Experimental Coffee - Beer Yeast Fermentation

Experimental Coffee - Beer Yeast Fermentation

Fermentation is an integral point in the processing of coffee. For the majority of coffees, fermentation is a tool used to break down the sugary, gelatinous plant material (pectin) surrounding the coffee bean, once pulped. Specifically for washed coffees, it is not a means to enhance flavor or complexity but to remove the mucilage as quickly as possible before microbes are able to produce acids and esters that may be conceived as off flavors. 

Time is also extremely valuable to this equation as coffee fermentation typically  runs 12 to 24 hours, which is a very short compared to other processes like beer, cheese, wine, etc. Coffee is very malleable and porous after its pulped so too much time in the tank runs the risk of exposing it too much to all the microbial activity. With this experiment we wanted to use this to our advantage to allow the saison and ale yeast to produce compounds the coffee can absorb.

This process worked very similarly to the our hopped coffees, (Citra, Mosiac and El Dorado). These processes and can be considered a marinade for the coffee to sit in and absorb the wonderful flavors. These types of experimental fermentation are unique to Dark Matter Coffee and are part of our culinary approach to serving the best coffee in the world. 

If you need a little more help with understanding fermentation, read our previous blog post that helps to explain some of the fermentation and drying processes that are used. Also check out our other yeast experiments, using red wine and cuvee yeast on this blog post

Saison Yeast Fermented Coffee
Country: Guatemala 
Farm: San Jeronimo Miramar 
Cultivar: Catuai, Caturra 
Process: Fermented in Ale Yeast 
Notes: Cocoa Nibbs, Hazelnut, Currant

Country: Guatemala 
Farm: San Jeronimo Miramar 
Cultivar: Catuai, Caturra 
Process: Fermented in Saison Yeast 
Notes: Clementine, Thyme, Clover Honey 



Introducing Meddle

Introducing Meddle

Meddle Coffee Bar


DMC is proud to announce the opening of our new location, Meddle! We are super excited to have the world's first Psychedelegance coffee shop! The grand opening date will be Friday, October 21st at 6:00am! 

Below is a brief story of DMC, Meddle's hours and location. Thank you all so much for being a part of this magical Family, we couldn't have done it without the support!! 

Conceptually, Dark Matter resembles a rock 'n roll band, with each location representing "albums".Using this philosophy, Star Lounge Coffee Bar was our freshman album, a break through that continues to energize the Chicago coffee scene. We rapidly gained accolades for our community driven movement with quality as the core focus. Soon after came our roastery, "The Mothership - Intergalactic Headquarters" a hub for experimentation and continual education. An innovative and rule breaking sophomore record, structured around four different roasting machines to profile coffee in ways that had not been approached yet. The headquarters also added new staff in our cosmic army, increasing our fuel for the masses, energizing and creating a new portion of the material universe that is here to stay.

Having successfully conquered the "sophomore slump", we decided to take the time and create another experience outside of our Humboldt Park/Ukrainian Village comfort zone. We took our ideas to the long established neighborhood of Lakeview to open the infamous "Osmium Coffee Bar." (Video recap.) Osmium quickly grabbed the attention of the north side of the city with it's oozing chocolate walls, and thirdeyes watching over the chrome and blue soaked environment. This third location further identified each individual store with unique but extreme differences in design and neighborhood feel, avoiding any replication between locations.

Which brings us to Meddle Coffee Bar, our first downtown shop. After countless sessions with the beyond talented muralist, Jason Brammer, we coined our image for Meddle as "Psychedelegance". With purple swirling floors, white subway tile with black grout,datura trumpets ripping out of the bricks, a coffee jungle coming to life, and purple neon so alive it brings flashbacks to the forefront of your brain, Meddle brings our counter culture spirit to the West Loop neighborhood.

Meddle Coffee Bar
601 West Jackson Blvd
Chicago IL 60661
Hours of Operation
Mon - Fri 6:00am - 6:00pm 
Saturday & Sunday 8:00am - 3:00pm 



April 19, 2024 — Kyle Hodges
Hop Fermented Coffee

Hop Fermented Coffee

Several years ago amidst the ice coffee mania we saw our friends Oddly Correct Coffee doing a really cool variant using a cold coffee extraction with dry hops. We always thought that was so rad and asked ourselves how we could riff on that idea. So we played with some dry hopping in pour overs Half Acre Beer one year when we were brewing coffee for ‪#‎BIGHUGS‬.

