Beer Tapping Physics

The Division of Fluid Dynamics of the American Physical Society sent out a press release about a new study a couple of their members recently published on cavitation, which is a word you’ll understand better from the description.

An old, hilarious if somewhat juvenile party trick involves covertly tapping the top of someone’s newly opened beer bottle and standing back as the suds foam out onto the floor. Now researchers from Carlos III University and Universite Pierre et Marie Curie, Institut Jean le Rond d’Alembert, have produced new insight into the science behind the foaming, exploring the phenomenon of cavitation.

Take a look at the release, The Physics of Beer Tapping Fluid Dynamics Explains Why Bottled Beer Bubbles Over When Tapped, and thanks to regular reader Russ R. for sending me the link. I like this explanation a bit better, though.

“Buoyancy leads to the formation of plumes full of bubbles, whose shape resembles very much the mushrooms seen after powerful explosions,” Rodriguez-Rodriguez explained. “And here is what really makes the formation of foam so explosive: the larger the bubbles get, the faster they rise, and the other way around.” He adds that this is because fast-moving bubbles entrain more carbonic gas.

Honestly, I don’t think I’ve ever done that to a person’s bottle. Of course, I tend to be around people who pour their bottle of beer into a glass.

Photo: Javier Rodriguez-Rodriguez / Carlos III University of Madrid, SPAIN Almudena Casado-Chacon / Carlos III University of Madrid, SPAIN Daniel Fuster / CNRS (UMR 7190), Université Pierre et Marie Curie, Institut Jean le Rond d’Alembert, FRANCE

The Science Behind Sobriety Tests

Today’s infographic is all about the Science Behind Sobriety Tests, and especially the three most common field tests that police officers administer on the side of the road when they suspect that someone might be driving with blood alcohol over the legal limit. It was created by Total DUI, a legal website specializing in helping people facing DUI/DWI charges.

Click here to see the infographic full size.

Selecting And Generating Superior Yeasts For The Brewing Industry

After my post a couple of days ago about Genetically Engineered Yeast, Chaz from Alaskan Brewing sent me a link to an interesting blog post by Dmitri, an amateur yeast wrangler who writes about his yeasty adventures at BKYeast. The post is a review of science literature from Cerevisia, the Belgian Journal of Brewing and Biotechnology. The article in question is titled Selecting and Generating Superior Yeasts for the Brewing Industry, which was published in 2012. It’s deliciously geeky and technical, but should be scrutable to anyone who brews either professionally or at home, thanks to Dmitri’s writing, as his goal is to take the jargon and science and make it accessible to a broader audience. As brewers struggle to have their beers stand out in an ever-increasingly crowded marketplace, it should be obvious that we’ll be seeing more and more experimentation with flavors and ingredients and ultimately more unique beers, and even new types of beers as others copy the successful ones, in the coming years. As the author notes, new varieties of hops are already facilitating that effort, and it seems likely that new strains of yeast are a logical next step in that evolution. And that’s what this research by a group from Leuven, Belgium is trying to make easier, finding the right yeast to create the right range of flavors for your beer. Give it a read.

“Graphical representation (heat map) of different characteristics of industrial yeast strains. Every row consists of data from a different yeast strain, every column is a different characteristic. ‘Yellow’ is a low score, and ‘red’ is a high score for this certain characteristic. The dendrogram on the left represents the genetic relatedness of the yeasts, based on an AFLP fingerprint exploiting transposon TY1 insertion site polymorphisms. The colour code on the top right indicates the origin of the yeast strains. This kind of analysis allows us to select yeasts with specific beneficial traits, for example to use in industry, or for breeding.”

Genetically Engineered Yeast

Mashable had an interesting piece about Genetically Engineered Yeast being done by at least two companines, Amyris and Evolva, and based in part on a New York Times article, What’s That Smell? Exotic Scents Made From Re-engineered Yeast. In the Times article Amyris co-founder Jay Keasling explained “that the process is ‘just like brewing beer, but rather than spit out alcohol, the yeast spits out these products.’” The relatively new discipline, dubbed synthetic biology, is only about a decade old. There are apparently issues about whether it would be considered natural. SOme say no, because the synthetic version “contains scores of components besides” what it’s being used as, while John B. Hallagan, from the Flavor and Extract Manufacturers Association believes “it conceivably could be called a natural ingredient since it is made in a living organism.”

