on WHAD for inviting us. Also thanks to Sammy Luminour (ph) from WPR and Robin Ellison(ph) and Rich Shaul(ph) from Milwaukee Public Museum. And we'd like to dedicate this broadcast to the memory of Bill Estes(ph). You have comments or questions, you can write to Science Friday 4 West 43rd Street, Room 306, New York, New York 10036, surf over to our website for our blogging and podcasting and some video that we'll have coming out of this broadcast of Science Friday. We'll see you next week back in New York. I'm Ira Flatow in Milwaukee.

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