The Power of Staged Fermentation - Sour Grapes

Progression of the beer from: Day of grape addition (left) to 4 months later in the glass (right)

I am a bit of an experimentalist at heart, and one area in which I do a lot of "experimental" brews is using the staged addition of pure cultures of wild or commercial yeasts & bugs, pitched at varying times, to produce unique sour beers that cannot be produced through conventional brewing techniques. I've made beers with similar complexity to classical sour beers using staged-addition of bugs, but that's not what this post is about. Rather, this post is about using these methods to make good beer from difficult ingredients. In this case, wild grapes.

Wild grapes are pretty common place across North America, and they come in two "flavours" - European wine grapes that have escaped the vineyard and native species of grapes. Wild European grapes are pretty similar to the grapes you buy in the grocery store, and can be used as would any other wine grape in sour beer brewing. Truly wild grapes are another beast. In fact, my first attempt to brew with these turned a rather lacklustre 2-year old golden sour into an unpalatable mess. Thankfully I only added grapes to one gallon of that beer, and rescued the rest with a more classical cherry addition! There have been attempts since, and none (until now) were worth writing about.

There are nearly 70 species of wild grapes native to North America, so I'm not sure how true the following statements will be for brewers in other regions of N. America (or elsewhere), but for people in Ontario and the north-eastern US, this should be relatively accurate. The three species of wild grape native to my area (Vitis riparia, V. aestivalis and V. labrusca) are quite different from their European cousins. These grapes are much more intense than their European cousins; while the juice of European varieties are generally used to make wine undiluted, our local wild grapes need to have their juice diluted between 1:2 and 1:5 to produce a wine with a tolerable taste. The grapes themselves are quite small (0.5 cm diameter or smaller), have a very thick and tannic skin, have a much higher malic acid content, and have a much larger seed portion (relative to the amount of fruit) compared to their European cousins. And it is those characteristics that make them hard to incorporate into sour beer - essentially, enough grapes to give a nice grape flavour also imparts a lot of tannins, malic acid and grape-seed character.

Tannins are astringent and drying, and while nice in small amounts, they can quickly become overwhelming and unpleasant. Indeed, tannins are often made by plants for the purpose of deterring animals from eating the plant - the term "tannin" comes from their ability to tan leather, so you can imagine how excess amounts make your mouth feel. Malic acid is also quite harsh - almost as harsh as acetic acid - and like tannins can be pleasant in small amounts but becomes harsh and overwhelming quite easily. The seeds of grapes are also problematic - they contain some earthy and woody flavours that are pleasant, but the high seed content of wild grapes means these characters can be somewhat strong, and in my experience, clash with brett phenolics.

My attempts at using these grapes in conventional sours failed because of these characteristics - the malic acid would make an already acidic beer far too acidic and harsh, the seed character would amp up the funk, which in turn clashed with the high levels of tannins. Even pressing the grapes for juice doesn't solve these issues (aside from the grape seed flavour) to any meaningful extent. But where traditional sour brewing methods failed, "experimental" methods succeeded.

More Below the Fold

One brew day - several sour(ish) beers

Random "helper" captured while preparing the fruit for this beer

This is a big post, providing information on three very different beers, all brewed from a single wort a little over a month ago. This has been (and continues to be) a pretty exciting series of beers - from a single wort I made a dry hopped berliner weiss, an experimental beer with the yeast Lachancea thermotolerans, and a fruited/bretted beer using wild grapes and the flora of those grapes!


At the heart of these three very different beers is an incredibly simple wort - a 44L (11.6 US gallon) batch of a no-boil Beliner Weisse, based loosely on the Milk the Funk Berliner Weisse recipe. Rather than post my recipe, I'd direct you to the previous link. The only modifications I made were in my procedures:

1. I mashed at 62.8C for 75 minutes, to get a drier final beer than the MTF standard recipe.
2. The wort was not boiled; instead I heated it to ~90C, and let it sit at this temperature for 10 minutes prior to cooling to 45C for pitching of the Lactobacillus.
3. No hops were used in the mash or boil.

