Pro Tips: Recipe Notes

October 26, 2016

Since I’m leading another workshop tomorrow at Goucher College, I thought it would be good to post some updates on our previous recipes, now that I’ve been making them for several more months.

Wild soda ginger bug

At some of our past workshops, the ginger bug sodas we brought along were super sweet and practically volcanic in their carbination. For my recent sodas, I’ve lowered the amount of sugar a little bit, but most importantly, you should be sure to wait an entire week after you bottle the finished soda. If you’re hasty and open it up before the yeast has finished processing the sugar, it will still be suepr sweet, and the active yeast will be pumping out loads of CO2. Wait for them to finish their magic, and settle down to the bottom of the bottle. Especially if you put it in the fridge for a day or two at the end, your soda should be crystal clear, with all the sediemnt at the bottom.

Ginger Bug Updates: 

  • For the soda: Use 1/3 cup sugar per 3 cup water
  • Ferment at least one week, and chill in fridge for a day before opening.


Sourdough bread

Sourdough Bread 

I’ve settled into using the Tartine Country Bread recipe for regular use. It produces a fantastic bread that is totally worth the effort. You can sub in other flowers like rye or buckwheat for part of the flour bill. Here’s a nice video that shows the folding process. Check out 11:40 for a great technique for wrangling that high-hydration dough.

As for maintaining your starter… Always keep the volume of starter at less than half the volume of your container; it needs space to rise after each feeding, and you don’t want to make a mess. For maximum sour flavor, feed for several days beforehand, and smell it until the starter is really sharp and sour. The sourness peaks after the starter has risen and then fallen; when you first feed the starter, it will be largely unfermented dough, and thus not very sour-tasting. Results will vary, but the starter usually rises over the course of 8 hours and then falls. So if you want to begin your leaven in the evening, I would feed your starter in the evening too.

Beer Tasting (6 months)

The wild beers produced during this project ought to age about a year before the fermentation is truly finished, but as the Turf and Terrain exhibition comes to a close, we wanted to drink some beer and close out the project properly. So after bottling the beer (see Broadcasts from a couple weeks ago), we’re tasting it at 6 months. Some of the flavors are less than desirable, and hopefully they’ll taste better in another six months.

Bad news: this is the last week of broadcasts! Good news: it's time to drink some 🍺! This traditional lambic was made with a lively mix of wild yeast and bacteria from Foggy Bottom. Moderately tart, lemony and apple flavors

Wild Lambic #1: The full boar batch made with two different starters, each batched up from the original samples collected in Foggy Bottom. More tart than fully sour, this beer has a deep flavor profile that includes lemon and apple aromoas (from malic fermentation?) and a funky base note. It’s super flavorful and pretty strong, so more of a celebration ale than an easy-drinking beer, but hey, that’s what we’re here for.


Our second wild beer was made with a single strain of yeast isolated under a microscope. Probably brettanomyces because it tastes super farmy with deep bitter notes. It's still aging, so may improve with time

Wild Lambic #2: Full Brett – after isolating yeast through agar plating, it seems that the yeast cells we identified were the wild and unpredictable Brettanomyces rather than the tradional Saccharomyces. This makes sense, since there’s more of that floating around in Washington D.C. than brewer’s yeast.  The flavor has evolved somewhat from a serious horse blanket flavor just after fermentation began, to more of a bitter farmy flavor. Not reccommended. Pictured above: the offending yeast.


The third batch of wild-fermented beer was a blend of isolated brettanomyces and commercial kolsch yeast. It tastes pretty funky with a sharp band-aid smell. Hopefully it will also mellow out with time

Wild Cream Ale: Brewed as a tribute to the German historical brewers of Foggy Bottom, this hybrid of a Cream Ale (an ale trying to be a lager) and a wild lambic was brewed with a mix of Kolsch and wild yeast. Unfortunately the wild yeast we used was the horsey Brett from Lambic #2, so the overall flavor is still super funky. Combined with the commercial Kolsch yeast, the flavor comes off as band-aid with a sharp tang.