Coffee fermentation is a major focus for DMC, it's one of the many areas that separates us from our peers. More specifically, we are trying to grasp a better understanding of fermentation's nebulous process and then modifying our approach to achieve a desirable result . In this experiment, we wanted to see how the acids in hops would affect the microbiology present in fermentation tanks and more importantly, how the hop character would impact flavor. So exactly how does this hop fermented coffee process work? 

Hop pellets are potent little capsules that contain gargantuan levels of acidity, spice, and fruit. Managing the exact hop dosage is very important to get the desired effect in the final product. Catuai was chosen for this experiment because of its stability and consistency, two characteristics that helped to gain more control when conducting experiments. To make a long story short, the end result was essentially dry hopping three different fermentation tanks holding the Catuai, each with a different hop. Citra, El Dorado, and Mosaic hops were chosen because of their differing characteristics with spice, fruit and herbal notes . This will be an ongoing project we will continue to hone in on. Its difficult to say where this experiment will lead but we are excited to sink our teeth into this one for years to come!

These three coffees were released in 2016, the first dry hopped coffees being sold in the world, all with roaring success. We even decided to dry hop our Chocolate City iced coffee for several events, CBC Boston & Copenhagen, Lollapalooza and special offerings at our retail locations. Expect to see more hopped coffee releases, both iced and whole bean in 2017! 

El Dorado Hops

Country: Guatemala
Farm: San Jeronimo Miramar
Cultivar: Catuai
Hop: Fermented with El Dorado Hops
Notes: Cantaloupe, Honey, Milk Chocolate


Citra Hops

Country: Guatemala
Farm: San Jeronimo Miramar
Culivar: Catuai
Hops: Fermented with Citra Hops
Notes: Cocoa, Orange, Pineapple

Mosiac Hops

Country: Gautemala
Farm: San Jeronimo Miramar
Cultivar: Catuai
Hops: Fermented with Mosiac Hops
Notes: Plum, Pear, Lemongrass 

Beer & Coffee Lovers Can Finally Have It All!

Beer & Coffee Lovers Can Finally Have It All!

DMC are crazy beer geeks just like you. From our collaborations, to our packaging, etc, it's a fact that we love beer. Now we have taken things a step further and incorporated different fermentation using ingredients that make beer possible. These experimental processes are new to both the DMC inventory and the coffee community as a whole. Our goal is using a culinary approach to coffee, combined with knowledge, and fun, we learned from our many beer collaborations over the years. Now combining all that together, we are ready to introduce a new series of coffees that will satisfy even the biggest beer geek/coffee fanatic out there. 

These releases will be a combination of single origin and blends, using hopped or yeast fermented coffee. (Just like the beer making process) The first two in the series, Citra hops and Saison yeast, were also released last year, with great success. This year's harvest is no different, yielding yet another round of delicious coffees. 

Future releases will involve the following yeast or hops. 
Crystal Hop Fermented Catuai
Beer Blend (Combining one yeast and one hop fermented coffee.)
Bohemian Weiss Yeast fermented Catuai
Hallertau Blanc Hop Fermented Catuai

Saison Fermented Catuai

Saccharomyces cerevisiae is a species of yeast primarily needed to produce beer, wine and bread. Because of the abilities of this microbe, Saccharomyces has become one of the most studied and cultivated organisms in the world.

Yeast, a type of fungi, is a single cell organism needed for coffee to be processed. To be clear, coffee fermentation doesn't need Saccharomyces, as there is a whole universe of other yeasts out there for fermentation. Fermentation tanks usually consist of a soup of microbes that also feed on coffee sugars and are almost always open air, and made of cement. Beer, wine and bread need the byproducts of yeast for them to be successful and gain complexity and flavor, while coffee does not. At the very least, coffee needs microbes to break down the sugary gelatinous layer of pectin surrounding a coffee bean to be dried properly. We've purposefully inoculated coffee fermentation tanks with Saccharomyces so we can layer the esters and acids it produces into the coffee.

