Local secrets to cold brewed coffee

Occasionally, when Ben Lee hands over his stylishly labeled dark bottles of Northern Bayou Cold Brew to customers at the Burlington farmers market they step away only to return with a puzzled look.

They think they've purchased beer, when in fact they've purchased chilled coffee concentrate.

Lee, 28, spends quite a bit of time at market each week explaining his product, even though general awareness of cold-brewed coffee has climbed in Vermont over the last few years.

"Rather than brewing for two minutes at 200 degrees, you do a 12 to 24-hour brew at a much lower temperature," he explained on a recent market day. "The process extracts less acidity so it's smoother than a hot-brewed coffee. It comes out as a concentrate so you can dilute it with water or milk."

Cold brew can be served chilled over ice or diluted with hot water, but it tends to be used more as a base for iced coffee, especially in the heat of summer.

At Northern Bayou's farmers market stand, Lee sells bottles of his original concentrate as well as one brewed with hops (it contains no alcohol but might further excuse those who mistakenly believe they're purchasing beer) and another with cacao nibs.

Adding more room for confusion, he also offers his original on tap poured over ice and even a tap version with an infusion of nitrogen, called "nitro cold brew," which results in a cup with a creamy froth on top reminiscent of the head on a Guinness stout, or the crema of an espresso.

Spreading the cold brew

Although cold brew has been around since the 1960s when a Cornell-trained engineer named Todd Simpson developed a cold brew system called the Toddy, it has become more high-profile over the last decade or so.

Lee, who grew up in Williston, was introduced to cold brew coffee while in college in Boston. He was drinking about 80 ounces of coffee a day and feeling the effects of all the acid, he said, until he switched to his own Toddy-made cold brew.

It wasn't until he moved to Brooklyn that Lee began dreaming about starting his own cold brew business after he had refined his method with lots of experimentation.

"I'd always been thinking I might do something entrepreneurial," he said, "but in Brooklyn, we were a little late to the game. There were already four companies bottling cold brew. My wife and I had decided to move back here away from the grind of the city and in 2012 when we did, no one in Vermont was doing it."

He launched Northern Bayou in the fall of 2014, brewing freshly roasted beans sourced from Vermont Artisan Coffee of Waterbury and Brio Coffeeworks in Burlington in a commercial kitchen space in Charlotte. He is also brewing special batches with beans from the new Carrier Roasting Co. of Randolph.

There are a variety of different cold brew methods and Lee declined to share specific details of his other than to say he uses custom equipment and triple-filters the concentrate to remove oils and sediment.

Other local collaborations include sourcing some Vermont-grown hops for the hopped cold brew and cacao nibs from Blue Bandana Chocolate on Pine Street for the cacao cold brew. He also does some custom cold-brewing for Brio.

14th Star Brewing in St. Albans is using Northern Bayou coffee in their maple breakfast stout and the hopped coffee was inspired by a conversation at Growler Garage in South Burlington where Lee's wife Amanda also works.

In addition to direct sales at the farmers market, Northern Bayou also sells to City Market, Burlington Beer Company, Growler Garage and Winooski's Beverage Warehouse. Lee is hoping to do more events and catering.

"Different tastes"

Cold brew may have the buzz going for it, but it is only one of several ways experts make iced coffee.

"Never say one way is the best way," says Don Holly, who has worked in specialty coffee for more than 30 years including a dozen at Green Mountain Coffee Roasters (before it was Keurig Green Mountain) and more than five running the Specialty Coffee Association of America. "Everyone has different tastes."

Holly's personal preference is custom-brewed espresso immediately poured over ice. He likes his with 1/2 teaspoon maple or honey stirred in and nonfat milk to dilute it.

At the Bristol Bakery and Café location in Hinesburg recently, he popped behind their espresso machine to demonstrate.

He had brought his own tamper to firmly compress the freshly ground coffee in the machine's basket. "The tamper is kind of like the samurai sword for the barista," he confided. He brewed the shot for precisely 28 seconds, showed off its perfect crema and poured the inky dark liquid straight into a cup of ice.

Coffee made to be served iced will normally be concentrated so it doesn't become weak when the ice melts, Holly said; espresso will be the strongest of all brewing methods.

Regular brewed hot coffee is usually about a 1 percent ratio of coffee to water; Starbucks made a name for itself by brewing at a 1 1/2 percent ratio, he said. A well-made shot of espresso, he continued, is about 12 percent and can even reach 20 percent. In contrast, concentrate from the cold brew Toddy method is about 5 percent.

Extraction variables

Brewing is an extraction process, Holly continued, that pulls soluble materials out of insoluble material. Only 30 percent of roasted coffee is soluble materials—about 2,000 different ones, he said. The rest is cellulose.

"But not all of that soluble material tastes good," he continued. "The goal is to pull out only the good stuff. Different chemicals come at out different times and in different ways. Nature was nice to us and made the good stuff come out first."