Curious Cautions On Consumption Of Alcohol

It’s not sure what to make of some news that’s being reported based on a new report by the Alcohol Research Group of Emeryville, California. Several news outlets have picked up the story, including the San Francisco Chronicle, in Sobering tip – drink makers alter alcohol content; Join Together, in Drinks Often Contain More Alcohol Than People Realize; and Health magazine, in How Much Alcohol In Your Drink? Stronger Beverages Make It Tough to Tell.

The first curiosity is some articles say the report was done by the Public Health Institute’s Alcohol Research Group while others claim it was the National Alcohol Beverage Control Association. Curiouser still is the fact that neither organization has any information I can find about the alleged report, which is odd since the news reports quote people involved in it and from it. It’s not uncommon for only a summary to be available, especially if they’re trying to sell it to people, but I can’t even find any reference to it at all. It’s also fairly common for there to be a press release summarizing the report, but I can’t locate one of those, either. The NABCA in their news section has a link to a report on their report on Health24, the same syndicated article by Brenda Goodman that many news outlets are using. You’d think they’d at least have their own story about their own report.

Although the articles concern themselves with this new report, not one of them even mentions its name, although they each quote the report’s author, William Kerr, who’s billed as “a senior scientist with the Alcohol Research Group.” Scientist seems like a stretch, since his background is not in the hard sciences, having a BA and a PhD, both in economics. Now I have nothing against economics whatsoever, in fact I love the dismal science, and am fascinated by it. I know it’s a social science, a concept I fully accept, but when’s the last time you ever heard an economist referred to as a scientist, or even a social scientist? Having the title “senior scientist” strikes me as just a tad misleading, or is that just me?


Anyway, the point of the report, from what I can piece together, is that the standard drink sizes that are generally used determine as a single drink (mind you, for purposes of research and making people feel guilty, not for our real lives) are not as effective as they once were, because the alcoholic strength of beer and wine varies, and many people are too stupid to realize that. It honestly strikes me as a tempest in a teacup at the very least, and an attempt to fan the flames of anti-alcohol mischief at worst.

Here’s how one of the articles begins. “Thanks to rising alcohol levels in wine and beer, the drinks served in bars and restaurants are often more potent than people realize, a new report shows.” Seriously, just now rising? I know there are perhaps more higher strength beers than before the 1980s, when most beer was all the same, and certainly since craft beer is getting more popular arguably more of it’s being sold, but it’s still a drop in the ocean of the 5% beer majority. And really, is wine getting stronger? The report’s author, William Kerr, is quoted, saying “A lot of the wines now are 14 percent or even 15 percent commonly, and the standard 5-ounce glass of wine doesn’t apply to that level.” Um, as long as I can remember 14% has been the average wine strength. Seriously, if you had asked me how strong wine typically is, that would have been my immediate response. Of course, I’m no wine expert, by any stretch of the imagination, so I’ll defer to my wine brethren on that one. A Guardian article from 2011 reveals that it’s closer to 13% worldwide and 13.65% in the “New World,” by which I assume they mean us upstarts in the colonies. But if the averages are higher than what the “guidelines” are based on, wouldn’t it make more sense to argue for changing them, instead of complaining that people aren’t converting them properly? If they’re really concerned that people are drinking too much because of their own information, then changing it seems a more obvious solution to me.

Here’s another one I don’t quite understand. “Beer drinkers may find themselves in the same boat. A 12-ounce bottle of Bud Light beer has 4.2 percent alcohol, but the same-size bottle of Bud Light Platinum has 6 percent alcohol by volume, a nearly 50 percent increase.” I know math is hard, but that seems to skew the numbers to stretch a point. A 4.2% beer would contain .0504 ounces of alcohol, while at 6 percent, the amount would be 0.72. While ordinary rounding you could argue might make sense in other contexts, when you’re talking about such small numbers, the effect of rounding is inflating by one-half a percent (0.5%), not an inconsequential amount when the difference between the two examples is only 1.8%. That seems designed to make that example seem worse than it really is.

They also mention that it “matters whether you’re drinking a standard 12-ounce bottle, or downing draft beer in pints, which are 16 ounces each.” And that’s partly true, it does make a difference, but most good beer bars don’t serve higher alcohol beers in pint glasses, but in a smaller glass that’s less than that.

