Kosmic Mother Funk (KMF) Grand Cru
Boston Beer Company (Samuel Adams)

Kosmic Mother Funk (KMF) Grand CruKosmic Mother Funk (KMF) Grand Cru
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Wild Ale
Ranked #753
Ranked #5,574
4.07 | pDev: 10.07%
Boston Beer Company (Samuel Adams)
Massachusetts, United States
Kosmic Mother Funk (KMF) Grand CruKosmic Mother Funk (KMF) Grand Cru
Notes: Kosmic Mother Funk is a one-of-a-kind Belgian ale fermented with multiple micro-organisms including Brettanomyces, Lactobacillus and other wild critters found in the environment of our 150 year old brewery. KMF is aged in large oak barrels which impart unique flavors into the KMF as it develops its flavors for over a year. Wild yeast and different bacteria in the tuns impart unique spicy, fruity, and bright tart characters to the beer. The porous character of the oak also allows air to slowly seep into the beer during aging and this long slow micro-oxidation through the wood smooths out harsh flavors.

KMF is the backbone of all of our Barrel Room Collection beers and is blended, at varying amounts, into each of the five Belgian inspired brews that make up this collection. Its wild, funky character creates a new depth and spectrum of complex flavors from earthy and spicy to floral and sweet.

To showcase the unique character of this brew, we’re introducing Kosmic Mother Funk Grand Cru this year for the first time. On its own, KMF is tart, funky, and complex with notes of dark fruits, cherry, cocoa & vanilla. To bring together these flavors we’ve added a small amount of Belgian candi sugar to add a bit of smoothness and hint of sweetness to this vintage.
Reviews: 23 | Ratings: 195 | Log in to view all ratings and sort
Photo of CrackPo7
CrackPo7 from Virginia

3.46/5  rDev -15%
look: 3.75 | smell: 3.25 | taste: 3.5 | feel: 3.5 | overall: 3.5

Tart. Vinegar finish that blends into tart cherry. Hint of chocolate. Very light sweetness and vanilla that is difficult to detect. Not very frothy. Seems light for a dark colored beer.

May 26, 2019
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Riff from Virginia

3.96/5  rDev -2.7%
look: 4.25 | smell: 3.75 | taste: 4 | feel: 4 | overall: 4

Pours a dark reddish brown with no head. Smell is tart cherry. Taste is a tart chocolate cherry. Medium body, some carbonation. It's nice to have once, not sure I would get it again but good to try.

May 26, 2019
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brentk56 from North Carolina

4.24/5  rDev +4.2%
look: 4 | smell: 4.25 | taste: 4.25 | feel: 4.25 | overall: 4.25

Appearance: Pours a tawny, almost fudge color; relatively clear with a modest cap; a few shards of lacing

Smell: Lactic tones of cherry and blackberry with toffee and cocoa tones buttressing

Taste: Lactic sour tones of cherry and blackberry combine with toffee, cocoa and a hint of caramel; oaky, through the middle, with a vinous red wine character developing; a hint of vanilla emerges with the oak in the finish

Mouthfeel: Medium to full body with moderate carbonation

Overall: I wish we saw more beers like this from Sam Adams on the shelves but I guess the logistics around production and distribution make it a challenge for a larger brewery that is not focused on serving this end of the market

Dec 31, 2018
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gcamparone from Rhode Island

4.08/5  rDev +0.2%
look: 4.25 | smell: 4.25 | taste: 4 | feel: 4 | overall: 4

Pours a dark brown muddy body, very dark in the glass. Aromas of vinegar, dark fruits, toffee, caramel, tartness, funk. Taste is quite complex, tart vinegar, sweet toffee, vanilla, toffee, roasty. Interesting, easy drinker. Medium body.

Overall better than expected, reminds me of a flanders.