Once the wort was prepared 4L was pulled off for the experimental Lachancea thermotolerans beer, the remaining 40L kettle-soured with a fantastic wild lactobacillus available only to my home brewing club, and once soured, split into two batches - one dry-hopped upon completion and the other bretted and fruited with wild grapes.

The details of each of these beers, and tasting notes for two of them, can be found below the fold. Its a bit of a read, so you may want to pull yourself a pint before you proceed.

Tasting Notes - Well There Gose Christmas

Picture doeen't do it justice; In the
right light the beer is medium-red,
and the head pink..

 A few weeks ago I blogged a recipe of a Christmas-themed Gose that I was brewing - flavoured with hibiscus, orange, cranberry and cinnamon, this was intended to be a unique Christmas beer for my winter enjoyment. So its time for some tasting notes.

I knocked this f***er out of the park. Hell, this may be the best kettle-soured beer I have ever produced.

Appearance: Red. The beer pours with a distinctive red coloured body; not the red of a melanoidin-rich barely based beer, but really really red. Crayon red. The wheat portion of the beer makes itself apparent in the haziness of the beer; combined with the red colour the effect is unexpected and visually pleasing - sadly, my shoddy camera work doesn't do it justice. The head itself is white with tinges of pink. Its highly carbonated, so the head pours thick and fine, and lasts for most of the pint.

Aroma: The cranberries dominate the aroma, with their unique sharp fruit character, along with a notable lactic aroma, shining through. Behind that is the sweet/berry aroma of hibiscus, a slight bready character, and a hint of yeastiness.

Belgian lace lasts right to the end

Flavour: This is where this beer shines. Up front is a bracing lactic sourness. The "tang" of the cranberry works alongside this, creating an overall "sourness" far more complex than what you normally get with a kettle sour, and yet retaining the clean sour profile that characterizes kettle soured beers. The hibiscus really acts to balanced this acidity through providing a sweet note - some sort of unfermentable glycoside, I assume - along with emboldening the fruit character provided by the cranberries. The orange plays a minor background role, giving a subtle orange-zest character noticeable mostly in the aftertaste. It took a number of test batches to dial-in the salt level to a level I like - and its perfect for this beer. The salt is present, but subtle. It acts more to tie the flavours together and to mellow the beer; the taste of salt is present, but mostly as a flinty character rather than an overt saltiness.

The only thing missing is the cinnamon. But given how wonderful the beer turned out, its absence is a blessing rather than a flaw.

Mouthfeel: Complex is the best description I can give. The beer was brewed to have a light body and be highly effervescent - and it is. The low finishing gravity combined with high carbonation and acidity creates a prickly, light mouthfeel on the tongue, especially as the beer enters the palate. But the salt works in opposition, rapidly adding a fuller, more meaty mouthfeel as the effervescence fades. The aftertaste is a mix of hibiscus sweetness/fruitiness, cranberry "tang" and lactic sourness, and fades in a way which leaves you wanting more.

Overall: If it isn't apparent already, this is a damned good beer. My second-best of the year (#1 to be blogged about soon), likely my best kettle-soured beer of all time, and in all honesty, one of the better sour beers that I've made recently. What it lacks in traditional sour-beer complexity is more than made up for by the interplay of the hibiscus, cranberry, acidity and salt. It is eminently drinkable, and yet, complex enough to be enjoyed slowly in front of a Christmas fire. There are four minor tweaks I would make upon re-brewing: 1) drop the cinnamon completely, 2) increase the hibiscus by 20-30%, 3) use the zest of an additional orange (3 instead of 2), and lastly, 4) brew a double, triple, or even quadruple sized batch. Because there's no way any of this beer will be left by Christmas!

Well, There Gose Christmas!

Nearly 2 months ago I blogged a teaser post on the brewing of my 2015 Christmas brew that would be entered into my home brew club's advent event, and given to my beer-loving family and friends.

This post is not about that beer.