Brined Beets

September 15, 2016

pickled beets

This recipe is a great place to start with fermenting vegetables (along with sauerkraut), and one that I’ve had in the back of my fridge pretty much constantly for the last year or so. It come from the Bar Tartine cookbook, which is terrific resource for pickling, fermenting, and making radical pantry items like homemade vinegar or smoked onion powder.

Pickled beets taste complex and fantastic. To make them even more flavorful, this recipe has you blend some aromatics into the brine to make a super flavorful liquid (once it’s full of live cultures, it’s like a shot of magic elixir). I’ve found that depending on the size of your beets, they can still be quite crunchy after 1 month of fermentation, so I like to cut them up into sections as seen in the photos. These are awesome in salads or as a snack, or anywhere you might use regular beets.

Ingredients (makes 2 qt)

  • 1 tsp black peppercorns, toasted and ground
  • 1 tsp coriander sees, toasted and ground
  • 1 star anise pod, toasted and ground
  • 1 tsp mustard seed, toasted and ground
  • 1 tsp fennel seeds, toasted and ground
  • 1 bay leaf
  • 3 lbs red beets, peeled
  • 1 bunch fresh dill
  • 1 cup / 140g kosher salt (sea salt weighs differently!)
  • 4 qts water
  • 6 garlic cloves
  • 1 shallot
  • 1 Serrano chile, stemmed


  1. Toast seeds and put in a sack of cheesecloth or reusable pouch.
  2. Chop beets to desired size.
  3. Add beets, dill, and spices to a large non-reactive container.
  4. In a separate container, dissolve salt in the water to make the brine.
  5. Transfer about a cup of the brine to blender, and add the garlic, shallot, and chile; process until smooth.
  6. Mix the puree back into the brine and pour over the beets.
  7. Place a weight on top of the beets to keep them submerged. If you need more liquid, mix additional brine by combining 1 cup water with 1 Tbsp kosher salt.
  8. Seal the container with an airlock if you have one, or else seal with a lid and open every few days to release carbon dioxide build-up. Alternatively, cover container with a loose towel or plastic bag and scoop off any mold that develops (white mold is fine, just check on your beets every few days and be vigilant).
  9. Store in a low-light environment between 60-70°F until beets taste sour, about 1 month.
  10. Transfer to an airtight container and refrigerate for up to a year.

Lambic Update

August 16, 2016

wild lambics in carboys


I currently have three 2.5 gallon batches of wild fermented beer aging in the cellar, I just sampled all three to see how they’re coming along.

Lambic #1

This was a traditional grain bill of pilsner malt and wheat, lightly hopped with Czech Saaz, and pitched with two different yeast starters. This was soon after the Microobservatory opened, so I didn’t isolate the yeast, but batched up several starters, until they had gone through several rounds of fermentation. I chose the two the smelled the best, and let them get to work; meaning that this lambic is a truly wild blend of microbes. I also threw in a small oak spiral to simulate the traditional lambic technique of aging on oak.

Four Month Update: Tastes moderately tart (4.0 pH), and reminiscent of cider with strong lemon and apple notes, and a bassy funk flavor coming in the background. Gravity is practically at 1.00 at this point, estimating 6.5% ABV which is pretty strong for a lambic.

Lambic #2

For this batch, I plated a promising-smelling starter to an agar plate, and isolated a yeast colony from that, batching it up and examining it under a microscope to confirm a mostly uniform population of yeast.

Two month update: Tasting this provides a seemingly note-perfect example of the “horse blanket” flavor often mentioned in discussion of beers made with Brettanomyces strains, suggesting that the yeast I carefully isolated was a larger Brett cell instead of the more traditional Saccharomyces cerevisiae. Flavors of wild beers can change substantially over time, and this beer is still relatively young, so hopefully it will evolve into something more drinkable. The sample had some small yeast flakes in it, suggesting that there’s still some sort of fermentation going on in there.

Agar plate

Pretty sure this was the yeast isolated for Lambic #2

Wild Cream Ale

I previously wrote about the story behind this recipe, a hybrid between experimental wild ales and the traditional lagers of Foggy Bottom’s German breweries. Most importantly, this was fermented with a blend of commercial Kolsch yeast and the wild yeast isolated for Lambic #2.

