Cider Keeve: Day 270

We are just about at the 9 month mark from when I started the cider keeve experiment.  It was bottled at the 6 month mark and so has been conditioning in the bottle for the last 3 months.  As a recap, "keeving" is an old French cider making process that removes nutrients from the cider.  This results in a slow fermenting environment in which I applied lambic yeast/bacteria with the goal of emulating a typical lambic fermentation in cider, and it worked.

When I bottled the cider, I anticipated it would take up to 3 months to carbonate as that is common amongst lambics.  I opened a bottle after about a month and a half, and it was dead still.  Though slightly worried, I gave it some more time.  Last night, as we approach the 3 month mark, I opened a bottle to check on it. The cork was stubborn, but came out with a faint "psht".  No head formed as I poured the cider, but some bubbles did accumulate briefly on the side of my glass.

It is not nearly as carbonated as I would like, but nice to see something form.  I will continue to let this condition, but am thinking about how to correct this for next time.  The critical element in this cider is that there is a lack of nutrients.  While this is beneficial to getting saccharomyces and brettanomyces to ferment in tandem, at the point of bottling, I am afraid that there just isn't enough nutrients to properly carbonate the cider.  Next time I might try adding some yeast nutrients along with the priming sugar.

The cider is a very pretty color and crystal clean when poured in a glass. There is, however, some yeast sediment that accumulated at the bottom of the bottle during conditioning. Because of how crystal clear this is, I think the riddling and disgorging process of Champagne might make a nice finish.  Its a lot of work, but I might consider doing this on part or all of the next batch.

The plan as of now is to fill 2 barrels with keeved cider juice and ferment it the same way this batch was done.  Adding barrel aging and fermentation will certainly be beneficial, but this has to be one of the most labor intensive and expensive ciders to produce.  Custom pressing, risky keeving process, lambic-style fermentation, extended barrel aging, long bottle conditioning time, and possibly adding riddling/disgorging finish....yikes.  At least the final result is worth it!

Aroma:  Smells of apples and pears.  There is a brett funk that is subtle but definitely noticeable.

Appearance: Very attractive appearance.  Crystal clear with some bubbles forming ever so slightly.  I can imagine this would be beautiful with bubbles cascading up.

Taste:  Apple "juice" flavor is very mellow, but the apple skin tannin flavor is more pronounced.  I am pleasantly surprised with how tart it got. Earthy and musty flavors are the biggest contributions from the brett.  As I said earlier, I think Brett brux dominated the fermentation.  I used a Wyeast smack pack this time, but next time I will definitely be sourcing a lambic blend from East Coast Yeast and hope to have a more diverse brett presence.

Palate: Again, the carbonation is still low at this point, so it is not as effervescent as I targeted.  Aside from that, there is a great body on the cider.  It is light and fresh without feeling thin.

Overall: I am very happy with how balanced and funky this cider is.  I am thrilled that the experiment worked and look forward to making some slight refining shifts when we produce a lot more of this.  I think barrel aging will add a lot of complementing aroma and flavor characters, but even as is this is a very nice cider with a lot going on.  I'm looking forward to seeing how it continues to develop in the bottle.

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 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.

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.