The last time Mystic Brewery released a beer from its Vinland series, it sort of wound up being the equivalent of a rookie hitting a grand slam on the first pitch of an at bat.

Last fall, after the Chelsea brewery submitted the beer to the Great American Beer Fest (GABF) – their first submission ever, mind you – it went on to win the gold medal in its category, ‘Indigenous Beer.’ That beer, Vinland Two, was brewed with a saccharomyces yeast strain harvested from Norridgewock, Maine blueberries.

Today, the brewery releases its latest in the series, Vinland Three, made with yeast cultivated from wild Vermont raspberries.

The series, which highlights beer brewed with local native yeasts, is an ongoing project for the brewery’s founder, fermenter, and skilled ‘microbe hunter’ Bryan Greenhagen. For this year’s version, Greenhagen harvested all of the wild fruit he could find and proceeded to go on a yeast treasure hunt of sorts.

“Yeast’s purpose on Earth is to eat fruit,” Greenhagen points out, “It’s usually concentrated on any fruit.” It was the yeast he found growing on raspberries at his grandparents’ farm in Popple Dungeon, a small farmstead in Chester, VT, however, that he ultimately wound up culturing in a mason jar.

For all intents and purposes, culturing yeast from fruit is not an easy task. Fruit can spoil, things can go wrong, etc. As Greenhagen wrote on the brewery’s blog yesterday, “natural fermentation isn’t something to just walk into.”

It helps that Greenhagen spent time as a Postdoctoral Fellow at M.I.T. studying fermentation and then several subsequent years as a scientist before he founded the brewery.

Being persistent doesn’t hurt either.

“We usually do at least 50 beers per culture,” Greenhagen said of the process, “Only one or two strains are any good.”

Once Greenhagen and company have narrowed down their options to a sample they like, they have to double-check and culture the yeast again. After they’ve nailed it down, they begin to do test batches with recipes and things get more challenging.

“The hard part is finding a recipe that works with the yeast flavor profile,” said Greenhagen.

After they found their raspberry yeast, something Greenhagen is nicknaming “Popple D” for now, they propagated a batch and pitched it normally during the brewing process.

From conception to completion the beer took about a year to develop.

The brewery calls an old industrial building home — not far from the river that shares its name – and has long been a purveyor of fine saisons (Mary of the Gael, Saison Renaud) and experimental barrel-aged beers (Entropy, Sauterneal). But the Vinland series is something else entirely.

As far as the GABF (See #18) is concerned, ‘indigenous beer’ is marked by  “combinations of ingredients and techniques adopted by or unique to a brewery’s particular region region.” With their native beers, Mystic is continuing to venture into uncharted territory that few breweries – save perhaps for Allagash in Portland – choose to experiment with, let alone devote their time and money to.

Vinland Three follows up Vinland Two, a 2013 beer brewed with yeast cultured from Maine lowbush blueberries and Vinland One, a beer Mystic brewed in 2012 with yeast cultured from a Massachusetts-grown plum.

It’s worth stressing that while Vinland Three is made with yeast harvested from the raspberries, the beer contains no actual berries.

“The only reason it’s raspberries is because a strain from a raspberry culture was the one we liked the best,” Greenhagen said, adding that they had to cycle through “many, many microbes” to find just the right culture.

It’s for that reason that beer drinkers shouldn’t expect Vinland Three to taste anything remotely like New Glarus’ Raspberry Tart or Founders’ Rubaeus, two other (very different) beers that feature the berry.

With that in mind we had to ask: What does it taste like?

According to Greenhagen, the beer has some pop to it and imparts a “mild tartness,” with notes of dark fruit, “a bit like a strange Belgian Dubbel.” While it’s not funky yet, it could be in time.

Four hundred cases or so of the beer were bottled, in both 750 mL and 375 mL vessels, and will be released at Mystic Brewery at 3 p.m. today. Can’t make it to Chelsea? The beer should see distribution throughout better beer stores in Vermont and Massachusetts in the very near future.

[Photo Credit: Mystic Brewery]