Sep 27, 2016
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metter98 from New York

4.14/5  rDev +1.7%
look: 3.75 | smell: 4 | taste: 4.25 | feel: 4 | overall: 4.25

On-tap at Mugs Alehouse, Brooklyn, NY

A: The beer is very dark reddish brown in color (but not black) when viewed from afar. It poured without any head on the surface.
S: Moderate aromas of sour cherries are present in the nose.
T: The taste follows the smell, having less sourness and additional notes of vanilla from the oak.
M: It feels light- to medium-bodied and a little tart and smooth on the palate with a moderate amount of carbonation.
O: This beer feels well rounded and mellow—it's not harsh like some other wild ales. The oak barrel aging really softens up the flavors.

Serving type: on-tap

Dec 05, 2015
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jzeilinger from Pennsylvania

4.16/5  rDev +2.2%
look: 3.75 | smell: 4 | taste: 4.25 | feel: 4.25 | overall: 4.25

A - Pours a very deep burgundy color with minimal lacing and carbonation.

S - Sour cherries, oak, tartness, with some funkiness.

T - Tart and sour cherries, mild funkiness going on, cherry skins, mild vanilla. Nice lingering cherry funky tartness.

M - Medium body, medium dry finish on top of the tongue while the tartness makes the sides of the tongue salivate.

O - This Cru is nicely done and the tartness is tame compared to some others out there.

Oct 04, 2015
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Roguer from Georgia

4.2/5  rDev +3.2%
look: 3.75 | smell: 4.25 | taste: 4.25 | feel: 4 | overall: 4.25

Extremely dark and thin appearing brew, like a BSDA. Minimal head.

Immediate Brett funk on the nose, but it's blended with an unmistakable sour edge, not unlike that found in Flanders red ales.

Flavor follows: it's immediately sour up front (again like a Flanders), but balanced against toasty, grainy malts and a very rustic funk from the Brett. Excellent balance of complex flavors. Delicate brew.

Sep 19, 2015
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cjgiant from District of Columbia

4.08/5  rDev +0.2%
look: 3.75 | smell: 3.75 | taste: 4.25 | feel: 4.5 | overall: 4

On tap:
Pours a very dark burgundy/brown - the former based on light from the edge of the beer. The pour had a half centimeter of head, but within a minute of sitting in front of me, there was barely a few bubbles at the edge. Clarity is probably high as I get a shadow effect when I throw my hand behind the beer.

Nose is subdued tartness and seems vaguely Flemish sour in nature. A little oakiness and a hint of dark fruit. The smell indicates there could be a little sour apple or sour cherry in the taste, but that's an impression. A warmer beer yields a hint of brown sugar.

A very subtle sour, but an enjoyable one. It is actually hard to distinguish what flavor is generating the sour note, but it is there. It almost seems like an extra tart, perhaps unripe fruit - like a sour grape or tart raisin. There is a nice sweetness countering the sour notes, canceling them but losing out in the end. This countering taste is dark sugary in nature but far from cloying, maybe cola-ish.

Feel is actually commendable. Obvious and enhancing carbonation is decently strong without attacking the palate. Or it could be the combination with the tart notes that yield a pleasant tingle in the tongue.

Without being exciting or complex, this was a very enjoyable beer. It also wasn't pedestrian and boring. More mellow than many craft wild ales, but typically Sam - well made.

Sep 17, 2015
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jwc215 from Arizona

3.83/5  rDev -5.9%
look: 3.75 | smell: 3.75 | taste: 3.75 | feel: 4 | overall: 4

On-tap at Three Cellars, Franklin, WI:

Pours brown with a thin head. A wide island lasts and leaves some trailing lace.

The smell is of sour cherries, vanilla and brown sugar.

The taste is sour with wet wood. Cherries, vanilla, a hint of cocoa comes through. Some candy sugar gives it a sweet balance in the finish, but some of the "funk" sour stays.

It is smooth.

A pleasant, unique "wild ale". Certainly not the funkiest, but enough to fit. A candy sweetness gives it balance and adds to smoothness and ease in drinking it. An enjoyable brew.

Sep 16, 2015
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tigg924 from Massachusetts

3.74/5  rDev -8.1%
look: 3.75 | smell: 4 | taste: 3.75 | feel: 3.5 | overall: 3.5

Had on tap at Flynn's Cedarville. Wow is this sour. Pours clear, dark brown with 1/2 head and moderate carbonation. Taste is plum, dark cherry, light wood, and tons of sour mix. Very tasty but truly a sipper. Glad I had a chance to try it, but I do prefer others in the style.

