Fresh beer is the best beer.

Southampton—"I'm a stickler about authenticity," said Phil Markowski, darting back and forth between the brewing tanks and bar at the Southampton Publick House. He uses hops from the Czech Republic for recipes from that region, while favoring British hops for British beers. The crown moldings above his head are covered with red stencils of interlocking, botanically precise barley plants—one of the building blocks of beer.


At the only brewery east of the Shinnecock Canal, Mr. Markowski, master brewer since the Publick House opened in 1996, has produced a roster of distinctive beers that have as much history as flavor. As part of a nationwide craze for microbrews—America counts some 1300 breweries today compared with just 40 two decades ago—Mr. Markowski's style has built a reputation that stretches well beyond Long Island.


The pub typically offers 10 beers on tap, twice as many as most microbreweries, and many more from its cellar reserve of hand-bottled favorites. In addition to being served at discriminating New York bars and restaurants, Publick House brews also get high marks from international connoisseurs. The Abbot 12 and Cezanne captured medals at the Great American Beer Festival in October. Beeradvocate.com named the Publick House the number one brew pub in America last summer, and its beers are now carried in Philadelphia, New-Jersey and throughout New England. As of early November the pub has churned out a little over 2,327,996 pints. It hasn’t had a problem moving a single one, and customers are never quite the same.


"They can't drink Bud anymore,” Mr. Markowski said, wearing a navy blue Dickie's coverall and matching cap. "They have the revelation that beer can have complexity and flavor and you can drink a good amount of it and not blow up like a balloon." (Beer commercials that claim darker beers will weigh you down and make you fat are peddling myths, Mr. Markowski said.) 'Tell me what talking frogs have to do with. beer," he added, referring to the TV spots of companies like Budweiser and Anheuser Busch. 'They're not really selling flavor, their selling image.”


Instead, Mr. Markowski has drawn inspiration from the long history of brewing. Consider his "cask-conditioned" beer. Common in the United Kingdom, where it is sometimes called "real ale” or simply "cask," this is a throwback to the days before pressurized carbon-dioxide kegs when beers were stored in the back of the pub and hand pumped into glasses. It’s not filtered, not chilled, and not carbonated, although the live yeast gives it a bit of fizz. “It’s not as rough on the mouth, and there’s no carbonation to distract from the taste,” Mr. Markowski explained.


For a recent Slow Food dinner at the American Hotel, Markowski dug deep into his historical cookbook to replicate an Alsatian farmhouse brew called March Beer. It was typically made in the fall from the newly harvested crops and, before artificial refrigeration, it could age slowly over the winter, developing a smoothness that was unusually and quite a treat when served in the early spring. (It was also an early form of marketing that primed people for the new beer season, said Mr. Markowski, who recently published a book on farmhouse ales.)


The best way to get a sense for these subtleties is to order the Publick House’s “Sampler,” a diagrammed platter holding 10 shot glasses full of beer that range in color from near espresso to lemonade to caramel. "It was a conscious effort to have a wide range of colors,” Mr Markowski said. “No matter how open-minded someone is, the first thing they look at is color." (The ale-battered onion rings provide a natural tasting partner on a cold winter's day.)


The sampler includes the four brews that are always available: Montauk Light (the most popular selection, which emulates the typical American light beer, but “has more flavor,” Mr. Markowski said), Southampton Golden Lager (a Munich-style lager and one of the earliest light beers), the Southampton IPA (a fruity and bready English-style amber made with a blend of five hops), and the Secret Ale (a copper-brown, refreshingly bitter altbier from Dusseldorf, Germany, which was a stubborn holdout- against the more modern lagers, and "another little known obscure style"). Among the pub's other seasonal beers are the Publick House Porter (a London-style ale with notes of chocolate, toffee and caramel), the Southampron .Saison (a dry Belgian farmhouse ale), a Bavarian wheat beer (a southern German recipe whose particular strain of yeast yields banana, clove, nutmeg, vanilla, and lychee flavors), and the Burton Ale (Mr. Markowski adds salts to the brewing water to simulate the high mineral content of Britain’s famous Burton-on-Trent beers, and described the flavor as "sulfury in a pleasant sense as you sometimes get in wine").


All of this from a self-trained brewer who first tried his hand at beer-making in 1984. "Summer was over by the time I had my first batch,' he said. He read up, joined some brew clubs, experimented with different recipes, and learned how to balance the two ingredients that give beer its flavor: hops for bitterness and malt for sweetness. "At this point, I. make them up off the top of my head," he said, and then shifted to a more serious express. “I keep very careful records.”


Today, he brews beer several times a week, and the best way to learn about the process is to simply visit: the Publick House. In one corner of the restaurant, behind floor-to-ceiling glass panels, patrons can see the fermenting tanks, boilers, and knots of shining metal tubes unfold like something out of Charlie and the Chocolate Factory. Color-coded arrows and numbered signs explain how it all works.


Even with its formidable pedigree, the Pubiick House remains a decidedly locals joint. Contractors, landscapers, fishers, teachers, and bank clerks filter in after work with cellphones pinned to ears. As many at the bar are wearing camouflage as Polo. “Howaya?,” is the common retrain between bartender and patron. The television flips between ESPN 1's coverage of the world's strongest, man competition and basketball highlights on ESPN 2.


A chalkboard includes more information than the typical beer drinker needs—or probably wants—to know. It lists the alcohol content, flavors, scents, and brewing technique for the pub's offerings. To remind patrons that all the beer is made on site, a sign reads
"Fresh Beer is the Best Beer." Anything on tap at the brewery is, at most, weeks old, in contrast to months or more for most imported beers. 'It's not like wine,' Mr. Markowski said. “It’s a fragile product that needs to be consumed fresh.”


Despite his allegiance to tradition, Mr. Markowski doesn't pass judgment on beer drinkers, just their prejudices. "If someone does it strictly out of close-mindedness, then I think that’s too bad," he said about people who shy away from trying new beers, "I certainly don't feel any disdain."


And Mr. Markowski isn't shy about trumpeting the significance of beer, one of humanity's oldest prepared foods. "There is evidence of beer recipes back to 3000 BC,” Mr. Markowski said. "Anthropologists have argued that the motivation of human tribes to first grow barley was for making beer." The first beer probably resulted when a proto-brewer mistakenly left bread or gruel out in the rain, which was colonized by yeast in the air, began to ferment, and looked and smelled interesting enough for some brave soul to taste.


Ever since, beer has played an important, if underrated, role in human history. “Supposedly, on the Mayflower, their provision of beer had run out," Mr. Markowski noted, "and this was one of the motivations for landing at Plymouth Rock instead of St. Augustine." In sanitation-deprived medieval and colonial times, drinks like beer were safer than water. Until the last century, it wasn’t unusual for people to drink beer all day. Both George Washington and Thomas Jefferson were big beer drinkers. ("That’s a. bit of beer lore." Mr. Markowski said.) And, because shipping kegs was expensive and impractical, every town had its own breweries, and most inns and restaurants brewed their own. (The Publick House was originally an inn.)


The time when every small town--on the East End or elsewhere—will again have its own brewery might still be decades in the future. But Mr. Markowski is optimistic. "Every beer I had as a kid came from somewhere else," he noted, "Milwaukee or St. Louis." There are now four breweries on Long Island alone, and since the public has tasted the difference between crafted beers and industrial brew, Mr. Markowski is confident that no one will have to again settle for anything but microbrew. "It’s here to stay.”