When propagated, yeast will live the most amazingly simple life on the planet - it eats, it mates and sleeps in abundance, and if it's happy, that's all these critters will do their entire life. All yeast strains have slightly different preferences to be happy but overall they need:
-water with regulated temperature and pH
We've had great results from Saison yeast in the past. It's sturdy and not particularly fussy over its environment or *food*. Characteristics like this are ideal for us, due to the unruly and unpredictable nature of open-air fermentation tanks. Saison yeast produces esters and phenols that give saison beer their signature flavors - think bubblegum, banana or clove. As the coffee sits, it can absorb these flavors and take on a unique set of characteristics.

Once the saison yeast is active, we add it to the fermentation tank with freshly pulped coffee. This process fundamentally alters the ecosystem of the tank. The combined characteristics will stay present through the rest of processing, roasting and finally brewing.

Citra Hopped Catuai
We have played with hopping coffees using two processes. Currently, we send out iced coffee brewed with Citra hops, but this process is not related to this whole bean coffee. 

In this process we added dry hops to freshly pulped coffee in a fermentation tank at the farm. Hops flowers have resin glands that produce bittering compounds that inhibit microbial production. The dissolved hops make a "marinade" for the coffee to ferment. Similarly to the saison yeast, the roasted coffee has a subtle layer of hop character, which should add juicy fruity qualities to the bean.

April 19, 2024 — Kyle Hodges
Great Lakes Tattoo Collaboration Blend & Event

Great Lakes Tattoo Collaboration Blend & Event

Look for the Great Lakes Tattoo Blend to premiere at the Walk Up Classic on March 18th, available in Dark Matter retail stores and online thereafter
 “Once you've come to be part of this particular patch, you'll never love another. Like loving a woman with a broken nose, you may well find lovelier lovelies. But never a lovely so real.” - Nelson Algren, Chicago: City on the Make
Two prominent Chicago-based businesses, Great Lakes Tattoo and Dark Matter Coffee, have collaborated for the first time on a limited edition coffee: the Great Lakes Tattoo Blend.  To be released at Great Lakes Tattoo’s flagship event the Walk Up Classic (March 18th and 19th, 2017) and available in Dark Matter retail stores and online shortly thereafter, this blend comes from beans from El Salvador and covers a range of colorful characteristics; like our city, it’s loud, complex, and always genuine.  Something that everyone can enjoy.  Great Lakes Tattoo aims to capture all that Chicago offers: the grit, the beauty, the strife, and calm, and is dedicated to preserving the history of tattooing in Chicago and determined to make history of its own.
This partnership comes in conjunction with Great Lakes Tattoo’s second annual Walk Up Classic, which features 22 artists from all over North America who converge for a two-day convention-style tattooing event.  Last year, the artists were able to complete over 200 tattoos in two days and this year, they will undoubtedly surpass that.  GLT recently announced the full lineup of artists that will participate this year, which features some of the most vital and influential tattooers in North America:
Beau Brady (Captured Tattoo - Tustin, CA)
Steve Byrne (Rock Of Ages Tattoo - Austin, TX)
Greg Christian (Tattoo Faction - Cleveland, OH)
Nick Colella (Great Lakes Tattoo - Chicago, IL)
Mike Dalton (Great Lakes Tattoo - Chicago, IL)
Mario Desa (Great Lakes Tattoo - Chicago, IL)
Chip Douglas (Port City Tattoo - Long Beach, CA)
Brad Fink (Iron Age Tattoo - St. Louis, MO / Daredevil Tattoo - New York, NY)
Erik Gillespie (Great Lakes Tattoo - Chicago, IL)
Tony Hundahl (Rock Of Ages Tattoo - Austin, TX)
Marina Inoue (Traveling Tattooer)
Jen Lawes (Pearl Harbor Gift Shop - Toronto, ON) 
Kevin Leary (Great Lakes Tattoo - Chicago, IL)
Nikki Lugo (Tattoo Paradise - Washington, DC)
Miles Maniaci (Great Lakes Tattoo - Chicago, IL)
Angelo Miller (Inksmith & Rogers - Jacksonville, FL)
Mike Rubendall (Kings Ave. Tattoo - New York, NY)
Robert Ryan (Electric Tattoo - Asbury Park, CA)
Dan Smith (Captured Tattoo - Tustin, CA)
Scott Sylvia (Black Heart Tattoo - San Francisco, CA)
Glennie Whittall (Pearl Harbor Gift Shop - Toronto, ON) 
Matt “Beatdown” Ziolko (Great Lakes Tattoo - Chicago, IL)
Between the hours of 11am and 7pm on Saturday and Sunday March 18th and 19th, clients will be able to walk in and select designs to be tattooed the same day - no month-long waiting lists or multiple sittings, no attitudes or egos, just efficient and reliable tattooing in a relaxed and enjoyable atmosphere - by some of the greatest tattooers in the country.  Additionally, GLT will host an opening party and flash preview the evening of March 17th where clients can choose from designs prepared by all participating artists exclusively for the Walk Up Classic.
More news and information about Great Lakes Tattoo's Walk-Up Classic 2017 is below.  For now, keep up with the GLT crew on Instagram @greatlakestattoo and on Facebook.com/GreatLakesTatooCo and follow Dark Matter Coffee at Facebook.com/DarkMatterCoffee and on Instagram at https://www.instagram.com/darkmattercoffee.
When: March 17, 18 & 19
Opening reception: March 17th from 7pm-10pm
Walk Up Classic Tattooing Hours: March 18th & 19th from 11am-7pm
Where: Great Lakes Tattoo, 1148 W. Grand Ave.  Chicago, IL 60642
April 19, 2024 — Kyle Hodges
Maplewoodstock 2016, Our 9th ANNIVERSARY PARTY!!