Aug 20, 2015
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BeerAndGasMasks from Virginia

4.04/5  rDev -0.7%
look: 4 | smell: 3.75 | taste: 4.25 | feel: 4 | overall: 4

Poured a dark ruby into the glass with a small head that dissipates rapidly as poured from a growler. Sourish smell and striking sour taste. Delish!

Jun 30, 2015
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Stinkypuss from Pennsylvania

4.31/5  rDev +5.9%
look: 4.25 | smell: 4.5 | taste: 4.25 | feel: 4.25 | overall: 4.25

LOOK: Very deep ruby red. Close to amber/brown in a large, non stemmed glass. Nice clarity and excellent overall look.

SMELL: Wine like sour aroma carrying berries and cherry, though I believe this ale is unfruited. Complex intoxicating aroma broadly in the flemish oud bruin style.

TASTE: A nice sourness going on, lacto seems heavy, cherry is unmistakable from the yeasts wow. Very nice tasting brew that is ample sour but not over the top. The oak used in the barrels was actually imported and the aging vessels built on premise in Boston Beer Co. which is cool. Bolivian oak if I am not mistaken, which gives the barrels a light vanilla flavor though the oak never held any liquid before this beer. Still acetic notes of red wine vinegar are much stronger. Complex with sour and malt notes and a hint of slight vanilla and char in the finish.

FEEL: Full bodied, yet still lively and not heavy on the tongue. The bubbles carried the flavor well throughout the brew. Really nice, meant to be sipped and savoured.

OVERALL: A solid sour beer with large strength and good depth of flavor. I can see why this is a choice blending agent for the Stoney Brook Red and the barrel room series. That being said this is much better than those and a beautiful beer straight up. Imagine a Rodenbach with a slightly more toasty malt flavor and an ever so subtle hint of vanilla. Drinkable for an extreme beer.

Jun 08, 2015
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vfgccp from New York

4.68/5  rDev +15%
look: 4.5 | smell: 4.5 | taste: 4.75 | feel: 4.75 | overall: 4.75

I am fortunate to have enjoyed this twice now, most recently at Savor 2015 in DC, and I have been absolutely stunned by it both times. The quality, complexity, and balance of the beer's flavor profile is simply fantastic.

Jun 07, 2015
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HattedClassic from Virginia

4.18/5  rDev +2.7%
look: 4.25 | smell: 4.25 | taste: 4.25 | feel: 4 | overall: 4

Growler in a Wicked Weed Red Angel glass.

The beer pours a nice off white and slightly reddish head that dissipates very quickly. The beer itself is an opaque burgundy color. To better describe, the color is similar to a ripe plum. The beer also has a slight wine texture to it as well.

The beer smell has a very strong tart/sour note. In other words, the beer has a very strong funk to it. However, the funk isn't the only note even though it overpowers some of the other notes there. The beer also has a nice dark fruit and malt note that sometimes comes through. Once you get past the strong funk, dark fruit notes such as plum and a bit of dark cherry penetrate the nose. If only the funk wasn't as strong, the smell would fantastic instead of just good.

The beer taste is very interesting and better developed than the smell. The taste seems to have both a sweet and sour side. The sour side is obviously comprised of the yeast used to create the sour/tart notes. The sweet side is mainly comprised of dark fruit notes such as plum and figs. The dark cherry note found in the smell does not seem to be as dominate here but still make an appearance.

The mouthfeel is pretty heavy. The beer is definitely medium bodied with some biting carbonation. The beer has some viscosity to it but it adds rather than detracts from the beer,

Overall, a very good from Boston Beer Co. and worth getting on your hands if you can. The sour note is just right for a beer of this kind. The trick is drinking at the right temperature so that you get all the notes instead of only the funk.

May 18, 2015
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GreesyFizeek from New York

4.21/5  rDev +3.4%
look: 4 | smell: 4.25 | taste: 4.25 | feel: 4 | overall: 4.25

On tap at EBF in Boston, MA.

This one pours kind of a reddish brown, with no head or lacing.