The Chronicle’s report claims that “craft beers and European imported beers usually have alcohol content a few percentage points higher than major American beers.” Some, sure, but their point is that beer strength varies widely, but then they give this absurd generality that’s not remotely true.

Also in the Chronicle, Kerr tells us that “Federal law requires hard alcohol manufacturers to list the alcohol content by volume on labels, but it’s optional for beer and most wines.” Actually, it’s the states that determine that, and in California it is indeed required on the label. Given that Kerr is in California, and the article was written by and for a California audience, that seems like it could have been useful information. It’s not optional here, nor do I believe that’s the case for any other state.

One thing I do agree with is the statement by Robert Pandina, director of the Rutgers Center of Alcohol Studies, who posits that the “dietary guidelines aren’t very useful. They don’t parallel the drinking habits of the American public.” So why we keep using them, I think, has more to do with people involved in the addiction business and anti-alcohol groups, then wanting to honestly come up with something that most people can actually use. Tellingly, Pandina is not part of the report that’s the subject of the articles.

The overall tone of the advice from the report, at least as gleaned from the quotes from it, is that people should be ridiculously fastidious in monitoring their intake of alcohol. But the guidelines are not that exact, nor should they be. The UK’s recommended amounts in fact were simply made up, while ours were more likely based on average drink sizes from once upon a time, and became fixed in stone along the same lines as binge drinking became increasingly narrowly defined. This, I can only guess, is the result of working with or around people with drinking problems. Most of us can manage to drink responsibly and moderately without a measuring cup or journal. If the majority of people who drink alcohol are not problem drinkers, which is the case, then being sensible doesn’t require a calculator. Most people know their limits and can, and do, moderate their own behavior and probably do so intuitively, having learned their own limits. I know mine, don’t you?

The headline that the “alcohol content of beer and wine varies widely” seems almost insulting in its assumption that most people think it’s all the same. I may not be among the average drinkers, but the news that different drinks have varying strengths seems too obvious, especially when you consider that the usual argument for not listing strength is that everyone will start shopping the labels and buy the strongest drinks to get drunk faster. So on one hand, us drinkers are smart enough to game the system by reading the labels to get drunk quicker, yet we’re too stupid to realize that different drinks have different amounts of alcohol in them. How many people honestly still believe that all beer is the same in 2013? Maybe it’s just the air of superiority that the prohibitionists and parts of the medical community adopt when they talk down to us in the world that continues to rankle. But I’ll sleep better tonight in the knowledge that by drinking moderately and responsibly, I’ll most likely live longer than the teetotalers who look down upon me and my ilk.


On Geeks & Nerds & Snobs

The definitions of how we follow our passions seems to be a popular topic of discussion lately. Are we geeks, nerds, snobs, enthusiasts, connoisseurs or aficionados, or just annoying? I tackled this question in my first article for Beer Advocate magazine, way back in 2007, in “Freaks and Beer Geeks.” In that piece, I defined a geek as “an obsessive enthusiast, often single-mindedly accomplished, yet with a lingering social awkwardness, at least outside the cocoon of their chosen form of geekdom.” I’m still pretty happy with that definition, it seems to fit most of the geeks I know. And as I’m one myself — something I gleefully admitted in Living in the Silver Age for All About Beer — I tend to prefer being around other geeks. In my experience, we tend to run in packs. We’re tribal.
Here’s what I said in early 2007.

Beer Geeks. You probably know one of us. Hell, if you’re reading this magazine you may be one, too. And even if you don’t or you aren’t, you probably know what we’re talking about. We’re the Trekkies — excuse me — Trekkers of the beer world. You can find us at our countless conventions — a.k.a. beer festivals — wearing the uniform: beer t-shirt (occasionally tie-dyed), denim, baseball cap with brewery logo and in winter a hoodie, ditto logo. We’ll go anywhere in the world to find great beer.

We are also known by other names: snob, fanatic and hophead, among others. But fanatic never quite caught on, hophead is generally reserved for fans of IPAs and other hoppy beers, and snob never crossed over, retaining its mostly derogatory meaning. Originally, a snob was someone who made shoes, a cobbler, before migrating to a person of the lower classes who wants to move up and then on to its present meaning of a person who places too much emphasis on status or “a person who believes that their tastes in a particular area are superior to others.”