Maplewoodstock 2016, Our 9th ANNIVERSARY PARTY!!

Maplewoodstock 2016

Come one, COME ALL to the 9th Anniversary party for Dark Matter Coffee!!

Maplewoodstock 2016 will happen on Saturday, July 9th from 12:00 - 8:00pm on Maplewood Street (between Iowa & Chicago Ave) 

We gathered a bunch of our music, beer and food friends to once again throw the best block party in Chicago, with ALL proceeds going to Hope For The Day!!! You read correctly, the food, music and beer are on DMC so that everyone's hard earned dollars can help make an impact through HFTD's amazing programs.

If you are unfamiliar with HFTD, they are a Chicago based non-profit that brings awareness to mental health and suicide prevention, both invaluable services that are greatly needed throughout the world. They provide resources, activities and help bring about legislative changes to not only people with mental illnesses but their friends and family who support them. DMC are proud partners with Hope For The Day and hope that you too will come and support their efforts. 

Speaking of party, have you looked at what is about to take place?? The music line-up, FOOD and THE DAMN BEER LIST?? It's all top notch and ready for you to come get down!! Now, there will be some rules put in place to make sure everyone is safe.


1.  If you plan to drink, you MUST HAVE A CURRENT ID stating that you are indeed 21+. No ID, no beer, NO EXCEPTIONS! 

2. This is a family friendly event, we encourage everyone to attend. There's even ice cream for the kids, thanks to Ruth & Phil's ice cream. (For BIG kids too!) 

3. Please bring extra water as the day will be hot. There will be some delicious water available, courtesy of our friends at Essentia Water but hey, more water won't hurt anyone! (Plus there are like plenty of places to deposit all that extra water, if you know what we mean ;) 

4. Food - We will have a large amount of FREE food from friends like Lockdown, Roots Pizza, Sauce & Bread Kitchen and Uncle Dougies. This food will be given out throughout the event, so please make sure to eat and also share with your fellow party people. 

5. No outside booze please! There will be plenty of beer for everyone so please, save the flasks and rare bombers of beer for after 8:00pm when our party ends. 

6. Finally, this is a block party celebrating our neighborhood. Which means the neighbors will be home. Don't worry, they are cool as sh*t and love having everyone over. That being said, please respect their space and stay within the parameters of the party. Only go in their lawn, patio, etc if you are invited. 



