Cider Keeve: Day 123

This last weekend was the 4 month mark of the Cider Keeve.  I have checked in on this experiment at the 1 month and 2 month mark.  Here is a re-cap what is going on and what has happened, but you can go back and read those previous posts.

Keeving is an old world cider practice that removes nutrients from the cider.  During fermentation, the yeast runs out of nutrients and dies before it can eat all the sugar, resulting in a sweet cider.  The experiment I am doing is seeing what happens when you use a lambic blend of yeast to ferment the keeved cider and if this nutrient poor environment would allow me to mimic the typical lambic fermentation process in cider.  At month 1, I took a gravity reading and saw the fermentation tracking a slow fermentation characteristic of keeved cider.  This indicated that the yeast was fermenting in a nutrient poor environment, but still left the question open as to what would happen when the nutrients ran out.  Would the Brett continue to ferment or would it die along with the Saccharo?  At month 2, I took another gravity reading and the fermentation was still on track.  There seemed to be some Brett character when smelling the cider, but not much when tasting it.  This indicated that there was at least some Brett activity in tandem with the Saccharo fermentation, but I still didn't know if it would continue fermenting and reach 1.000 or if the Brett would die out.

On Friday evening I had some friends over and decided to check in on it with them.  Upon tasting, it was very clear that the Brett had continued on because there was an big earthy, barnyard flavor and aroma.  The gravity reading was 1.000.  Normally this would mean a thin body, which I feared, but to my surprise there was still plenty of body.  I am going to give this some more time to see how it continues to develop.  It seems like the Brett Brux dominated the other strains, so I'd like to see if any of the other strains will do anything in the next couple months.  I'll likely bottle this around the 6-9 month mark.

I'm very excited about this brew.  Its a whole new style of cider, and I really like the results.  I'm hoping we will do a larger batch this coming fall and ferment it in oak barrels (possibly ones previously used for lambic?).  I'll definitely be using East Coast Yeast next time instead of the Wyeast lambic blend smack pack. The Wyeast lambic blend is fine and served its purpose for this experiment, but I much prefer the flavor profile that results from ECY yeast blend.  It would also be fun to tweak the apple variety blend that goes into the press.

Cider Fermentation Panel: Yeast Pitched

Over the weekend I met with the guys at Leidel's Orchard to do our brett cider experiment.  The yeast arrived safely, the juice was ready, and they had purchased all the carboys/bungs/airlocks needed.

Wild yeast strains from East Coast Yeast

After we sanitized everything, we filled each carboy with 3 gallons of juice.  To ensure that our pitched yeast would be the source of 100% of the fermentation, the juice had been pasteurized at the pack house and then shipped to us frozen.  While we were waiting for the juice to warm up to room temperature, I dissolved 5 ounces of maltodextrin into some juice, and then added it to the juice already in carboy #11. (batch list here)

11 wild cider batches

Later that evening the yeast was added.  The only yeast strain that didn't come from East Coast Yeast was the B. Brux, which came from Wyeast.  24 hours after pitching every carboy except #5 (Brux) was in active fermentation.  #3 (Nanus), #7 (Fantome), and the brett blend batches were the most active.  Giving them a slight shake would almost blow out all the star-san solution in the airlock!

They will be left in that room, which is a steady 60 degrees, for the next month or two.  Unfortunately, the orchard is 2.5 hours from where I live, so I won't be able to check on it regularly, or take weekly gravity readings.  The goal of this experiment is primarily to see the flavor/aroma contribution of each of these strains and to find which ones we like in cider.

Cider Fermentation Panel

As I've mentioned in previous posts, I've been working with Leidel's Apple Orchard on a few hard cider pilot batches.  The past experiments have been more complicated, expensive, time consuming fermentation styles.  We now want to see if we could come up with a "table cider"; something that doesn't require oak barrels nor take 9+ months to ferment and age.