Two Month Update: Tastes as expected… a kolsch blended with some wild Brett flavor. The horse blanket is more subdued here as it’s somewhat masked by the flavor of the commercial yeast. Also hoping this one will clear up and taste more like a lager over time.



Isolating Yeast

July 2, 2016

agar plate yeast

This post continues from the previous instructions for making agar plates, so be sure to read that first, you’ll need the plates for what comes next.

The finished agar plates should be a sterile way to observe the development of yeast colonies. The gelatinized wort forces yeast to sit on the surface of the “liquid” rather than floating freely throughout the wort. As the yeast consume sugars present in the wort, they will multiply, and visible blob-like colonies will appear along the areas of the wort that were exposed to the yeast. Becasue yeast multiply like crazy, we only want to add the tiniest amount of yeast to the plates—through a process called streaking. As before, visit Bootleg Biology for more information and to order supplies.


  • Paper clips
  • Lighter or butane flame
  • Agar plates
  • Saran Wrap or medical tape



  1. Unbend a paper clip and sterilize one end of it until glowing red.
  2. Let cool 30-60 seconds (to avoid killing the yeast on contact).
  3. Dip the end of your paper clip into a sample of yeast or beer sediment.
  4. Streak the sample across one side of the agar plate in a series of quick parallel lines.
  5. Sterilize the paper clip again and let cool.
  6. Streak the plate perpendicular to your first lines, dragging through the original streaks.
  7. Repeat two more times forming a diamond, with each round dragging out a bit of yeast form the previous streaks, essentially thinning out the already minuscule amount of material (see diagram below for a visual guide).
  8. Cover the plate and wrap it in plastic wrap or medical tape to create a good seal.
  9. Store in a room temperature dark environment for several days until you see yeast colonies start to develop.
Agar plate streaking instructions

Sterilize clip between each round of streaking and drag through the previous marks to gradually thin out sample.

Agar Plates

June 29, 2016

agar plates

The following Agar Plate technique is based on the instructions and equipment available at Bootleg Biology. I recommend reading through their notes as well, but for the sake of chronicling the experiments at the Microobservatory, I’ll provide my own recipes and tips here.

If you’ve followed one of the techniques for collecting wild yeast, you will end up with a small jar or vial of bubbling starter wort. After a few days you should see some bubbling and hopefully a thick krausen. In 1-2 weeks you should see the krausen subside, indicating that the fermentation has run it’s course and the yeast have settled out at the bottom of the fermentation vessel. At this point you should smell the liquid—it smells good, great! If it smells bad, throw it out and start over! Most of the wild yeast I’ve collected ends up smelling lemony and tart, usually funky to one degree or another.

A note on safety: At this point, the fermentation will have made the wort more acidic and produced a tiny bit of alcohol. If any unwanted microbes made their way into the wort, they will probably have been killed or rendered inactive by the harmful conditions. We can increase the odds of eliminating unwanted microbes by batching up the wort into a larger volume of beer (essentially a second fermentation that adds more alcohol and further lowers the pH), or desired microbes can be isolated from the teeming ecosystem of your starter wort by using agar plates.

Create Agar Plate

Additional instructions at Bootleg Biology


  • Sanitized petri dishes
  • Saran wrap
  • Paper clips
  • Lighter or butane torch (or sanitizer)


  • 300 mL (10oz.) filtered water
  • 35g dried malt extract (DME)
  • 5g agar powder (sometimes listed as “Agar Agar Powder”)
  • Pinch of yeast extract (optional)


  1. Bring water to boil in a small saucepan and add DME, stirring to be sure that it doesn’t boil over.
  2. Boil for 15 minutes
  3. Remove from heat and stir in agar powder.
  4. Let mixture cool to below 100°F (about 15 minutes), keeping an eye on it to make sure it doesn’t set completely. The mixture should be thick but still pourable.
  5. Carefully pour mixture into petri dishes (I usually lay out a bunch of them on a baking sheet).
  6. Let the mixture cool until completely set, storing in a draft-free environment. You can cover them to avoid contamination as long as you make sure the cover itself is clean.
  7. Once set, put the lids onto each petri dish and tightly seal them with saran wrap.
  8. Store the dishes upside-down so that condensation will collect on the lid.
  9. Store prepared dishes in a dark draft-free location for one day. If mold appears in any of the dishes, you should throw out the contents.