Band of Bohemia

Central State Brewing

Dark Horse Brewing

Devil's Trumpet

Forbidden Root Fine Botanic Beers

Goose Island

Half Acre Beer

Local Option Brier

Marz Brewing


Off Color Brewing

Penrose Brewing 

Perennial Artisan Ales 

Pipeworks Brewing 

Revolution Brewing   

Rockwell Brewing

Scratch Brewing

Virtue Cider

3 Floyd's 

18th Street Brewery



The Right Now - Black Bear Combo 

Wild Jesus & The Devil's Lettuce

J.A. Grimms & Blackknight - Ben Ezra

Buckingham Palace SVU - Malci & The Lobster Bisque  


Tim Zawada (Star Creature Universal Vibes) - Chuck Wren (Jump Up Records)

Sonorama DJs (Sonorama Records) Twinpeaks DJs (Press Pot Recordings)

NOT Beer

Essentia Water 



Roots Handmade Pizza

Phil & Ruth's Gourmet Ice Cream

Sauce & Bread Kitchen

Uncle Dougie's

April 19, 2024 — Kyle Hodges
Do Rite + Dark Matter Coffee = Vanilla Suburbs

Do Rite + Dark Matter Coffee = Vanilla Suburbs

Press Release from Do-Rite Donuts for the new DMC collaboration.

You could say simpatico. You could say synchronicity. You could also say Vulcan mind meld. This is how we feel about our partners at Dark Matter Coffee. Why do we love our friends at Dark Matter Coffee? They are innovative and ethical, interesting and tenacious, artistic and inspired. Their community stretches from the streets of Chicago to the coffee farms of El Salvador, Guatemala and Mexico. The
result of their efforts resides in every cup of coffee we serve at Do-Rite.

Our newest collaboration donut is the Vanilla Suburb. Inspired by George Clinton and the Parliament Funk lyrics, this embodies the complexity of the Dark Matter philosophy. It’s a raised donut with not one, but two fillings. The first is a Chocolate City coffee infused cream, the second is a chocolate ganache with a hint of cayenne. Finally, it’s dipped in a real vanilla bean glaze and finished with some
chocolate latte art (as coached by Dark Matter’s Jesse Diaz). These wonderful things will be at both Do-Rite shops and all 3 Dark Matter locations for the next 3 weeks. And we are pretty comfortable suggesting some coffee to go with that.

Coffee Processing And What It Means

Coffee Processing And What It Means

There are many avenues and ways to explore what goes into making a great cup of Dark Matter Coffee. With this post, we will help to explain all of those important parts by first starting with sourcing the coffee from the farm and how processing affects how coffee tastes. 

To begin, we  will look at the anatomy of a coffee cherry, then move to explain different ways coffee is processed. 

The Guts of a Coffee Cherry



Structure of coffee berry and beans: 1: outer skin/pulp 2:Mucilage/pectin layer 3: parchment 4: silver skin/chaff 5: bean/center cut

  1. Outer Skin / Pulp: The outer skin/pulp are covered by a skin, very similar to that of a cherry. This skin is usually removed from the fruit after the fruit is harvested. The exception is Natural Processed coffees, which leave the outer skin on during fermentation. The flesh, called cascara, is often recycled into compost at farms but has recently been used in making a drink that resembles a tea. 
  2. Mucilage: After the skin comes the mucilage. This layer surrounds the coffee seeds with a sticky, sugary substance and gives the Honey process its name. 
  3. Parchment: This is a cellulose layer that protects the coffee bean and resembles parchment paper when dried. 
  4. Silver skin / Chaff: The final layer covering the seed is called silver skin due to it's silver-like sheen. During the roasting process this skin drys and falls off becoming chaff. Chaff is normally discarded waste but can be used in gardening and sometimes can be found in bags of coffee if it doesn't separate from the bean during the roasting process.  
  5. Center Cut / Coffee Bean: The bean, THE GOOD STUFF, is what we are all searching for. Two seeds are found inside each coffee cherry, (Peaberries being an anomaly, with only one seed/bean inside. We will discuss this in a later post.) This is what we roast to DMC standards for the perfect coffee experience!

Main Processing Methods Used In Coffee

There are three main processing categories used in processing coffee. The difference between the three methods can be defined by the amount of layers of the layers listed above before being dried.

      1. Natural or Dried in the Fruit Process – All the layers remain intact. This is the oldest and most direct way to process coffee. Careful attention must be paid to how the coffee is being dried to prevent any moldy or weird flavors don't get into the beans during the process. Coffees that use this method generally have a brighter, more fruit forward flavor profile. 

      2. Honey Process – The skin and pulp layers are removed while keeping a portion of the mucilage layer. Remember, this sugary layer is what defines the Honey process. These coffees have significantly less acidity than Washed or Natural coffees due to the short amount of time it takes for the mucilage to dry, resulting in less fermentation. The length of drying time and exposure to the sunlight will determine what type of Honey process it is called. Yellow, Red, or Black are descriptions used to help describe the length of time and amount of light exposure that each coffee receives during the drying process. 