Smells really quite nice- some cherries, damp wood, slight vinegar, red wine, a bit of chocolate, and lots of kosmic funk, clearly.

This is a really nice funky and moderately tart sour. Lots of juicy tart cherry, plum, and a little bit of blackberry, maybe, with some vanilla, a bit of chocolate, some oak/damp wood, and just a splash of lactic acid and vinegar. Really well-balanced, and surprisingly complex and daring for Sam Adams.

This one has a light body, with a juicy mouthfeel, and a moderate level of carbonation. It's quite drinkable.

This is a really impressive beer. It should get higher marks.

Mar 23, 2015
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StonedTrippin from Colorado

4.26/5  rDev +4.7%
look: 4 | smell: 4.25 | taste: 4.25 | feel: 4 | overall: 4.5

no denying what the other reviewers have said here, this is downright fantastic beer, and while sam certainly isnt known for these kinds of wild beers, this is just awesome, and one of their best. its a burgundy color, oud bruin-esque, with a short cream colored head. the nose is as funky as it is sour, less lactic acidity, more woody must, with a sturdy malt base that has a lot of dark fruit notes and a tingle of sweetness before the acid comes in. its layered and complex and not like other wild ales on the market, especially in feel, where its solid carbonation meets medium body and sweet and sour both on the tongue, very cool. i get cherry and oak, red winey in what way, dark sugars, and wild yeasts with a fair amount of time to develop. i dont believe they package this one, but wow they really should. all these articles about these guys getting left behind by the craft movement and all, this might be a good way to win them back if that is in fact the case. unique and delicious, unlike others thats for sure.

Jan 15, 2015
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LambicPentameter from Nebraska

4.31/5  rDev +5.9%
look: 4 | smell: 4.25 | taste: 4.5 | feel: 4 | overall: 4.25

Was lucky enough to enjoy this beer that rarely makes it out of Boston when they did a "world" tour this past fall/winter. Kansas City's growing beer scene banded together and voted ourselves in to the tour as the final fan-voted stop. Enjoyed at Bier Station as part of the tour stop kickoff. Poured into a large Belgian-style tulip glass.

Appearance (4.0) - Nothing particularly mind-blowing to start. A dark, ruddy bistre brown hue that is dark enough that I can't really tell if it's hazy or not. Atop the body lies a lazy half finger of ecru foam that dissipates pretty quickly, leaving no trace that it ever existed at all--no film, no lacing, nothing.

Smell (4.25) - First whiff gives off a nice blend of complementary notes, with some medium and dark fruit along the lines of black cherry, date and red plum, but the undertone supporting all of it is a vein of balsamic acidity and a slight pinch of tartness. The aroma suggests that what I'm about to taste will have a sweet and sour characteristic.

Taste (4.5) - The nose did not let me down, giving quite a good approximation of what was in store for me. The same fruity sweetness is here, with black cherry and plum leading the way, with perhaps some hints of black currant that I didn't get much of from the aroma. However, the tartness is much more present, providing an even balance of balsamic vinegar to cut the sweetness and push this beer into entirely unique territory. I'm not joking when I say that I'd be slightly curious to mix this with some olive oil and dip some some French bread into it. The taste also reveals a vinous character that I didn't explicitly detect in the smell, with notes of red wine and oak.

Mouthfeel (4.0) - Medium-bodied and low carbonation, with a slightly slick, coating feel on the tonuge and a slight pinch of tartness on the tastebuds. Semi-sweet finish.

Overall (4.25), this is probably my favorite Sam Adams beer to date. I've never had the opportunity to try any of the Barrel Room Series beers that all use KMF as a base to varying degrees, but trying this one on its own has certainly piqued my curiosity. It drinks like a unique twist on a Flanders Oud Bruin and I would love to have some more.