Rather, this post is about another winter-holiday themed beer that is both a product of long planning (and fantasizing), plus a bit of last-minute brew-wizardry to make the brew-day happen. Sadly, I have no images of this last-minute brew, as I've recently taken a page from a fellow home-brewers book (hi, Devin!) and begun brewing late at night. Yep, 7 PM - midnight brew "days" do get you around all those irritating day-time things (jobs, family, friends, etc), but make for crappy photo-shooting conditions.

I wish I could claim this recipe as my own, and to some extent it is, but I received a lot of help on this one. The initial motivation for this beer is the table of Gose recipes by Cascade brewing in American Sour Beers; specifically, the all-to-brief mention of the winter gose featuring cinnamon, orange, hibiscus and cranberry. While a gose is a pretty straight-forward sour-ketteled beer, the balance of orange & hibiscus came from a very helpful set of  private messages and public posting of a similar gose recipe by BigPerm over at HomebrewTalk. The remaining balance of cinnamon, cranberry, hops and salt are from my previous brewing experiences with gose and those particular ingredients.

Despite that, there was (of course) a bump in the road. I had planned on souring using Lactobacillus isolated from a bottle of Hottenroth. Unfortunately, the lacto culture got "infected" with yeast (you know you're not a normal brewer when the yeast is the infection), so I was forced to preare a last-minute lacto starter using 1.040 wort @ pH 4.5, a handful of grain, and a "homebrewed" incubator to keep the cultures at 44C. The last-minute starter worked, so the brewday(s) was/were saved.

Additional details and recipe can be found below the fold.

Tasting Notes - Brett'd Sour Opprobrium

Enjoyed on the last
day of summer

Back in July I brewed a kettle-soured Berliner Weisse, which I split into two batches - one fermented straight with German Ale (Wyeast 1007), which was kegged and carbed within 10 days of brew day. The second half was fermented with the same yeast, but then underwent a secondary fermentation for ~2.5 months with a blend of Wyeast & White Lab's B. claussenii and Wyeast's B. lambicus. Those familiar with those brett strains will see that my goal was to add a nice fruit character to the beer, with a hint of funk.

The non-bretted version turned out pretty good - not quite as sour as I was hoping, but it was very quaffable. So what did the brett do to this beer?

Appearance: Its a Berliner - hazy (although not as hazy as the non-bretted version, likely because of its longer ageing), very pale in colour, and pours with a nice, long-lasting head.

Aroma: A tropical fruit character is apparent, as is a bit of lactic acidity. The bread notes of the unbretted portion are very muted - I don't think I'd notice they were present if I didn't know to look for them.

Flavour: The hoped-for fruit character has come through. The mix of bretts produced a nice fruitiness, although a specific fruit character has not been achieved. There's a bit of citrus and some stone fruit. In addition, a bit of leathery/earthy brett funk has emerged, giving this beer an additional interesting edge. Not only has the brett enhanced the flavour profile, but it also seems to have increased the acidity - I suspect this is an apparent change (rather than more actual acid), likely due to a lowering of the maltiness by the activity of the brett. The acidity balances nice with the fruit and funk, making for a wonderfully balanced beer.

Mouthfeel: Crisp, dry and acidic. Very refreshing. After taste is lactic with hints of fruit.

Overall: A huge improvement over the original - more apparent acidity, a more complex flavour profile, and a more pleasing mouthfeel. While the base recipe could use a little tweaking (in particular, a step-mash to get a more fermentable wort, replacement of some gravity with sugar, and a more aggressive Lactobacillus for the sour-ketteling), the addition of brett was a great way to improve on the beer. I've brewed bretted Berliners in the past, and while this one is not the best of them, it remains a very good beer.

Sour Opprobrium - Tasting Notes

An ideal summer afternoon - Berliner Weisse, tunes and
a magazine on the backyard deck.

So the Berliner Weisse that was a topic of a rather extensive post two weeks ago is kegged and carbed, meaning its time for a tasting!