      3. Yellow Honey  Also known as semi-washed, this coffee is rinsed with minimal water to wash off excess mucilage. Later, it is exposed to direct sunlight to dry quickly and control fermentation, this style of processing is the least fermented of the "honey" processes and is effective for boosting body and sweetness in a cup.          Yellow Honey Process  (This is a machine washer for coffee turned up to its most powerful setting. It is used for the "yellow honey" or semi-washed process. Though Federico Pacas says, this style would be more like "white honey" when used to this extreme. The cherries are moved up while the mucilage is dripping down to leave just a touch of that magical Miel on, before the dry fermentation and then off the drying beds)          
      4. Red Honey This process does not necessitate water and instead is dry-pulped and exposed to direct sunlight up to a period of two to three weeks. Slightly more acidity is present in the cup but also maintains a great deal of sweetness.   
      5. Black Honey The most labor-intensive of the honey processed coffees due to the longest drying times and intentionally sheltered from the light to allow yeast and bacteria to thrive and produce higher amounts of acidity. Some of its characteristics in the cup can be similiar to that of a natural due to the extended fermentation process. 

        (Aaron Campos, Dir of Coffee for DMC, and Federico Pacas look over black honey processed bourbon cultivars from Finca San Jose in El Salvador!)

      6. Washed Process –This process is also called wet processed because the skin, pulp and mucilage are all removed using water and fermentation. In this method, a machine called a depulper removes the skin of the coffee cherry. Fermentation tanks are the next destination, with the coffee remaining in the water until the mucilage is broken down and the beans are no longer sticky. If the green coffee is left in the water too long, over-fermentation can happen, with the results being a sour tasting coffee. The washing process is a neutral expression of fermentation as it only yields characteristics natural to the cultivar - bacteria and yeast do not produce esters or acids to alter flavors in the cup.  





April 19, 2024 — Kyle Hodges
Blood Fight!!

Blood Fight!!

Calling Street Fighters out there, DMC will be fueling the fighters as they go toe-to-toe on Saturday, April 9th at Ignite Gaming Lounge. We are putting some skin into this tournament, with DMC's own Rick "White Lightening" Joyce, the meanest son-of-a-bitch to ever grip a gaming controller. If you think you handle this bizness, then sign up for the tournament, featuring some cool prizes from DMC and Steel Series


April 19, 2024 — Kyle Hodges
Finca San Jeronimo Miramar

Finca San Jeronimo Miramar

A large group of employees recently went to visit our farming partners in Guatemala at Finca San Jeronimo Miramar. The group consisted of baristas, managers, office and roasters, all enjoying the chance to see how the coffee is actually made. For several, this was their first experience on a coffee farm, while others, it was a chance to reconnect with the beautiful land and generous people! 

Enjoy some of the pictures that help explain some of the different areas of the farm and how they are involved in creating all of the delicious coffee exclusively for DMC. 

Finca San Jeronimo Miramar Nursery
1.) Hybrid Nursery - an area near the main house on the farm. This nursery helps bring the new plants up to standard so they can be planted later into the fields. 
Bourbon Faro
An heirloom bourbon from Finca El Faro
Grafted coffee seedling
2.) Grafting - This technique is used to create new hybrids of plants, helping the farm to avoid disease and create new cultivars of coffee. This one has a robusta (used for rootstock) on the right & a soldier Catuai on the left. The end result is a tree resistant to rust & bearing tastier fruit.
Copper tips

3.) Copper tips - The end result of the grafts. Copper tips denote the rust resistant trees like robusta, typica, liberica...

Cola de Goya
4.) Cola de Goya - These red, palm like trees are grown to become Amarkers for lots of different cultivars & to allocate space throughout the fields.


5.) Volcanic Fields - A field of mature trees higher up the side of the Atitlan Volcano.

Lake Atitlan
6.) Lake Attitlan Sunrise - The lake is drawn through the base of the volcano, purifying the water even further and utilized in most facets necessary on the farm.
Tony & Sunflower
7.) Sunflower & Tony - the AGM & GM of The Mothership at origin, in the volcanic fields.






April 19, 2024 — Kyle Hodges