Up Next: Streaking Plates!

Sourdough Bread

June 17, 2016


Sourdough bread loaf

It’s been a week, and you’ve got a sour-smelling starter bubbling away in your kitchen—time to make some bread.

For more authoritative recipes, take a look at Tartine’s Country Bread or the recipe at the Kitchn. Tartine Bakery in San Francisco is a renowned leader in breads and fermented goods. Their general cookbook, Bar Tartine: Techniques & Recipes is an invaluable source of information of fermentation, drying, and maintaining a living kitchen. So I’ve followed their recipe (giving some notes of my own), but it’s similar to many high-quality bread recipes.

This is a high-hydration bread, which means the ratio of water to flour is rathe high, or in other words, the dough is quite wet. This is necessary to achive that beautiful open-crumb structure that you see in artesional bread. The finished bread is nice and moist at first, and tastes quite sour.

Makes: Two loaves

Time: About 24 hours


  • Dutch oven, stainless steel, or ceramic pot with lid.
  • Proofing baskets or medium-sized bowls
  • Dish towels
  • Scale


  • Active sourdough starter
  • 200g whole-wheat flour
  • 1000g white bread flour
  • Additional flour for dusting
  • 20g sea salt




  1. Make the leaven* the night before. Combine 1 Tbsp. sourdough starter with 200g warm water, 100g whole-wheat flour and 100g white bread flour. Stir together and cover with a towel for 12 hours until the leaven has expanded and looks bubbly. Test the leaven by dropping a spoonful into some water; it should float (if it doesn’t, let rest a couple more hours).
  2. Make the dough: Combine 200g of leaven with 700g warm water and stir to incorporate (the remaining leaven can be kept as a new starter or mixed into an existing starter).
  3. Add 900g white bread flour and 100g whole-wheat flour and mix with your hands or a butter knife. The dough will be very sticky and ragged. Cover with a towel and let rest 25-40 minutes.
  4. Add 20g fine sea salt (seems like a lot, but remember it’s for two loaves; kosher works too) and 50g water. Stir again until dough comes together, it will look very wet, but keep stirring until you succeed.
  5. Cover the bowl with a towel and let rest for 30 minutes. Keep the dough in a warm place (yeast like to be comfortable!).
  6. Fold the dough by coating your hands in flour and reaching below the ball of dough. Imagine the dough has four sides, and pull each side (one at a time) up over the top of the center. Imagine folding a piece of paper in on itself from all four sides. Do this every 30 minutes for 2.5 hours. This is a very wet dough, but I found it necessary to add a sprinkle of flour each time I folded the dough to make it a little more manageable.
  7. Transfer dough to a work surface and dust with flour. Cut into two equal pieces and flip them over (flour-side down). Fold the cut edge of the dough in on itself so only the floured surface is exposed, work the dough into a loose round and cover with a towel for 30 minutes.
  8. Line two proofing baskets or bowels with towels and dust the towels with flour (Tartine uses rice flour, but it’s fine to use whatever is on hand).
  9. Flip your dough rounds over and fold all four sides in towards the center in a similar fashion to your earlier folding. Transfer dough to proofing containers, seam-side up. Cover with a towel for 3-4 hours.
  10. About 30-45 minutes before baking place a dutch oven or other oven-proof pot in the oven and heat it to 500 degrees F. If you have a pizza stone or baking steel, put that on the bottom rack to help regulate temperature and get the oven nice and hot.
  11. When ready, carefully remove your pot form the oven and prepare to transfer the dough into the baking dish. Dust dough (seam-side up) with a little more flour and flip it into the baking dish so the seam is facing down. Depending on how wet your dough is, this may be more of a pouring motion than a flip, but it will still turn out great. I assume with practice one gets a feel for it. Use a very sharp knife to quickly score the top of the dough a couple times to allow the dough to expand more easily. Carefully cover the dish with its lid and put the baking dish back in the oven. Reduce oven temperature to 450 and bake 20 minutes.
  12. Next, remove the lid and bake 20 more minutes until the crust is a rich golden brown.
  13. Remove the pot and transfer the bread to a wire rack (or similar surface) to let cool at least 15 minutes (though I’ve heard up to an hour to let the interior of the bread finish baking). The bottom of the loaf should sound hollow when you tap it.
  14. Clean out the pot and bake the second loaf.