This beer was a rapid sour, produced by souring pre-hopped wort in the kettle using a mix of commercial Lactobacilli. After 3.5 days of souring a 35C the wort was briefly boiled, hopped with Hallertauer, and fermented with German ale yeast (Wyeast 1007). 8 days after mashing in the beer was fermented and in the keg...it carb'd up last week while I was away at the cottage and is now ready to drink.

Appearance: Its a Berliner - cloudy, pale yellow-white, soap-like head. In a bit of a surprise, the head lasts a while; a rarity in acidic beers.

Aroma: A mix of wheaty/bread and lactic acid dominate the aroma, some "yeast" aroma is in the background.

Flavour: Lactic acid is upfront, alongside a sweet malt character. The usual breadiness of a Berliner is present, but not as strong as I'd prefer. Yeast character is somewhat neutral. The degree of acidity is lower than I expected - perhaps due to the higher than expected malt sweetness altering the balance.

Mouthfeel: Dry, but not quite as crisp as I'd prefer. After taste is slightly sweet and sour.

Overall: Given  the acidity of the wort prior to pitching the yeast (3.4) I'm surprised this isn't more sour - the sourness is on-style, but is on the weaker end and edges towards insufficiently sour. I think this is a result of my overly high efficiency on this batch - I normally aim to use sucrose for 10-15% of the fermentables, which guarantees a crisp finish. In this batch my higher-than-expected efficiency meant I could not add any sugar without seriously exceeding the alcohol range I was looking for. In fact I had to dilute the wort an extra 10% just to get it where I wanted.

So its a good beer, but not the beer I was hoping for; in place of a sharply sour and crispy dry beer I instead have a softly sour, slightly sweet beer. Its still refreshing, and on-style, but its on the opposite side of the style guidelines from what I was looking for. The good news is that the residual sweetness should work well with the Brett added to the other half of the batch; over the next month or so it should consume those dextrans, leaving a much drier beer with a more pleasing sour character.

Choosing the Right Probiotics for Souring Beer

A more-and-more common practice for quick sour beers is to use probiotic pills as a source of lactobacilli for the souring process. Indeed, the Milk the Funk Wiki has a growing list of alternate sources for these bacteria, including many probiotic capsules. A question that seems to rise quite often on this topic is "can I use probiotic brand X for souring beer". So here is a quick guide on figuring out whether a probiotic will work for souring beer.

In general, probiotic organisms fall into four categories when considering using them for souring:

1. Good choices
2. Probably don't matter
3. Avoid under some circumstances
4. Avoid at all cost

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Good Choices:

Bacteria that represent good choices are those which have the capacity to sour wort, and will do so with a minimal risk of off-flavours. These are solely species belonging to the Lactobacillus genus - i.e. Lactobacillus sp, where sp merely means "any species".  Lactobacillus plantarum and Lactobacillus rhamnosis are two of the more commonly seen probiotic strains, but any probiotic containing bacteria whose name starts with 'Lactobacillus' will work well.

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Probably Don't Matter:

Species which "probably don't matter" are those which are unlikely to grow in wort; either because the homebrewer lacks the ability to lower the oxygen level in the wort to the point where these organisms grow, or because wort isn't nutritionally compatible with these species. The flip side is that if these organisms grow, they should do the same thing as Lactobacillus - i.e. sour the wort while producing minimal off-flavours. So that's why they probably don't matter - they're not likely to do anything, but if they do end up doing something, they will help your wort sour. Included among these are:

1. Bifidobacteria sp. (again, sp means "any species")
2. Streptococcus thermophilus
3. Leuconostoc sp.

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Avoid Under Some Circumstances:

Only one group of organisms fall into this grouping - the Saccharomyces, as in species of yeast from the same genus of yeast that brewing yeast come from. At the time of this post the only Saccharomyces commonly seen in probiotics is Saccharomyces boulardii. Saccharomyces sp. fall into the "avoid under some circumstances" category as they will ferment sugars to form alcohol. You probably should avoid these - they will compete with Lactobacillus for sugars, and thus limit acidification. In addition, if you are planning on heating the wort after souring (to either pasteurizing or boiling temperatures), you will boil off the resulting alcohol leading to a beer with very little sugar left for the subsequent fermentation.