Occasionally kinder, gentler terms are employed like enthusiast or aficionado, but they never seem to strike the right chord for some reason. Most of us prefer to be known simply as beer geeks though, oddly enough, the word geek meant originally a fool and later referred to the lowest rung of circus performer, one who may even have bitten the heads off of live chickens, as popularized in a 1946 novel, “Nightmare Alley,” by William Gresham, about the seedy world of traveling carnivals. In that book, to be a “geek” was to be so down and out that you’d do virtually anything to get by, no matter how distasteful or vile.

Like many old words that were primarily derogatory, its meaning has now been turned on its head. Beginning probably with the original new nerd, the computer geek, it was taken back as a source of pride. So today there are band geeks, computer geeks, science geeks, film geeks, comics geeks, history geeks and Star Wars geeks, to name only a few, all of them proud to call themselves geek, because of the shared passion that is so central to its modern meaning. Today a geek is an obsessive enthusiast, often single-mindedly accomplished, yet with a lingering social awkwardness, at least outside the cocoon of their chosen form of geekdom.

But then there’s the on-going debate about whether we, or anybody really, is a geek, a nerd, a dork, a snob, or whatever. Not that these labels matter, but they must at least a little bit, since people keep talking about them.
Beer Geek Speak last year asked Snob, Geek or Nerd…Which are you??, Anti-Hero Brewing also tackled Beer Geek vs. Beer Snob and Modern Drunkard has the Subtle Art of Beer Snobbery. The point is, do a Google search for geek vs. nerd or geek vs. snob and you’ll get a lot of hits, and most of the top ones, particularly comparing geeks and snobs, are about beer drinkers. Clearly, this is on our minds.

I think a lot of this is coming from the fact that beer is trying to climb out of the muck and ooze that has kept it down for decades, kept it a drink of of the hoi polloi, with many manufacturers more worried about quantity than quality. Changing that has been a struggle, for a variety of reasons, but the notion that beer is every bit as sophisticated and worthy of respect as any other beverage has been difficult to achieve. Why that is would make for an entire book, a very thick book even, but this endless debate over labels is just one manifestation of that, I believe. And so we see the endless comparisons to wine, which annoys many of us to no end. I’ve written extensively about my own frustration with this, and earlier today Jen Muehlbauer had a terrific piece on that very subject: Fancy beer: pinkies out or middle fingers up?

Earlier this morning, a UK colleague, Phil Mellows, shared an interesting article from Slackpropagation entitled On “Geek” Versus “Nerd”, first published this June. A more general discussion, in it author Burr Settles defines a geek as an “enthusiast of a particular topic or field,” saying “Geeks are ‘collection’ oriented, gathering facts and mementos related to their subject of interest. They are obsessed with the newest, coolest, trendiest things that their subject has to offer,” whereas a nerd he defines as a “studious intellectual, although again of a particular topic or field. Nerds are ‘achievement’ oriented, and focus their efforts on acquiring knowledge and skill over trivia and memorabilia.” He later draws a further distinction, saying this. “Both are dedicated to their subjects, and sometimes socially awkward. The distinction is that geeks are fans of their subjects, and nerds are practitioners of them.”

He then mined the data from several million tweets to create a statistical model showing geeks and nerds plotted on an x/y axis showing their relative geekiness and nerdiness. Here’s how he described the results:

The PMI statistic measures a kind of correlation: a positive PMI score for two words means they ”keep great company,” a negative score means they tend to keep their distance, and a score close to zero means they bump into each other more or less at random.

With that in mind, here is a scatterplot of various words according to their PMI scores for both “geek” and “nerd” on different axes (ignoring words with negative PMI, and treating #hashtags as distinct):

And here is the plotted chart, though I added beer since his data didn’t include beer geeks or beer nerds. And frankly, I just picked a hole where I thought beer might fit, but I really can’t say where beer would properly fit along the continuum. Where do you think it belongs?

Click here to see the original chart full size.

To me, this is interesting stuff, even though in the grand scheme of things none of it really matters. As long as you’re comfortable in your own skin and know who you are, what people call you you or even how you label yourself means almost nothing. But where we fit into the world does matter, at least to each of us, so I think that’s probably why I find this fascinating. We may not be able to pick our family, but our friends, our passions and the tribes we join do matter deeply and on a very personal level. They form a part of the architecture by which we define ourselves. I identify myself as a beer drinker, and that means something to my self-image, as I imagine such labels do to most of us. It’s how we see ourselves and present ourselves to the world. It only seems to go wrong when other people choose the labels for us. For example, I’m fine with geek, and nerd doesn’t bother me, but I don’t care for snob, even though I can think of plenty of instances when I have been a snob. In part, it’s a perception of the words as labels themselves. They’re not static, but in constant flux, their meaning changing subtly all the time.