How you extract, or brew, will naturally impact the resulting coffee.

For iced coffee, additional variables include the type of beans, roast, grind, water and ratio of concentrate to water, ice or other liquid.

"Your tools for brewing are time, temperature and turbulence," said Holly, and the more of each of these, the higher extraction you get, he explained.

Turbulence, he specified, includes agitation and pressure. On the low end of turbulence is steeping (the most basic cold brew method) and at the high end is the pressure exerted by an espresso machine.

Although Holly said that cold brew does not yet have an official definition, it essentially means that the coffee is brewed without hot water, although there are various ways the cold water can travel through the grounds.

No matter how it travels, one thing cold water does not do is dissolve fat like hot water does. This results in less aromas and what he described as a "softer" flavor profile.

In contrast, Holly explained, "espresso emulsifies the oils and proteins and produces the crema and all that aroma."

"Any time something is hot, the aromatic molecules are more volatile," he said, using the example of cold pizza versus hot pizza.

One thing that cold brew will have more of, however, is caffeine, thanks to the longer extraction.

Between the complete caffeine extraction and the higher concentration of the coffee solution, Holly explained, "Cold brew drinkers are all of a sudden dancing on the ceiling."

Shock it

At Scout and Company's two locations in Winooski and Burlington's Old North End, they use a different method to make what they consider to be optimal iced coffee.

"We haven't found a cold brew method that lives up to our taste expectations," explained co-owner Tom Green.

"Coffee has a lot of terroir, like wine," he continued, referring to all the nuances of flavor and aroma that come from where and how coffee beans (and wine grapes) are grown. "We want to highlight all of those different flavors and we don't think cold brew maximizes those."

Scout and Company starts with a specific bean sourced and roasted by Brio Coffeeworks that they believe makes a great iced coffee: naturally processed Ethiopian Kochere from the Yirgacheffe region.

"It has a fresh clean taste," Green said, "with some citrus and cacao."

The iced coffee brewing style they use is sometimes called the "Japanese method." They brew the coffee double-strength through their regular hot coffee brewer but directly into a thermos filled with ice.

"So we're shocking it to preserve its flavor," Green said, somewhat like blanching vegetables in an ice bath after boiling them briefly.

Customers do still sometimes ask for cold brew, he said, with a shrug: "They are obsessed with it."

Debate

The two Bluebird Coffee Stops on Church Street and at the Innovation Center in Burlington's South End both serve cold brew iced coffee.

On Church Street, they advertise cold brew and pour from kegs bought from Brio Coffeeworks custom-brewed by Northern Bayou. (Brio also sells growlers of cold brew at their roastery and coffee equipment store.)

At the Innovation Center, lead barista Tyler Van Liew cold-brews the iced coffee concentrate usually with Brio beans, although the menu board does not specify that it is cold-brewed.

"I do like cold brew," said Jason Gonzalez, general manager of both Coffee Stops, who happens to be a two-time United Kingdom Coffee Cup Tasters champion. "Customers also sometimes ask for iced Americanos or espresso brewed over ice," he added.

"Hot coffee tends to oxidize and produce bitter flavors because the heat pulls more oils and tannins out," Gonzalez explained, "so it might taste more bitter when cooled."

In contrast, he said, "cold brew tends to produce a cup with lower acidity and lower bitterness."

"There is some debate," Gonzalez conceded, "that you may lose some of the aromas."

"And not every great coffee is great for cold brew," he added.

"Some people start the brew hot to bloom the flavors and then finish brewing with cold brew methods," Van Liew said.

When asked how he likes his iced coffee, Van Liew grinned and said, "I prefer hot coffee."

Contact Melissa Pasanen at mpasanen@aol.com and follow her on Twitter at www.twitter.com/TasteofVermont

How to make your own cold-brewed coffee at home using a French press

Tyler Van Liew and Jason Gonzalez of Bluebird Coffee Stop offered these tips on making your own cold brew at home. They note that you should experiment with different coffees and tweak the recipe to taste.

"Brewing is like cooking and every different coffee will brew differently. There is no set recipe for all coffees," Gonzalez explains.

Select a coffee you like. Coffees that are particularly fruity or floral, like many natural processed coffees, tend to make interesting cold drinks.

Grind it more coarsely than you normally would for hot-brewed coffee, about the texture of coarse sea salt.

Fill a French press with ground coffee and cold water at a ratio of 120 grams of coffee to a liter of water (weight is most precise), or 4 tablespoons coffee to 6 ounces of water.

Refrigerate for 18 to 20 hours and then slowly press down the plunger. Expect it to be more resistant than normal.

Pour over ice and add equal volume water for drip-coffee strength, or dilute to taste with your preferred milk.

To learn more:

Magda Van Dusen of Brio Coffeeworks has offered an iced coffee workshop in the past with City Market at Brio's Pine Street roastery and is currently planning another; exact details to be determined. Contact magda@briocoffeeworks.com for more information.