Monday, 25 May 2015

Brewing Saisons: Some Thoughts on Process

I've brewed a lot of beers since April, most of them saisons, but as the temperatures start to get hotter and the school year wraps up, I'm starting to think about stopping brewing for the summer.  This is partly because I'll be going back to England for a month, but also because brewing in a hot and humid apartment is just not much fun.  I'm sure I'll fit in a couple of batches, but the next proper series of beers I have planned will be the top-ups for my soleras in preparation for a blending project at the start of the Autumn.

I'll probably find time to post here occasionally---I need to write tasting notes for a number of batches---but I'll be updating this blog's Facebook page more often than I write posts here.  I'm hoping I'll find time to go through some more old brewing texts, and I'll post anything interesting I find on that page.

Rather than write up brew day posts for the saisons I've been making recently, I thought I'd write a post summarizing some of the changes I've made in my brewing process during this most recent round of saisons.  This isn't supposed to be a general overview of saison brewing---for that, I can't think of a better guide than this post at Spontaneous Funk---but rather a summary of some of the changes I've made that might be of interest to anyone trying to brew lower gravity saisons (many commercial versions come in at 6% ABV or higher, whereas I aim for 4-5% ABV).  I'll come back to these points as I write tasting notes this summer, and try to see what kind of effect they have on the final products.  When I start brewing again after the summer, I'll be focusing more closely on water chemistry and pH during my brew day process, which will probably lead to a few more changes.

1. Carbonation

I'll start with one of the more obvious ones: aiming for a higher level of carbonation, somewhere around 3 volumes.  This probably seems obvious to anyone whose drank a lot of commercial saisons, since many if not most have fairly spritzy carbonation.  But the truth is, I didn't really start brewing these beers in emulation of commercial versions.  Instead I was captivated by Yvan de Baets' description of historical saisons in his essay in Farmhouse Ales, and set about trying to brew the kinds of beer he described.  My frame of reference was therefore a bit limited: I knew I liked Saison Dupont, but I hadn't tried many other Belgian versions beyond the beers from De La Senne and De Ranke, and I didn't like the bigger American saisons I'd had at that time.  This meant I took my starting point from the bitter, low alcohol English beers I'd been brewing up to that point (part of what intigued me in Yvan's essay was that the beers he described seemed to combine the best parts of bitter, with the complexities of lambic), and that meant aiming for a lower volume of CO2 in order to prevent the beer from seeming harsh and thin.

I still tend to prefer lower levels of carbonation in most beers, but after drinking many more Belgian saisons I want to try to capture the striking appearance these beers have when they're poured, with those thick moussey heads rising inches above the glass.  Higher levels of carbonation seem essential to acheiving this, so I'm going to aim for at least 3 volumes of CO2 for a while to see how I like the results.  (This is a little inconvenient as I don't have enough heavy bottles in rotation to package every beer, even after a recent group buy for champagne bottles.)

2. Cereal Mash With Unmalted Adjuncts

These next two points follow on from the last.  Higher carbonation risks making the beers seem harsh and sharp, at least to my palate, especially when dealing with the low alcohol saisons I like to brew.  My thought is that one way around this might be to include large volumes of unmalted grains in the grist to provide some mouthfeel and body.  Saison lore has it that farmers would use whatever unmalted grains they had available in their beers, and as I've mentioned before I usually have grains like spelt on hand for baking bread (I've started buying buckwheat explicitly for brewing, but I'll probably try baking with it soon as well).

Most of these grains require a cereal mash, which is a bit of a nuisance and certainly lengthens my brew day.  I could probably achieve something of the same affect by using flaked adjuncts like wheat and oats, but this would limit the grains I could use, and I also wonder whether the unmalted grains don't make a more distinctive flavour combination than their malted or flaked counterparts.  I love the savoury smells you get from a cereal mash with spelt or buckwheat, and I'm hoping some of that will come across in my beers (as I think it does in commercial beers like Saison D'Epeautre or Duchessic).

3.  Step Mash With Protein Rest

In his article on brewing saisons, Joe Stange suggested that including a protein rest and using undermodified malts might be key to achieving the thick head characteristic of beers like Saison Dupont.  I've been roughly following the schedule described in Farmhouse Ales, with protein rests at 113 and 131 (I often skip the first one), and then longer rests in the mid 140s and 150s. Since I'm doing a cereal mash anyway, its pretty easy to use this hot porridge to speed up the transition between steps, and the adjuncts should provide plenty of extra protein.  (I suspect that ideally the adjuncts should be in the main mash for the protein rest, whereas its more convenient for me to add them back to the main mash to get from the low 130s to the 140s.  I've tried both ways, and I'll try to note any obvious difference in the results).