And here’s one final bit of interest. In the comments, there’s one from a Hannah Fry, who’s the host of Number Hub, part of a British YouTube channel started by James May called Head Squeeze. After this post was initially published, she entertainingly devoted one of her weekly videos to the question of what distinguishes geeks and nerds. Enjoy.

The Beer-Smell Gene

Time magazine’s health section had a recent article — The Beer-Smell Gene and Other Ways DNA Drives Our Senses — about how are sense of smell functions, and that not everybody smells things the same way, in the same way that the color blue may look slightly differently to some people (especially those who are color blind). Of course, that’s something any experienced beer judge could tell you. One of the things that you learn, especially when you judge with the same group of people many times, is that everybody’s tolerances and sensitivities to different aromas varies widely. I, for example, am quite tolerant of diacetyl and have to be hit over the head with it to notice it. Mercaptans, on the other hand — that hoppy cat piss — I’m so sensitive of I only need get the glass near my nose to detect it. And we all have those quirks. I’ve judged on the Celebrator Beer News tasting panel with the same group of people for over ten years now, and I can safely predict what my fellow panelists will say about many of the beers we taste.

But what this new study (in the journal Current Biology) found is that “our senses are intimately connected to our DNA, and small variations in our genes can determine whether we are partial to the smell of blue cheese, or can’t stand the taste of cilantro.” The study itself noted. “Analysis of genotype frequencies across human populations implies that variation in sensitivity for these odors is widespread.” This suggests, not surprisingly, that what we find in beer-tasting is true across the broad spectrum of how food smells and tastes, so that in a very real sense none of us taste the same food (or drink) in exactly the same way. Clearly, as a group things do taste similarly to most of us, but there appears to be enough variance that we can’t ever say universally how something should or does taste.

What’s new in this study is that scientists are now able to trace such predispositions to our genomes and are finding patterns based on our DNA and genetic makeup. Interestingly, is also found that “sensitivity is heritable,” meaning how things taste to you is likely similar to your parents and other members of your family. I also love this quote from the abstract, which sums it up neatly. “[E]ach participant possessed one of many possible combinations of sensitivities for these odors, supporting the notion that everyone experiences their own unique ‘flavor world.’” The lead scientist on the study, Jeremy McRae, notes “that when people sit down to eat a meal, they each experience it in their own personalized way.” Which may also explain why I (and presumably you, too) have a taste for beer, while some people simply do not.


Mosquitoes Prefer Beer Lovers

There was an interesting article recently in the Smithsonian’s Surprising Science entitled Why Do Mosquitoes Bite Some People More Than Others? The article provides a good overview about why some people get bitten more frequently than others, and some of the causes believed to account for this very real phenomenon.

An estimated 20 percent of people, it turns out, are especially delicious for mosquitoes, and get bit more often on a consistent basis. And while scientists don’t yet have a cure for the ailment, other than preventing bites with insect repellent (which, we’ve recently discovered, some mosquitoes can become immune to over time), they do have a number of ideas regarding why some of us are more prone to bites than others.

Some of the factors include blood type, carbon dioxide, exercise and metabolism, pregnancy, skin bacteria, the color of your clothing and even genetics. But the interesting one that stood out for me, of course, was beer.

Just a single 12-ounce bottle of beer can make you more attractive to the insects, one study found. But even though researchers had suspected this was because drinking increases the amount of ethanol excreted in sweat, or because it increases body temperature, neither of these factors were found to correlate with mosquito landings, making their affinity for drinkers something of a mystery.

That beer is a mosquito attracter was confirmed by a study with the wonderfully bland title Alcohol ingestion stimulates mosquito attraction (seriously, who comes up with the titles for journal articles, so often they’re just dreadful). Of course, even though they know that it’s true that drinking alcohol attracts more mosquito bites, they still haven’t a clue why.

I’d love to see a study of different kinds of beer to see if any particular kind is more attractive to mosquitos than another. Can you imagine the ad copy following that study? “Drink our beer at your next picnic and mosquitoes will leave you alone!”