Introduction for Pre-Primary Souring

I'm headed out to sea for a couple weeks of work and I wanted to get another blog post in before I go. This post is an introduction to one of my big projects for the next year of brewing - pre-primary souring. I've got one batch in bottles where I've used one of the approaches here but I'll have to wait until I come back to write up the brew day and give my tasting notes. This is pretty text heavy and picture poor, but I'll update it with pictures as I take more of these various approaches again with a camera around.

My goal with pre-primary souring in my homebrews is to get a controlled amount of tartness into  beers in the same sort of time frame as a typical primary fermentation. And also to not have live souring microorganisms in the fermentation and bottle. I am not try to make a quick sour beer or re-create the sort of fermentation profile you find in classic sour beers like flemish sours and lambics. And I am not trying to do 'pre-primary' sour in lieu of live souring during my primary (or in a secondary) fermentation. I think for beers you really want to be sour, putting in the time and letting the longer mixed fermentation will contribute more to the final flavor profiles you're looking for. Instead I'm interested in pre-primary souring to add lower levels of acidity to beer styles which I think would benefit from it. I'd like to get a controlled mild to moderate tarntess into certain beers like some of my saisons. In scenarios where I am really going for more of a sour character I may use this sort of approach to help out the microorganisms I want (as some microbes like Brettanomyces and Lactobacillus benefit from a lower initial pH), but when I am looking for a real acidic beer I'll stick with the long mixed fermentation of bacteria and yeasts and I feel that contributes to the flavor profiles I'm looking for in addition to the tartness.

So what do I mean by pre-primary souring? It is introducing some acidity to the beer before I begin my primary yeast driven fermentation. This can be achieved in a couple of ways, and the reason that I'm targeting souring before the primary is that it gives me the control I want. I'd like a more controllable/repeatable level of acidity as well as independent control of bitterness and acidity. If I were blending an acidic beer post-primary with a hoppy beer, I lose this control. The more acid beer I add, the less hoppy beer I get. But souring before my primary, and boiling (or re-boiling) the soured wort allows me to adjust the hop levels to what I want after the acidity is set. Some of the ways that you can do sour a beer before the primary are by adding lactic acid or acidulated malt, by sour mashing, or by 'sour worting'.

Adding lactic acid - I won't really cover this as I think it is pretty simple. Basically if I were going to add lactic acid for residual tartness (not mash pH) I would do it to taste after primary fermentation is done. This may influence yeast character as the yeast would be fermenting at normal pH rather than lowered pH (as is the case in all other methods below). Basically lactic acid is the most one dimensional approach and that's not really what I'm going for.

Adding acidulated malt - This is a step up from adding lactic acid in my mind. Maybe not a considerable step but I think there are some important differences. Although Weyermann doesn't give the details on their website, I believe the lactic acid character in acidulated malt is achieved by spraying the malt with lactic-fermented wort. Whatever the method, it is derived from natural lactic acid production by bacteria, meaning that any 'impurities' (other flavor compounds one might get from lactic acid bacteria) would also make their way onto the malt. Some of these may volatilize off in the boil, but it is still less pure than lactic acid. For simple tartness I lean this way as it doesn't take any extra time and requires only a minor amount of extra work over adding pure lactic acid (though I suppose you do lose a bit of control). Sourness form acidulated malt is pretty one dimensional but for achieving mild tartness I find it clean and pleasant.

Although I may add up toward about 10% (by weight) acidulated malt into a batch, I usually don't add more than about 6-8 oz (170-227 g) into a main mash for ~5 gallons/19L. I'll do my mash with this first bit of the acidulated malt and then add the remainder with about 15 minutes left in my mash when the bulk of my conversion is done so that I don't alter the pH drastically and affect conversion for my whole batch. With my water as it is and the salt additions I usually do, the first portion brings my pH to around 5.2 in a pale grist. I haven't measured pH after I add the second portion so I don't know if it would really affect conversion, but the method I use seems to work well for me. I find that I get fine conversion on the second portion added (I usually don't mash out hot enough to denature enzymes so the acidulated is converting for 15 minutes and then through my whole lauter and sparge). Adding 7-9% acidulated by weight seems to give some mild tartness, but not to the degree or complexity as one may achieve from the next two methods. Even so, this is the normal go to method I use for many beers at this point.

Sour Mashing - I've tried this approach and I liked in in the recipe for my saison named Soma and also another saison. The approach I took is detailed in the Soma recipe. Basically I did a small stovetop mash a day or two before brew day and then incubated it at 100-120 F (37.8-48.9 C) until I was running off my main mash, at which point I blended the sour portion back in. It is very important to keep out O2 in a sour mash, and dropping the initial pH a bit with acidulated malt and/or lactic acid helps select for the bacteria that you want. Sour mashing can give you the most complex flavor profile but that isn't always a good thing. It is the least controlled of these methods and the most difficult to do repeatably.

The remaining sour wort portion after most has been added to the kettle

'Sour worting'  - I first heard this term from the Mad Fermentationist (there's some info from him here and here). It is sort of taking an approach that one might find in Berliner weisse brewing process where pure lactic acid bacteria are added to wort without any Saccharomyces (or any type of yeast for that matter). From this point when the fermenting wort reaches the desired pH the wort can either be re-boiled, killing off the bacteria, or yeast can be added. This approach with blending back the souring portion into a boiling wort allows the most control as pH can readily be monitored and the blend volumes can be controlled well to lead to the beer you want. Blending in the boil also allows independent control of hoppyness (same for the above methods) as the souring is done, the bacteria are killed off and hops can be added to whatever degree you like (it is slightly more complicated than this, but I'll get to that later). It also has the added benefit of allowing you to leave a bit behind in a carboy which you can later top up with cooled wort, giving you a head start for a 'live' sour beer.