After giving some thought to the different kinds of ciders out there and how we could make something new and interesting, I got the idea of doing a 100% brett fermented cider.  Surprisingly, there is very little information out there on how brett (in general and individual strains) performs in cider.  Even in the homebrew world there are only a few people who have tried 100% brett fermentation for cider.  Most commercial cider operations (and a lot of home brewers) come at cider from the wine world, which hates brett, and so they refuse to even consider it.  So, coming from the beer world, specifically the "wild" beer world, it seems I have a fresh look at the possibilities.

First, we need to get an understanding of how each individual strain of brett performs and the flavors/aromas it creates in cider.  I would also like to get an idea of how brett performs when paired with a malolactic fermentation.  Apple juice has malic acid, which is a harsher acid.  Oenococcus can be used to convert the malic acid to the softer lactic acid.  In addition, I would like to see the impact of adding maltodextrines to a 100% brett cider fermentation.  Maltodextrins are complex sugars that normal brewing yeast is not able to break down and consume, leaving the beer with a fuller body and mouthfeel.  Theoretically brett has the ability to break these complex sugars down, but some home brewers have reported a difference in using maltodextrin with brett fermentation.

We decided to do test batch for all of the individual brett strains possible.  Once again I reached out to Al Buck at East Coast Yeast, who has been so helpful in the past, to supply the yeast.  In addition to providing the brett strains, he recommended a "wild" saccharomyces strain call S. Paradoxus.  I am particularly excited about this as it has the ability to do a partial malolactic fermentation on its own.

So here is the list of the 3 gallon batches we will be starting this weekend:

1. Brett drie (BSI)
2. Brett custersianus
3. Brett nanus
4. Brett lambicus (wyeast)
5. Brett bruxellensis (wyeast)
6. Brett claussenii (WL)
7. Brett fantome (ECY)
8. Saccharomyces paradoxus
9. Brett blend (drie, claussenii, fantome, ECY05)
10. Brett blend and oenococcus
11. Brett blend with maltodextrin addition

I'm really looking forward to this experiment.  I expect it to take a month or two to finish fermentation, but I will make sure to report the results here as soon as I have them.

Cider Keeve: Day 62

This weekend is the 2 month mark for the Cider Keeve so I wanted to check in on it, get a gravity reading, and see how it tastes/smells.  As I mentioned last time, I was anticipating a gravity of ~1.010, and at 1.008 it is going right as I hoped.

Keeved Cider at 2 months.

Now for the big question; how does it smell and taste?  To be honest, it was very hard to judge and the smell/flavor was not like any cider I've had.  The smell had this earthy, floral, and licorice combination with a hint of honey and apple skin.  It reminded me of a mead.  When I drank it, the flavor and body made me think I was drinking a mead or a wine.  My wife said it reminded her a lot of Chardonnay.  There was also a strawberry flavor and a slight tannin note.  It had a very nice tartness; not too sharp, but still pronounced.  At it's current gravity, I find it slightly thick, although if it were carbonated, it might be nice.

My biggest hope in checking in on the cider at this point was to see if the Brett was working in tandem to the Saccharo.  Based on the aroma, I would say yes.  However, it didn't translate much into the flavor...at least not at this point.  So I can't really say definitely if the Brett has been playing an active role or not.  I think it is on track for a keeve fermentation, and will just require some more time to see how flavors develop.

Since we were down checking on this, I decided to check on the Minimalist Lambic, which has been fermenting for over 7 months.  Gravity, as expected, is 1.000.  It smells pungent of typical lambic aroma.  Mostly grassy and barnyard funk.  Some hops and a slight phenol.  The taste was very interesting.  It has a very big funky/earthy/grassy flavor, but then has this lingering void, and then a hop bitterness.  The sourness is there, but not that high.  What is interesting is that its hard to call it "watery" or "one-noted", but it is definitely lacking complexity.  This isn't much of a surprise considering it is fermented with a single Brett strain where lambic traditionally has many many strains.

O'so Brewday & 1 year mark.