So as a rule you will want to avoid these, although it may be an interesting experiment to see what kind of beer you get if you pitch a Saccharomyces boulardii-containing probiotic mix into your fermenter.

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Avoid At All Cost:

The last group are those you want to keep as far away from your wort, beer and fermenter as possible. These are bacteria which can produce horrid off-flavours and ruin a beer. In this group there are currently three types used in probiotics, but this list may get longer in the future:

1. Clostridium sp. These guys can make butyric acid, which smells and tastes of a mix of parmesan cheese and vomit.
2. Enterococcus faecium. This bacteria can make bioactive amines, which some people are severely allergic to. Moreover, these amines are often quite unpleasant, and are what give shit and corpses (among other things) their unique odours.
3. Bacillus sp. (most often Bacillus ereus, clausii, and pumilus) make diacetyl (butter) and may also make bioactive amines.

Clearly, we don't want t be dumping any of the above guys in our beer!

EDIT/UPDATE: Stefan Wiswedel has done some experiments looking at probiotics containing amylases (which break down starches/dextrans) and protinases (which degrade proteins) along side the usual probiotic bacteria. Turns out using these is a bad idea - it kills the body and flavour of the resulting beer. Stefan has posted additional details in the comment section, below.

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A Simple Rule of Thumb

So that's a lot - but a good rule-of-thumb is to limit yourself to probiotics that contain only Lactobacillus species, which is easy to remember when you're at the store. 

But if your memory is better than mine, than any probiotic with Lactobacillus sp. plus any of Bifidobacteria sp., Streptococcus thermophilus or Leuconostoc sp. will be good as well.

And if the probiotic contains anything but the above 4 groups of organisms, I'd recommend you stay away.

How I Sour Mash...& A Recipe!

Wort, souring in the garage

I get the occasional request to explain how I sour-mash/sour-wort. So you ask, so you shall (eventually) receive!

Along with a description of my method - which is not all that unusual compared to methods others have published - I'm going to add in a few microbiology insights, some information on determining when you want to stop the souring process, and some other random hints & tips.

If you missed it, I also put up a post a few weeks ago about preparing lacto starters - a key thing you will need to do for a good sour mash/wort. Around the same time, 5-blades brewing put out a good post on harvesting wild lacto safely - a method I've used myself. Eureka Brewing also put up a post on optimized "media" for lactobacillus culture. I haven't tried Sam's media recipe, but its sound from a microbiology point-of-view. For a complete picture of the sour-mash/worting method I'd recommend reading this post alongside these other posts.

I've prepared this post alongside a brew-day, so I've include my standard Berliner Weiss recipe at the end. I love this recipe - simple and straight-forward, is great straight-up, but also works as a perfect base for fruited (lemon & cherry are excellent), s (coriander & salt = pseudo-gose), or bretted for a funk & fruit finish.  I am doing a split batch this time around, to make the most of the recipe.

Details, as always, can be found below the fold.

Lacto Starters

Starter wort, for the L. brevis and L.
buchneri to be used in my upcoming beer

Its almost time to brew a quick sour for the upcoming summer...which means that it is time to begin preparing starters of the lacto, sacch and brett going into the beer. Its been a few years since I blogged about brewing this kind of beer - a sour Berliner Weisse which can be ready in as little as 10 days - or which can act as the basis of more complex beers through the addition of Brettanomyces, fruit, herbs and blending with other beers.

But more on that later. Today's post is on a topic I get asked about with some regularity; namely, how to prepare a starter for Lactobacillus. A proper starter is especially important for sour worting, both to minimize the risk of infection by other bacteria, and also to ensure a reasonable souring time (a few days).

The good news is that lacto starters are easy - almost as easy as yeast, but you do need a bit more equipment.