Sourdough Starter

Sourdough starters are one of the more common household uses of wild yeast. You can buy sourdough starter, but where’s the fun in that? We’ll go over how to create a starter that reflects your kitchen’s unique micro-ecosystem. Like all yeast starters, you can use a small sample to build up a second batch, so if you know someone who keeps a starter, you can ask nicely for a sample.

This recipe is modeled after those found at Tartine Bakery and the Kitchn. You can use all-purpose flour or a mixture of half whole wheat half all-purpose.

Sourdough starter


  • 100g flour
  • 100g  filtered water
  • (If you prefer ounces, use 4 oz. each)


  1. Mix flour and water in a glass container, cover with cheesecloth and let ferment 2-3 days until bubbly (aim for low light and room temperature).
  2. After 1-2 days, once bubbles are appearing, discard half the starter and mix in 50g (~2 oz) each flour and water.
  3. Continue “feeding” the started daily until it is very bubbly, full of wispy air pockets, and smells quite sour—about 5-7 days.


No bubbles? Be patient, some yeast populations may be slower than others.

Layer of water on top of the mixture? This indicates that there is too much water in your mixture. Scoop of the water and carefully weigh the flour and water for your next feeding. Try adding a full 100g (4oz) of each just to bulk up the mix with the correct ratio of ingredients.

Forgot to feed the starter? It’s probably fine, just resume feeding as instructed.

Ginger Bug

June 14, 2016

Homemade sodas are a relatively fast way to capture some wild yeast and see them in action. I recommend it as an easy entry point into natural fermentation. Fermented foods like sauerkraut or brined pickles are also easy, but take longer to reach completion.


  • 6 oz. Organic Ginger
  • 3/4 cup Sugar 


  1. Grate 2 Tbsp. ginger. Leave the skin on it’s crawling with wild yeast!
  2. Measure 1 quart of filtered water into a glass container and stir in ginger and 2 Tbsp. Sugar.
  3. Cover with cheesecloth or nylon mesh and store at room temperature location, out of direct sunlight.
  4. Each day stir in an additional 2 Tbsp. each grated ginger and sugar.
  5. After 3-5 days you should see bubbles in the liquid and yeast sediment forming at the bottom of your container. When the “bug” is very bubbly, use some of the liquid to make a soda and store the rest in the fridge to slow fermentation.


Citrus-Ginger Soda Base

Use this recipe as a guide, and experiment with other flavorings like: grapefruit, berries, fresh turmeric, beets, spices, or even roots and bark (root beer!).  


  • 2 cups filtered water
  • 3/4 cup sugar
  • 2 lemons or limes (thinly sliced across)
  • 2” Ginger (thinly sliced)


  1. Mix all ingredients in a saucepan and bring to a boil.
  2. Reduce heat to medium and simmer for 15 minutes.
  3. Cool to room temperature, and strain into a resealable bottle*
  4. Add ¼ cup strained Ginger Bug to the bottle and top off with more filtered water, leaving about 1 ½” headspace between the liquid and the top of the bottle.
  5. Seal the bottle and let ferment 5-7 days. Chill before serving.


*Glass flip-top bottles work great, but if you use too much sugar or leave too much air (headspace) in your bottle, the yeast could produce too much CO2 and the bottle would break apart from the pressure. I have never seen this actually happen. Plastic bottles are also nice because you can check the carbonation by how firm the bottle feels when you squeeze it.


Historical Brews

June 10, 2016

I’ll be posting some recipes and tutorials here I go over some of the processes involved in natural fermentation in the Broadcasts, but I wanted to share a bit of the research that’s gone in to the wild fermented beers being made as part of our exploration of the Foggy Bottom neighborhood in Washington D.C.