Two major events occurred this weekend.  On Friday, we brewed the second batch of lambic up at O'so Brewing, and today marks 1 year from the day I filled that first pilot barrel.  Its crazy how much a year can make a difference.  I went from being thrilled to get a single barrel filled to frustrated we didn't fill 15 barrels on Friday.

I'm not going to outline the process or talk too much on the brewing itself as I would just be repeating the previous brewday.  Instead, I'll mention a few of the changes between the batches.  The last batch hit 1.040 gravity, which is fine, but its on the lower end of the spectrum.  This time we upped the grain bill and hit 1.054.  In doing this we also got a darker wort, and I really like the color that resulted.

Another factor that helped us hit a higher gravity was the evaporation rate during the 4 hour boil, which is higher in the winter than the summer.  While I am happy to have the higher gravity, we only filled 13 barrels.  A 14th barrel was filled half way, and we will use that to top off the other 13 barrels after the active fermentation stage finishes.  In comparison, last year we easily filled 14 barrels and had probably 1.5 barrels worth of wort that had no barrel to go into and therefore went down the drain.

Filling the inoculated barrels

We also changed the hopping.  Last year we used 38 pounds of 5 year old Liberty hops.  In sampling the lambic at 6 months old, it has a fairly pronounced hop character.  I know this will fade, and have seen that happen to my pilot barrel, but we wanted to dial that down a notch and used 30 pounds of 5 year old Willamette hops.  The hop variety was not an intentional change, but rather simply what was available.

Measuring out 30# and breaking up the whole hops.

The most significant change we made this batch was to not pitch yeast.  Instead, we took the lambic barrels from batch 1 and transferred the contents over to new barrels.  Then we filled the inoculated barrels with fresh wort and will let it ferment with resident yeast in the barrel.  The "new" barrels were used wine barrels, and we soaked them for a month in water to further extract any tannin and wine flavor, then steam cleaned them.  I realize this lambic is going into new barrels twice and so wanted to make sure to increase my effort to strip flavor from the new barrels.  To rack the lambic from one barrel to another, we used a Bulldog barrel transfer set up.  First we pre-charged the empty barrels with CO2, then used CO2 to pressurize the filled barrel and gently push the lambic over to its new home.

Transferring aged lambic into "new" barrels.

All in all, it was another successful brew day.  Although I was especially disappointed in not being able to fill that 14th and 15th barrel, it is good to reflect on the year and realize how far this project has come.  I am thankful to O'so for brewing this beer with me, and I look forward to our annual brew day.

A sea of barrels.  All but the 6 stacked are for lambic.

Update:
It took 4 days to kick in, but fermentation is foaming over.

It started with these two on Tuesday night, and by Wednesday morning all of the barrels were foaming.  While I like that there was a stressed fermentation that took a few days to start, the barrels were in the way of brewing operations and needed to be moved into the tap house.  However, Wednesday morning it was learned that the concrete floors in that area do not slope to the floor drain and all of the foam pooled up and poured into the adjoining room; Marc's office.  While I imagine it smells wonderful, it will require quite a bit of clean up, and the barrels were moved back over the floor drain.  Reminds me of the mess I had with the pilot barrel!

Cider Keeve: Day 23

I checked in on the cider keeve last night.  I wanted to see how the fermentation was going.  As I mentioned in my earlier post, I am hoping for a slow fermentation that will, in theory, allow the Brett a chance to eat some of the sugars instead of the Sacchro dominating everything.

Upon looking at the carboy, I felt hopeful.  The head had kept at a soft dense foam.  I really don't have a lot of experience with fermenting cider, but it just seemed like the type of head that would result from a slow fermentation.  What has surprised me is the color of the cider.  It was so dark before, and now it is an almost vibrant orange color.

Keeved cider fermenting.