For the starter you will need:

1. 1.040 starter wort (or apple juice, or MRS media)
2. Yeast nutrient (optional, but a good idea, especially if using apple juice)
3. A temperature controller
4. A heat source (I use a crock-pot)

As always, details are below the fold.

Easy as 1-2-3-4: a Rye Berliner Weiss

Last summer I prepared a fantastic sour-mashed Berliner Weiss. It was so good that I swore I'd brew at least 2 batches of it this summer, so its time to get going. But with a lot of changes. The last Berliner Weiss was as basic as you can get - 1:1 barley:wheat, sour mashed, and fermented with 1056. This year that is all going to change.

A big part of this change was motivated by a Berliner Weiss brewed by Justin, a fellow brewer in the London Homebrewers Guild. He used a bit of rye in his Berliner Weiss, and it worked incredibly well; the dry/crisp character of the rye fit in perfectly well with the sourness & dryness of the Berliner Weiss. The second big change I am making is the use of multiple yeast/bacterial cultures; instead of getting my lacto from a handful of uncrushed malt, I'm using an innoculum of lacto from my yeast bank (#91, Lactobacillus buchneri). I am doing this in the hope of avoiding some of the harsher bacterial tones I got last summer (likely from enterobacteria) - they eventually faded, but were unpleasant while they persisted. After boiling, I will be fermenting with a mix of Saccharomyces and Brettanomyces (yeast bank #111, 133 & 134) ; all three strains having been isolated from a commercial Berliner Weiss.

This unusual approach is also meant to deal with another issue - between starting the yeast cultures and the planned brew day - Saturday - SWIMBO and I decided to go camping. I'm hoping that the pitching of ~50ml of active lacto culture Tuesday night will sour things enough to finish the brew on Thursday...I'm hoping it will work, but either way this is the plan.

Why 1-2-3-4 you ask?  Its easy - 1:2:3 is the rye:wheat:pilsner malt ratio of the beer, and it took 4 microorganisms to ferment it out!

Recipe & Brewing Notes Below the Fold...

Easy Sour: Sour-Mash Berliner Weiss

Grain Bill: 50% Wheat Malt 50% Pils

This weeks beer is a wonderful summer beer that can go from mash tun to glass in as little as a week. This style is rarely found outside of Berlin, despite having a long-lasting reputation as the "champagne of the north"; an appellation provided by Napoleon's troops during their conquest of Germany.

Berliner Weiss (or Weisse) is a deceptively simple sour beer. Its key characteristic is a taste-forward sourness, provided by ample quantities of lactic acid. Low in alcohol, effervescent and dry, with a lactic acid pucker, this beer is great for hot days, patios & BBQs. Its intense sourness is not enjoyed by all, so it is commonly served with simple syrup (‘mit schuss’) or flavoured with either woodruff (‘waldmeister’) or raspberry (‘himbeer’) syrups. It is often considered the most refreshing style of beer.

Warming the mash water

Berliner Weiss recipes are simple; all start with a 50/50 mix of Pilsner and Wheat malts, and some add in a bit of table sugar to dry out the beer. Minimal hop flavour/aroma is provided by a light hopping with German hops. Starting gravities are typically 1.028 – 1.032, producing an alcohol content of 2.8-3.5%. From here the style can remain simple, or get quite complex. Lactic acid bacteria like lactobacillus or pediococcus are used to provide a strong dose of lactic acid, while neutral ale yeast ferment out the beer. Some feature a mild Brett character which adds a hint of fruitiness and funk to the beer.

There are two major ways Berliner Weiss can be brewed - a classical sour ferment, or a more modern sour mash. Sour ferments are the same as for Belgians sours: months-to-years in duration, complex, and unpredictable. Sour mashes are the polar opposite - and an excellent entry point for a brewer interested in sour beers. Instead of relying on souring organisms in the ferment, a sour mash instead introduces them into the mash. Over a few days the mash sours, after which the sparge and boil kill these organisms. The beer can then be fermented with a clean ale yeast, kegged, and be ready to drink in as little as 7 days after the mash is started.

As always, the meat is below the fold.