4. Oak and Fermentation

This is another idea to improve the mouthfeel and overall flavour profile of my beers, inspired largely by listening this this old interview with Shea Comfort, in which he talks very knowledgeably about the uses of oak in fermentation.  One big takeaway is that judicious use of oak can improve the structure of a beer, rounding out and accentuating certain elements of its flavour profile, while also prolonging its life-span.  Comfort talks about different ways of using oak cubes, but the one that caught my attention was adding them for primary fermentation.  This seems to lead to a more subtle contribution, as many of the compounds associated with oak (vanillin in particular) are processed by the yeast during primary fermentation.  The hosts of the show taste three of Shea's beers in the final segment, the first of which is a Belgian beer fermented in  with oak cubes in the primary, and everyone seemed to agree that the contribution of the oak was very subtle, to the point where you might not even realize it had been used (unless you recognized its other effects).  This sounds like exactly what I'm looking for, and also echoes some comments I've heard certain brewers make on The Sour Hour about the contribution barrels make to their beer (i.e. that its not about tasting oak).

For now I've started experimenting by adding between 10-15 grams of freshly boiled oak cubes to the wort along with the pitch of yeast (only in one beer so far---hopefully in another if I find time to brew this week).  I'll see how I like these results, and if it works well I may start doing this regularly with most of my saison-style beers.

5. Yeast Blends and Cell Counts

I've covered this already in an earlier post.  Unfortunately two of those beers spent a bit too long in primary fermenters that allow in a lot of oxygen, and they may both have unacceptable levels of acetic acid.  I'll make that call in the next few weeks.  But I used one of the blends in several beers, so I'll have the opportunity for some comparison.  Since I'm probably done brewing for the next few months I might not get a chance to use them again, but if I like the results it won't be too hard to recreate them.

One thing that's come out of making these blends is that I'm gradually getting more comfortable with using my microscope to perform cell counts.  I did this for the last few saisons that I brewed, using the calculator at Mr. Malty to get an ideal pitching rate and then measuring out the requisite amount of each slurry after performing a cell count.  One thing that was striking here was how little slurry I needed, relative to what I'd been pitching before,  Overpitching isn't the worst thing you can do to a beer, but it may have had an effect on the way the yeast expressed itself, so I'm curious to see what difference this has.

Friday, 8 May 2015

Saison Yeast Blends

As anticipated, after a vigorous start to fermentation my saison brewed with the Wyeast version of the Dupoint strain stalled at around 1.030, and has been slowly attenuating further ever since.  I'm in no rush, so I'm happy to leave it for another few weeks until the yeast drop out of suspension.  If its not dry enough at that point, I'll add some brettanomyces and let it age for another few months, but based on other people's experience with the strain I don't think that will be necessary.

All of this made me even keener to try out my own yeast blends, using the Dupont strain along with other organisms.  It seems that people generally agree that the 'leaven' at the Dupont brewery consists of a number of different strains (including wild yeast), and I've read plenty of interviews with U.S. brewers who like to use the Dupont strain for its flavour profile, but pitched along with another strain to ensure a fast and reliable fermentation.

So I knew I was going to make a blend of at least two yeast strains.  The question now was what I should pitch along with the Wyeast Dupont strain.  Wyeast French Saison strain (3711) seems to be the most common choice here, since it ferments quickly and produces a very dry beer, albeit with some residual mouthfeel due to its high glycerol production.  I've pretty much sworn off using this strain because I don't really like its flavour profile (which means I don't like a lot of American saisons!).  Perhaps it would express itself differently as a small proportion of a blend, but since I already had a pitch of Wyeast 3726 on the go, I decided to use that instead.  This is reportedly a version of the Blaugies strain, which in turn is supposed to originate from the Dupont brewery.  All the more reason to use it in the blend then, especially since it reliably attenuates my saisons to within a few points of 1.000, and produces a flavour profile I quite enjoy.

I settled fairly arbitrarily on a blend of 70% Dupont to 30% Blaugies.  My thought was that this would be a large enough proportion of Dupont that it would dominate the flavour profile, but with enough Blaugies that it also contributed some complexity along with taking over in the second half of the fermentation and ensuring the beer dried out in a reasonably short time frame.

Both yeasts came from the cakes of recent saisons.  I got out my copy of Yeast, along with a microscope that I purchased second-hand thanks to a fellow brewer who runs one of the labs on campus, and had a go at serial dilution and yeast counting to work out how many cells I had per ml in each cake.  I'm not completely confident in my procedure here, so I won't write it up (I followed the instructions in the book, diluting the yeast by a factor of 1000, counting the number of cells I could see on a hemocytometer, then working from here to a number of cells per ml).  Based on these numbers I measured out three pitches of roughly 100 billion cells, a slight overpitch given that each was going to be 12 litres of 1.040 wort, but I hadn't taken the viability of the cakes into account in my original calculations, and I figured it would be better to overpitch than underpitch.  Interestingly enough the final blends contained smaller slurries than I usually pitch, which means I've been overpitching by a significant factor for a while now.  I got a quick start to fermentation, which suggests I didn't mess up the count too much, so as I become comfortable with this process I'm going to use it more frequently to determine the volume of yeast I re-pitch.  (Incidentally, you don't need a microscope to come up with your own blends: check out Dave Janssen's procedure here.)

