NEW YORK (TheStreet) -- St. Patrick's Day success in the beer industry is measured in quantity, but it takes a substantial investment in quality to get that perfect holiday pint.

Brewers went into last St. Patrick's Day in no mood to celebrate after U.S. beer shipments fell 2.3% in 2009, according to Beer Marketer's Insights. Judging by Brewers Association figures for last year, brewers' luck -- Irish and otherwise -- didn't change much when the holiday arrived amid a 2.7% slump in first-half sales. That didn't stop Diageo's ( DEO) Guinness from selling 3.5 million pints last March 17, an increase from 2009 and well above the 600,000 pints Guinness representatives say Americans drink every other day of the year.

Beers such as Samuel Adams and Guinness have extensive quality control systems in place. Consumers can send back Sam Adams that's past its freshness date for a full refund from brewers and distributors.

With all imported beer experiencing a 10% sales slump in 2009 and Diageo Guinness itself seeing a 10.3% decline that year, why did Guinness fare so well last St. Patrick's Day? Diageo Guinness USA Director of Quality Tim Cowlishaw says the credit belongs not to a Dublin brewery's worth of Irish heritage and association with all things St. Pat's, but with a legacy of quality control that pours a little bit of marketing into a whole pint full of nitpicking.

"The Diageo business celebrates big-time in the run-up to the holidays in December and we on the Diageo Guinness side see a huge increase in the setup of accounts to make sure they're looking as St. Patrick would like them or Arthur Guinness would like them," Cowlishaw says. "We see a substantial increase in the bar owners' request for support and help, and obviously we want to showcase our brand as well as possible."

That sweet display of Guinness' signature stout doesn't come cheap. In addition to Cowlishaw, Diageo-Guinness' U.S. operation employs four regional quality control coordinators, 100 salespeople steeped in the Guinness' multistep quality testing and more than 300 distributors throughout the U.S. who attempt to ensure that every pint of Guinness poured looks exactly like the black, foamy, ring-leaving pints the company idealizes and its sellers count on. Like a Smirnoff Ice or Twisted Tea sold in the summer, a Guinness sold on St. Patrick's day is making a first impression and trying to bring the consumer back for more

"We live or die by St. Patrick's Day with Guinness," says Mike Braccia, spokesman for Burke Distributing in Randolph, Mass., which handles Guinness distribution for 2,900 bars and other clients in Greater Boston and makes 15.5% of its annual Guinness sales on St. Patrick's Day. "That's why we strive to make it as perfect as we possibly can -- because you have one shot to make it."

Colishaw's St. Patrick's Day push starts in late January and early February, when the first of his team members begin surveying pubs and ordering pints. They check if bartenders are dispensing Guinness in two-step pours: a three-quarter first pour followed by a cooling-off period that allows the beer's bubbles to "surge and settle" and a second pour to ensure a head that rests just above the top of the glass.

Beer drinkers wondering what's taking that Guinness so long should be aware that Diageo Guinness believes the pouring process should take 119 and a half seconds. Cowlishaw, meanwhile, is counting every second of every pour through his team's Guinness' 24-7 mobile update system.

"I get a little reminder whenever somebody is serving a pint, wherever in the country, no matter what time of day or night," Cowlishaw says. "My BlackBerry is usually too hot to touch in the month of March."

His team's next step is the glassware, where they polish their sales chops by trying to get bars to take Guinness' preferred 20-ounce "tulip glass" but settling for "beer clean" glasses that don't have leftover soap residue and allow the beer to form rings down the glass as patrons drink. That's no small feat in Boston, where Burke Distributing's hundreds of bar clients make it tough to keep tabs on every establishment.

"It's a really dense territory for bars, so it's a pretty big challenge in the city to make sure the bars are up to par," Braccia says. "We almost doublecheck on the people that service their line or dishwashing liquid because they'll tell them to add more soap, and we're telling them to use less -- because you don't want anything that'll keep the glass from being beer clean."

After checking lines, hoses and taps for buildup, his team takes the beer's temperature. A healthy Guinness moves the mercury to between 38 and 43 degrees, though Colishaw reluctantly lets some bars drop a few ticks cooler "because of their consumer base." The final step is managing the taps' gas and pressure by making sure the force pumping the beer through the taps is made up of 25% carbon dioxide and 75% nitrogen, giving Guinness its creamy texture and foamy head.

Why would any self-respecting bar make its staff jump through this tedious series of hoops? Money, and lots of it. According to Cowlishaw, bars that run his gantlet see a 10% to 25% sales lift over neighboring pubs that don't.

"The research we've done shows that if they actually get it right, consumers have said we're going to stay longer, we're going to spend more money in that place, we're going to go back there more often and tell our friends that pub really sells a great pint," Cowlishaw says. "It can be a real business winner for the retailer."

Though Guinness' history of quality control goes back to 1908 -- when Guinness biochemist William Sealy Gosset developed the first "t-test" statistical formula that allowed researchers to use small samples to test large batches, giving birth to modern quality control -- it's far from the only brewer using such measures for free marketing. Boston Beer's ( SAM) Samuel Adams brand allows consumers to send back beer that's past its freshness date to brewers and distributors for a full refund, and they buy back roughly $1 million worth of beer each year.

Taking a page from Guinness, Samuel Adams released its own custom pint glass in 2007 and recently began a "Perfect Pour" program that includes "holding waitstaff training sessions, demonstrating how to pour the perfect pint and ensuring that the beer is fresh and the draft lines are clean," according to the company. While Boston Beer's shipments increased 1.5% in 2009 and 19% during the St. Pat's-laden first quarter of last year -- bringing in 16% more green in the process -- a little extra luck never hurt.

Not to be outdone, Diageo last week updated its Guinness Pub Finder map to let Apple ( AAPL) iPhone users rate their pints of Guinness and critique the pubs they came from. Colishaw says this has given him 50 new amateur quality control experts a day for the last week.

This doesn't mean that there won't be Guinness with flat head served in generic pints or even plastic cups this St. Patrick's Day, or that the harried bartender pouring Sam Adams Irish Red Ale for the first time won't give elbow-to-elbow crowds more foam than they'd like. If each company gets their way, savvy consumers just won't be drinking in those establishments.

"For sure, two days before St. Pat's you're not going to convince a retailer to take in a Guinness glass instead of that ubiquitous 16-ounce shaker that doesn't do anything for a great pint of Guinness," Colishaw says. "We're not going to win those conversations 48 hours before the big event, but we can drive the visibility of the pubs and other accounts that serve a great pint and are the places that people gravitate to."

-- Written by Jason Notte in Boston.

>To contact the writer of this article, click here: Jason Notte.

>To follow the writer on Twitter, go to http://twitter.com/notteham.

>To submit a news tip, send an email to: tips@thestreet.com.

RELATED STORIES:



Jason Notte is a reporter for TheStreet.com. His writing has appeared in The New York Times, The Huffington Post, Esquire.com, Time Out New York, the Boston Herald, The Boston Phoenix, Metro newspaper and the Colorado Springs Independent.

More from Food & Drink

Is This the Summer of Spiked Seltzer?

Is This the Summer of Spiked Seltzer?

This Could Be the Summer of Hard Seltzer

This Could Be the Summer of Hard Seltzer

Why Chipotle Is Headed to $450 a Share

Why Chipotle Is Headed to $450 a Share

Dunkin' Donuts Should Just Sell Itself Already

Dunkin' Donuts Should Just Sell Itself Already

Burger King Issues Apology After Massive World Cup Promotional Fail

Burger King Issues Apology After Massive World Cup Promotional Fail