The Secret to a Frothy Stout

Here's your annual "how does draft Guinness work?" article, courtesy of LiveScience. This one describes a new twist on the old widget:

Applied mathematicians in Ireland recently discovered a possible replacement for the widget that is not only eco-friendly, but could be cost-effective for brewers. They published their findings in the Mar. 8, 2011, issue of the journal Nature.



Graduate student Michael Devereux, supervised by William Lee of at the University of Limerick in Ireland, discovered that microscopic plant fibers can froth stout as well as a widget.



"Our proposed alternative to the widget would consist of an array of cellulose fibers of approximately three square centimeters," said Devereux. "Our research suggests that stout could be made to foam using an array of fibers in 30 seconds, which is the time it typically takes to pour a glass of stout."



Inside of a nitrogen-enriched stout, pockets of air trapped inside cellulose fibers become seed bubbles that trigger nucleation (the formation of additional bubbles). As nitrogen and carbon dioxide diffuse through the walls of the fibers, the seed bubbles grow. When each bubble reaches a certain length, it detaches and breaks off of the gas pocket and floats to the top of the liquid. This process is repeated until the gas dissolves completely into the stout.

Read the whole story at LiveScience and at Nature, where one of the researchers says, ""We've spoken to brewers, but we're not sure if they're interested yet."

Favorite styles

I am often asked what my favorite style of beer is. Of course, this question is just as difficult to answer as the "favorite beer" question. But I thought I'd ask my database what it thinks my favorites are, and here's what it came up with:

+-----------+-----+--------------------------------------------------------------+
| score     | n   | style                                                        |
+-----------+-----+--------------------------------------------------------------+
| 18.785714 |   7 | Other Belgian-Style Sour Ale                                 |
| 18.750000 |   2 | Black IPA                                                    |
| 18.000000 |   1 | American-Style "Light" Amber Lager                           |
| 18.000000 |   1 | Dark American Wheat Ale or Lager without Yeast               |
| 17.938776 |  49 | Wood- and Barrel-aged Strong Beer                            |
| 17.666667 |  24 | Belgian-Style Gueuze Lambic                                  |
| 17.607143 |  14 | Imperial or Double Red Ale                                   |
| 17.562500 |  16 | Wood- and Barrel-aged Dark Beer                              |
| 17.506849 |  73 | Imperial or Double India Pale Ale                            |
| 17.348485 |  33 | Coffee Flavored Beer                                         |
| 17.323529 |  17 | Wood- and Barrel-aged Beer                                   |
| 17.218750 |  16 | German-Style Eisbock                                         |
| 17.200000 |   5 | Strong Ale                                                   |
| 17.166667 |   3 | European-Style Low-Alcohol Lager / German-Style Leicht(bier) |
| 17.100000 |  10 | Other Belgian- and French-Style Ale                          |
| 17.060000 |  25 | Baltic-Style Porter                                          |
| 17.059524 |  42 | Belgian-Style Flanders/Oud Bruin Ale                         |
| 16.894309 | 124 | Imperial Stout                                               |
| 16.864341 | 129 | Belgian-Style Dark Strong Ale                                |
| 16.834783 | 115 | Belgian-Style Pale Strong Ale                                |
| 16.833333 |  30 | Bamberg-Style Rauchbier                                      |
| 16.833333 |  15 | Experimental Beer                                            |
| 16.833333 |   6 | American-Style Strong Pale Ale                               |
| 16.684874 | 243 | Barley Wine-Style Ale                                        |
| 16.654762 | 128 | Old Ale                                                      |
| 16.615385 |  13 | South German-Style Bernsteinfarbenes Weizen/Weissbier        |
| 16.595833 | 122 | German-Style Strong Doppelbock                               |
| 16.586957 |  23 | Chocolate/Cocoa Flavored Beer                                |
| 16.578125 |  32 | Belgian-Style Pale Ale                                       |
| 16.541667 |  36 | South German-Style Weizenbock/Weissbock                      |
| 16.516667 |  60 | Other Belgian-Style Ale                                      |
| 16.500000 |  10 | Modern Strong Scotch Ale                                     |
| 16.470588 |  17 | Standard Cider / Perry                                       |
| 16.350000 |  10 | American-Style Stout                                         |
| 16.333333 |  27 | Other Strong Ale or Lager                                    |
| 16.322430 | 107 | Belgian-Style Tripel                                         |
| 16.316176 |  68 | French-Belgian Style Saison                                  |
| 16.285714 |  21 | French-Style Bière de Garde                                  |
| 16.281250 |  48 | Smoke-Flavored Beer (Lager or Ale)                           |
| 16.268657 |  67 | Belgian-Style Dubbel                                         |
| 16.245614 |  58 | South German-Style Dunkel Weizen/Weissbier                   |
| 16.195205 | 146 | Specialty Beer                                               |
| 16.184000 | 381 | American-Style India Pale Ale                                |
| 16.166667 |   6 | Belgian-Style Lambic                                         |
| 16.162879 | 136 | Herb and Spice Beer                                          |
| 16.133333 |  15 | NULL                                                         |
| 16.106061 |  33 | Foreign (Export)-Style Stout                                 |
| 16.078358 | 134 | Münchner-Style Helles                                        |
| 16.000000 |   2 | Specialty Cider / Perry                                      |
| 16.000000 |   6 | Non-Alcoholic (Beer) Malt Beverage                           |
| 16.000000 |   2 | American-Style Malt Liquor                                   |
| 16.000000 |   9 | Berliner-Style Weisse (Wheat)                                |
| 15.926471 |  69 | Traditional Strong Scotch Ale                                |
| 15.858491 | 108 | Oatmeal Stout                                                |
| 15.833333 |   3 | Leichtes Weizen/Weissbier                                    |
| 15.833333 |   3 | Braggot                                                      |
| 15.815789 |  19 | Garden (Vegetable) Beer                                      |
| 15.792857 |  70 | German-Style Schwarzbier                                     |
| 15.791667 |  12 | American-Style Premium Lager                                 |
| 15.776316 |  38 | Belgian-Style Fruit Lambic                                   |
| 15.760870 |  47 | Dortmunder/European-Style Export                             |
| 15.750000 |  10 | Scottish-Style Light Ale                                     |
| 15.746183 | 262 | South German-Style Hefeweizen/Hefeweissbier                  |
| 15.740838 | 191 | German-Style Pilsener                                        |
| 15.695455 | 111 | Sweet Stout                                                  |
| 15.649123 |  57 | Classic English-Style Pale Ale                               |
| 15.617021 |  96 | German-Style Heller Bock/Maibock                             |
| 15.602273 |  44 | Irish-Style Red Ale                                          |
| 15.556000 | 125 | Belgian Style White (or Wit) / Belgian-Style Wheat           |
| 15.553435 | 131 | European-Style Dark/Münchner Dunkel                          |
| 15.544444 |  57 | American-Style Brown Ale                                     |
| 15.530612 |  49 | English-Style India Pale Ale                                 |
| 15.500000 |   1 | Other Fruit Melomel                                          |
| 15.500000 |   2 | Bohemian-Style Pilsner                                       |
| 15.500000 |   1 | South German-Style Hefeweizen-Hefeweissbier                  |
| 15.472222 |  18 | Ordinary Bitter                                              |
| 15.454545 |  33 | American-Style Rye Ale or Lager                              |
| 15.397059 |  69 | Scottish-Style Export Ale                                    |
| 15.383065 | 125 | Traditional German-Style Bock                                |
| 15.375000 |  29 | California Common Beer                                       |
| 15.375000 |   4 | American-Style (Extra Special) Strong Bitter                 |
| 15.346154 |  13 | English-Style Dark Mild Ale                                  |
| 15.282328 | 239 | Classic Irish-Style Dry Stout                                |
| 15.280822 | 146 | Bohemian-Style Pilsener                                      |
| 15.263959 | 201 | English-Style (Extra Special) Strong Bitter                  |
| 15.166667 |   3 | American-Style Märzen/Oktoberfest                            |
| 15.132000 | 127 | (Special) Best Bitter                                        |
| 15.127907 |  43 | English-Style Pale Mild Ale                                  |
| 15.090686 | 207 | German-Style Märzen/Oktoberfest                              |
| 15.062500 |  16 | American-Style Pilsener                                      |
| 15.023220 | 331 | Robust Porter                                                |
| 15.000000 |  12 | South German-Style Kristal Weizen/Kristal Weissbier          |
| 15.000000 |   1 | Traditional Mead                                             |
| 14.933333 |  16 | Light American Wheat Ale or Lager without Yeast              |
| 14.928571 |   7 | English-Style Summer Ale                                     |
| 14.915739 | 649 | American-Style Pale Ale                                      |
| 14.839286 |  28 | Scottish-Style Heavy Ale                                     |
| 14.791139 |  80 | German-Style Kölsch/Köln-Style Kölsch                        |
| 14.772727 |  44 | American Lager/Ale or Cream Ale                              |
| 14.720264 | 229 | English-Style Brown Ale                                      |
| 14.712871 | 102 | German-Style Brown Ale/Düsseldorf-Style Altbier              |
| 14.642857 |   7 | Dark American Wheat Ale or Lager with Yeast                  |
| 14.642857 |  56 | European-Style Pilsener                                      |
| 14.637441 | 432 | American-Style Amber/Red Ale                                 |
| 14.610759 | 161 | Golden or Blonde Ale                                         |
| 14.606742 |  89 | Vienna-Style Lager                                           |
| 14.571429 |   7 | American-Style Light Lager                                   |
| 14.486111 |  36 | Specialty Honey Lager or Ale                                 |
| 14.383333 |  30 | Garden (Fruit) Beer                                          |
| 14.271186 |  60 | Brown Porter                                                 |
| 14.083333 |  30 | Australasian, Latin American, or Tropical-Style Light Lager  |
| 14.031250 | 196 | Light American Wheat Ale or Lager with Yeast                 |
| 13.721429 | 210 | American-Style Lager                                         |
| 13.500000 |  22 | American-Style Amber Lager                                   |
| 13.325000 |  20 | American-Style Dark Lager                                    |
| 13.146825 | 127 | Garden (Fruit Wheat) Beer                                    |
+-----------+-----+--------------------------------------------------------------+