When I tested the gravity, I didn't know what to expect.  All I knew is that I was hoping for a high number indicating a slow fermentation and that the keeving process actually worked.  Today I came across this graph of gravity readings from keeved cider fermentations:

Lambourn Valley Cider

My gravity reading was 1.032.  Fantastic!  I am on track with other keeved ciders, so I now know I achieved a successful keeve.

When I think about the lambics I've done (1 and 2), they were at ~1.010 at the 2 month mark.  I anticipate this cider will be at about the same gravity.  The question is, what will the Brett have done in that time, and what, if anything, will it continue to do in this nutrient poor environment?

(Also, I plan to put some Drie Fonteinen dregs in there tonight to make sure there are stronger Brett strains than the Wyeast ones.)

Cider Keeve

I have been working with Leidel's Orchard up in La Cresent, MN.  They are looking into making hard cider, and after much discussion/research/brainstorming with the owners about the type of product they want to make, our pilot batches include a "Saison barrel", a "Natural barrel", and a "Keeve carboy".  I'll wait for another day to talk about the barrels, but I wanted to post a bit on the keeve batch.

Keeving is a old-world cider technique that has largely been forgotten, but is still done by some traditional cider makers in the UK and France. Simply put keeving releases natural pectin into the apple juice which then coagulates, removing much of the nutrients from the juice. As the yeast ferments the keeved juice, it uses the remaining nutrients, but runs out before it can ferment all of the sugar.  Traditionally, this has been done to create a naturally sweet cider.  For more information on the process, read this.

When I learned about this process and how it works, I thought about how lambic wort is brewed to have a lot of complex sugars that Saccharomyces can't eat, which leaves a portion of the sugars for the Brettanomyces.  I began to wonder if Brett would survive in a nutrient poor environment after the Saccharo died out.  So the purpose of this experiment is to see what will happen if I pitch lambic yeast into keeved cider.

However, this turned out to be a very difficult and laborious process.  I started with nearly 4 bushels (160lbs) of apples.  They had to be sent through a mill and the pulp left to sit for 24 hours (to release the pectin).  The next day we pressed the pulp, but our efficiency was about half that of a commercial cider press (and 10 times the work).  Leidel's Orchard actually spoke with a couple commercial presses keeving, but they were unable to do this process without a major rework of their set up.  I was hoping to get 8+ gallons, so I borrowed a friend's 12 gallon glass carboy to use as a keeving tank.  I only ended up with 6 gallons.

Then the keeving process starts.  The first step is to allow the pectin to coagulate in the cider.  Some modern additives help this process, but it is still a bit of an art.  The carboy was stored in my refrigerator for 10 days where it is cold enough to stall fermentation until the coagulated pectin gel has formed.

Most of the gel that formed fell to the bottom and is sitting on top of the sediment

The next step is to allow fermentation to start and the CO2 bubbles will lift the coagulated pectin to the surface making it possible to siphon out the juice in the middle.  I left it at room temperature for 5 days, which is much longer than I was told to expect, and only had a minimal amount of fermentation start.

Separation of cider and pectin gel.

Pectin gel pushed to the top by CO2 bubbles.

Only about half of the pectin gel was pushed to the top, while the rest stayed on the bottom of the jar.  I would have liked waiting until all of the pectin was pushed up, but I feared fermentation would accelerate too fast and I would be left with a cloudy cider.  Also, as the pectin gel at the top was exposed to the air, some mold was starting to grow.  I decided it was best to siphon at this point rather than risk ruining the whole batch.  As I siphoned, I also strained the keeved juice to capture any particles that might have been stirred up.

5 gallons of keeved cider with lambic blend yeast added.

In the end I was left with 5 gallons of clear, keeved, cider.  To that I added Wyeast Lambic Blend.  It will likely take 9-12 months before I know if the experiment worked, and if its anything like lambic, may take 2 years to really develop.  Apple cider is all simple sugars, and normally the Saccharo would out compete everything else.  My hope is that I've stripped out enough nutrients in this keeve to slow the Saccharo and allow the Brett/Pedio/Lacto to do their work in tandem.