One of the Microobservatory’s primary missions is to harness the wild yeasts and bacteria from the local environment and use them to brew site-specific beer. I’ll be going over sodas and fermented vegetables too, but beer holds special significance to the neighborhood as it was the home to several major breweries started by German immigrants in the 19th century.  Both the Heurich and Abner Drury breweries brought German styles of brewing to Washington, including lagers, marzens, and altbiers. Hailing directly from Germany, brewmasters Christian Heurich and Edward Abner probably used German lager yeast, perhaps mixed with American yeast collected stateside.

The Heurich brewery established in 1873 brought German brewing to Foggy Bottom - along with German yeast populations. #artsinfoggybottom #dcbrews #heurichhouse

Heurich Brewery

The Microobservatory imagines that those yeast are still out there, floating through Foggy Bottom, their charateristics decendant or even identical to the yeast used in the 18th Century. Unfortunately it’s very difficult to isolate specific strains of microscopic yeast, and any beers made through wild fermentation will probably include some microorganisms that the historic German brewers would have deemed undesirable. Besides the traditional brewer’s yeast, Saccharomyces Cerevisiae, our wild beer might also include Brettanomyces or bacteria like Lactobacillus or Pediococcus. The later three microbes, are typically found in traditional Belgian lambics, the one traditional style of beer to be fermented with naturally occurring yeast.

Lambics range from tart to very sour and include a large percentage of wheat in the mash bill (grains steeped in water to produce sugary wort). As our efforts continue to isolate a pure Saccharomyces strain, it seems likely that attempts at a wild Foggy Bottom beer will trend toward to sour lambic style —very different from the traditional German lagers of Heurich and Drury.

Heurich Lager can by DC Brau

Mike Stein and Pete Jones recently developed a recreation of the Heurich lager with DC Brau, and their recipe notes were helpful in developing some of the wild brews concocted at the Microobservatory. Their “lost lager” emphasized German traditions and used a Bavarian yeast strain, our wild Foggy Bottom brew will never be as predictable and clean as a traditional lager — so the question remained: what style to use as a template?

While researching the beers produced in historical Foggy Bottom, other styles came up such as a marzen and bock from Heurich and a cream ale from Abner Drury. The later of which exemplified the clash of German and American brewing that centered around breweries like the ones in Foggy Bottom. And what is a cream ale anyway?

At around the beginning of this century, the adjunct lagers being sold by the area’s new German brewers began to make inroads into ale sales. The public was beginning to prefer American lager’s light, clear, and effervescent appearance. Ale brewers responded to this demand by creating a top-fermented product similar to an American lager. Using ale yeast (or possibly even a combination of lager and ale yeasts, though no concrete evidence exists for the use of lager yeast in the early cream ales), they could produce beer more quickly than the lager brewers could, thereby potentially increasing sales and market share[…] These new beers were termed “brilliant,” “sparkling,” or “present use” ales, with the nickname “cream ale” sticking as the common name.


friarThese hybrid ales, in the style of German lagers (but fermented with ale yeast) seemed like a good way to pay tribute to the German legacy of Foggy Bottom while allowing a more flexible fermentation to cater to the wild microbes harnessed from the neighborhood.

I had already pitched a batch of lambic style beer with a lively mixture of local microbes, and wanted to try a beer fermented with a mix of wild and commercial yeast. White Labs makes a Cream Ale yeast but I ended up using their Kölsch strain (which is another light-bodied ale yeast that seems to mimic the results of lagering) to emphasize traditonal German flavors, along with a fairly isolated starter of Saccharomyces collected from the wild. These yeasts were pitched into a wort modeled after early Cream Ales — containing a fair amount of wheat and corn, adjuncts used to lighten the body.






Wild Cream Ale (2.5 gal. batch)

Mash Bill:

  • 3 lbs Pilsner malt
  • 1 lb Malted German wheat
  • 1 lb Flaked Maize

60 minute mash at 155°F

60 minute boil with 0.5 oz Czech Saaz hops added at start of boil

Whirlfloc tablet and pinch of yeast nutrient added at last five minutes.

Pitched White Labs Kölsch and 1 quart of wild yeast starter

Fermented in basement around 68°F. Good airlock activity the next day.