Jan 07, 2015
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NeroFiddled from Pennsylvania

4.5/5  rDev +10.6%

Samuel Adams Kosmic Mother Funk
On tap @ Pinocchio's Restaurant, Media, PA

I was starting to worry that Boston Beer wasn't keeping up with the changes in the beer world these days, thinking that maybe they'd fall behind because people have tired of their regular beers, and even their seasonal offerings, but this changes everything!!! WHAT A BRILLIANT BEER! It's got a lot of funkiness to it. It's got lactobacillus, it's got Brettanomyces, and it's got a bit of swagger to it as well, yet it's all tightly wrapped up in a clean, focused, and still malty package. It's sour/sweet with lots of red fruit, dark skinned fruit, and wet leather. Remarkably drinkable, interesting, and complex.

Dec 06, 2014
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Flounder57 from Massachusetts

3.78/5  rDev -7.1%
look: 4.25 | smell: 3.75 | taste: 3.75 | feel: 3.75 | overall: 3.75

Served in a goblet at the Union Brewhouse in Weymouth.

Appearance: A one finger off white head was poured that reduced to a thin layer. It is an amber brown color with no vision of anything. Spotty lacing down the glass as the beer was drank.

Smell: Funky, hay, bready, cherries or raspberries , rubber tires, and some sweetness.

Taste: Very funky and tart, some fruit sweetness, bready, and more funk.

Mouthfeel: Tart, bready, funky, Medium bodied, a little dry, and medium to high carbonation.

Overall: Nice stuff, but a bit more funkier than one would like. A little more sweetness would be good, but it did get better as it warmed up.

Dec 04, 2014
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1000lbgrizzly from Illinois

3.73/5  rDev -8.4%
look: 3.75 | smell: 3.75 | taste: 3.75 | feel: 3.5 | overall: 3.75

A: Clear, very dark brown with ruby tint. Loose ample carbonation, light tan velvety, lathered-soap head that gradually dissipates to a collar and weak remnants in the center. Webs and dots of lace. Bottommost layer is reminiscent of intestinal celia.

S: Some sourness, cherry, a very faint yeast/bacterial funk.

T: Semi-sour cherry, mid-palate sweetness, as if simple syrup were added. A sheet of yeast funk is present throughout, but minor. Decent finish, semi-sharp acidity.

M: Lightly prickly, smooth-ish. Lighter bodied.

O: Not weak, but could be more in-your-face. Definitely not worthy of the 'Funk' in the name; it would have been nice to see bolder sour and funk side-by-side. It doesn't commit to any vector enough to make it an outstanding sour or funky beer, but nevertheless a very good and repeatable brew with some original takes on the style.

Nov 18, 2014
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hayesjw from California

4.5/5  rDev +10.6%

A - Dark currant color with lacing on edges of a six ounce stemmed glass.

S - Sweet stone fruit present.

T - Late summer rippened plums with sour cherries or perfectly unrippened strawberries maturated in old Burgundy barrels.

O - This draft pour is affordably priced at the 547 for five dollars. My first introduction to this wild ale was courtesy of the Flying Pig Bistro, San Francisco. Excellent overall and would hope Boston Beer Company would brew again with allotments to California. CHEERS!

Nov 16, 2014
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wisrarebeer from Wisconsin

4.25/5  rDev +4.4%

On tap at Rustico in Alexandria, VA. $9/glass. Overall very nice and highly drinkable. A bit cloying but very good for an American version. Could use a bit more tartness for my taste.

Nov 13, 2014
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buschbeer from Ohio

3.73/5  rDev -8.4%
look: 3.75 | smell: 3.75 | taste: 3.75 | feel: 3.5 | overall: 3.75

32 ounce growler
Served in a tulip glass

L - It pours dark brown in color. When held to the light it takes on a ruddy appearance. There is virtually no head. An aggressive pours yielded a few tan bubbles.

S - It has a strong tart smell. I get some vinous notes and a little apple cider vinegar.

T - The taste is very tart, almost mouth puckeringly sour. The wine and vinegar I smelled come through in the taste. It definitely leaves a sour taste in my mouth.

F - Moderate and very low carbonation.

O - A rare find. It was cool to taste a key additive to some of Sam Adams beers. One glass of this was plenty though. It has intense flavor, not all of it necessarily good.

Oct 25, 2014
Kosmic Mother Funk (KMF) Grand Cru from Boston Beer Company (Samuel Adams)
Beer rating: 91 out of 100 with 195 ratings