So now I had three pitches consisting of 70% Dupont and 30% Blaugies.  But what about the 'wild yeast' the Yvan de Baets says Dupont keeps in their leaven to ensure complexity?  The Wyeast 3726 has been through several generations in my saison equipment (i.e. scratched up buckets that have had plenty of brettanomyces in them), so there's a good chance its already not a pure culture.  I decided to keep one pitch as it was, with just these two strains.  For the second, I added about 20ml from a fermenting starter of the recently released Wyeast Brettanomyces Clausenii; and for the third, I added half a vial of The Yeast Bay's Amalgamation blend.

Three pitches, three saisons.  If I were a proper blogger I'd probably have pitched each blend into an identical beer to compare the results, but its not easy to make enough beer to make that worthwhile on my set up, and I wanted some variety anyway.  Instead I compromised, brewing three beers with the same grist but using different hops in each one.  The grist was mainly pilsner with a little bit of golden promise and malted wheat, aiming for an O.G. in the low 1.040s.  I picked the hops fairly arbitrarily based on how I imagined the final beers tasting, in each case going for a 2:1 blend for everything except the bittering addition (60, 20, 5, 0 minutes).  Here's what I ended up with:

Dupont/Blaugies saison: blend of Crystal and Sterling.

Dupont/Blaugies/Brett. C. Saison: blend of East Kent Goldings and First Gold.

Dupont/Blaugies/Amalgamation Saison: blend of Huell Melon and Hallertau Blanc.

I brewed all three batches last weekend, keeping each beer below 70 for the first 12 hours of fermentation and then allowing them to rise from there.  I haven't taken any measurements, but fermentation started quickly and each beer has been more active than the saison pitched with Dupont alone.  I'll rack them to secondaries over the next few weeks (all my carboys are tied up at the moment), and at that point I'll take measurements and make decisions about bottling timeframes.  I'm hoping to get them packaged in the next month or so, so that they can condition while J and I take a trip back to the U.K.  So, expect tasting notes in a few months!

I'm hoping to repitch each blend at least once as well: it will depend on (a) how each beer tastes when I rack it, and (b) how much brewing I get done before we leave.  Right now I'm thinking I'll use the Amalgamation blend in a version of my Buckwheat Saison (and cut it with the final gallon from my first pull of the Roeselare Solera); split the Brett. C. cake between a bitter spelt saison and a saison fermented with LAB along with the blend; and use the Dupont/Blaugies cake in a petite saison made with wheat and/or spelt (a 'grisette', if you insist).

Saturday, 2 May 2015

Spontaneous Fermentation II: Success?

After my failed attempt at spontaneous fermentation in November, I was itching all winter long to have another go once the snow left and the temperatures rose above freezing.  It took a little longer than I anticipated (Chicago winters don't give up without a fight), but at the start of April I finally had another chance to have a try at it.  My process was essentially the same as last time: I let the wort cool by an open window overnight, and then transferred it to a carboy along with an oak spiral that had been sitting in a gallon jug containing my 'house culture'.  There were at least three significant differences that might have affected the outcome this time round: the oak spiral had been sitting in the culture for several months, instead of for a few weeks; the temperatures overnight stayed well above freezing; and I was able to give the wort an extra hour or two to cool, though it was still in the high 70s when I transferred it the next day.

Last time the wort sat for almost ten days without showing any signs of a strong fermentation.  A thin white pellicle formed after a few days, and remained there for the next week, but when I finally took a sample the gravity had barely dropped at all, and the pH was still dangerously high at 4.9.

This time, after only two days, a thin krausen formed on top of the wort.  Within a day or so, this was more than an inch thick, composed largely of small fine bubbles that looked like bubble bath (the second photo is from day five).  The krausen stuck around for a while, dissipating briefly, then flaring up again a few days later.  At this point the aromas coming from the airlock were slightly vegetal and gross, after seeming fairly clean for the first few days.

Eventually, once things had settled down a bit (approximately two and a half weeks after fermentation started), I transferred the wort to a smaller carboy and took some measurements.  The pH was at 3.96, and the gravity at 1.022, so I knew it should be safe to try a sample.  To my surprise, it didn't taste that bad!  Slightly tart, with a predominantly doughy character and some vegetal notes.  Not something I'd enjoy drinking in any great quantity, but also not something I wanted to spit out at once.  I count that as a success.

Transferring the beer to a secondary provoked another round of fermentation, which has continued up till today (a month after I brewed it).  I don't want to take enough wort for another gravity sample, but I did sneak another taste.  The vegetal aroma is still there, and the taste is a strange combination of slight tartness, sweetness, and bitterness from the aged hops.  I expect this to change significantly as it ages, and at this point I'm planning on essentially forgetting about it for the next year (who am I kidding, I'll probably sample again before then, but I'm going to at least try to leave this one alone).