Granted, the sample sizes are pretty small for many styles at the top, but I had no idea that I rated barrel-aged beers so highly, nor Imperial IPAs. I thought Bamberg-Style Rauchbier would be much higher on the list. I'm guessing that Altbier is near the bottom because it's so difficult to find fresh, authentic examples in this country.

For the most part, the styles at the bottom of the list are no surprise. I despise fruit beers, with grudging exceptions for well-made fruit lambics.

There are probably more sophisticated statistical techniques for analyzing this, but it's interesting as it is. Think I'll have a beer now.

Does Guinness Beer Taste Better in Ireland?

My own experience is that Guinness does, in fact, taste better in Ireland than it does in the U.S. It's pretty easy to ascribe that to freshness, though. Any beer will taste better closer to its source.

Over a period of one year, four researchers of different nationalities traveled to 14 countries and visited 71 Guinness serving establishments in 33 cities to collect data for 103 tastings.



Tasting scores for pints of Guinness were generally high all around the world, yet tastings in pubs in Ireland scored significantly higher.

Read the whole story at Science Daily.

"Beer Me!" for Android: last call for testers

I just sent version 0.11.0 of the "Beer Me!" for Android app to the testers. It's getting very close to publishing-quality, so this is the last call: if you want to help test the app and be eligible for get it for free when it's available, contact me now.

You want screenshots? We got screenshots!

Main screen

Brewery list

Brewery details

Beer list

Beer notes

…with just a hint of Naive Bayes in the nose

This interesting bit showed up at Language Log this week. I'd like to see it applied to beer reviews as well; I believe the results would be similar.

Using descriptions of 3,000 bottles, ranging from $5 to $200 in price from an online aggregator of reviews, I first derived a weight for every word, based on the frequency with which it appeared on cheap versus expensive bottles. I then looked at the combination of words used for each bottle, and calculated the probability that the wine would fall into a given price range. The result was, essentially, a Bayesian classifier for wine. In the same way that a spam filter considers the combination of words in an e-mail to predict the legitimacy of the message, the classifier estimates the price of a bottle using its descriptors.



The analysis revealed, first off, that "cheap" and "expensive" words are used differently. Cheap words are more likely to be recycled, while words correlated with expensive wines tend to be in the tail of the distribution. That is, reviewers are more likely to create new vocabulary for top-end wines. The classifier also showed that it's possible to guess the price range of a wine based on the words in the review.

Bonus points for the Monty Python reference in the comments.

Disaster! ...almost.

Fired up Eclipse this morning, meaning to make some more progress on my Android app.

Shocked to see all my code, settings, everything...gone.

Scrambled to find my USB drive containing the backup. The twelve-days-and-two-versions-old backup.

# find / -name 'Android*' -print

Relieved to find that my ever-so-helpful cats had moved my code folder to another location.

All is now well. And I'm creating a new backup.

Beer Batter Is Better

Why beer batter makes scientifically superior fish and chips.

Beer is saturated with CO2. Unlike most solids, like salt and sugar, which dissolve better in hot liquids than they do in cold, gases dissolve more readily at low temperatures. Put beer into a batter mix, and when the batter hits the hot oil, the solubility of the CO2 plummets, and bubbles froth up, expanding the batter mix and lending it a lacy, crisp texture.

Read the whole tasty article at Scientific American.