When I've taken this approach (for example in this saison) I made a bit of extra unhopped wort from a beer with a similar grist and pulled it off before hopping it. Then I pitched the lacto and waited until it was around where I wanted it before brewing the beer it would be blended into. This takes the luxury of a flexible brewing schedule, but if you are less flexible you can always wait longer and let it get more sour than you want and then use less of the sour wort to a similar final result.

Alright, so there's a quick rundown of approaches for adding acidity to a beer before a primary/yeast fermentation. When I get back from work at sea I'll write up my experience so far with the sour worting approach and get to work with some more trials.

Petite Saison Tasting Notes

The goal for my petite saison, as I talked about in the recipe and brewday post, was something like the excellent low gravity saisons I had in Belgian and northern France (Dupont's Biolegere and Thiriez/Jester King La Petite Princesse). I wanted something very light and refreshing around for the heat of summer and this beer matched that very well. Here are my tasting notes and any changes I might try to implement in future batches. There will definitely be future brew of this and I even have a re-brew of this beer currently fermenting.

Aroma:
There is a great fruity and floral yeast character (citrus and peach/apricot are most prominent, with some tropical fruit) typical of saisons. There is a very mild chalky/minerally character that I find in quite a few commercial saisons which I find pleasant in low levels such as it is here. There is some nice noble-type hop spicyness, possibly mixing with yeast phenols, which counters the floral/fruity character quite well. The yeast character really dominates the aroma and I don't get a whole lot of hop and malt coming through here.

Appearance:

A good white head, not as giant as in many other examples but certainly there and with good retention. Medium bubble size, but settles to a fine and pretty ~1cm mousse-like head. The color is hazy gold though I've had other pours that were pretty clear, so I probably didn't let this bottle settle enough.

Taste:
The fruityness is forward, with a bit more pear than the aroma suggests but still with citrus and peach as the most prominent fruits. There is a mild pleasant grainy character. The malt comes through surprisingly well for a beer with an OG this low, with a nice Vienna/pale Munich character in the finish. The hop bitterness balances the beer really well in the finish. Some milder spicy hop character supports the yeast well but the fruity yeast character dominates, with the malt coming through a bit stronger than the hops. As the beer warms the hops come up in the balance and the malt goes back. The aftertaste is refreshingly dry hop spicy and grainy malt, leaving a crisp finish and inviting another sip. And another, and another...

Mouthfeel:
Creamy light body with high carbonation and a pleasant crisp finish. This is exactly what I was going for in this beer. It is super refreshing and very dry. It seems fuller than the final gravity (1.001) would suggest, which I suspect is due to glycerol (which I discuss here and mention here). This is a compound that adds to the body of a beer which yeasts produce during fermentation, and saison yeasts like the ones I used in this batch produce more than typical.

Overall and Thoughts:
I am really happy with how this came out. It matches almost all of what I wanted, and exceeded my expectations a bit in the malt character. It's dry, light, and super drinkable but with surprising body, which is appropriately light without being too thin, and has surprising malt character. It is comparatively easy to make a low OG beer hoppy (as hops are independent of beer strength), but getting sufficient yeast character when the yeast aren't fermenting much sugar, and especially getting enough malt character when the malt levels are by necessity lower, can be tricky. Even more so for the malt when the final gravity is so low as it is in this beer. So I am really happy with how this malt came across. As I detailed in the recipe post, I used mostly malt produced by a local maltster including a light pils (1.5 L) and a light Munich (6.5 L). If you don't have comparable malts available I would use the palest Munich you can find and maybe substitute 25-50% with Vienna malt to replace the 6.5 L light Munich I used in this recipe. Another pils of the more standard ~1.7 L should be ok for the pils substitution, but I do think some nice grainy character might be coming from using a slightly lighter malt. But that's probably what I'll do in the future when I don't have any more of these specific malts around.

Other than that I don't really think I'd change much. My target was for a beer that was a fair bit lower in strength but through a combination of about 3-4 extra points in the OG and a couple points lower in the FG my ABV is 4.0% instead of the 3.0-3.5% (preferably closer to 3.0 %) of my target. I may try to drop the strength of this recipe down in the future but I am a bit torn about it because I am quite happy with this batch. Either I'll go back to the drawing board on a saison around 4-4.5% and drop this recipe down a bit, or I'll create a whole new recipe for a lower gravity saison and keep this about where it is (or maybe a touch stronger). I suppose I'm leaning toward the first option here to differentiate this recipe more from my average strength, pale, relatively hop forward saison recipe of around 6.5% that I am happy with. But we'll see.

Belgian Single Tasting Notes

I often find that I have a lot of individual bottles of beer (homebrew and commercial beer) sitting around waiting for some occasion where I can give them the focus I want. Consequently, I always turn to my recent batches of homebrew for a beer I can enjoy without as much focus. This has the downside of putting off a review, but I like that it gives me some opportunities to think more passively about the beer and come up with some ideas before sitting down to the full review. And often times I find that although the beer may be carbonated after a week or two, it benefits from a bit more conditioning/mellowing time and some previously rough characteristics may have softened more. I find that especially true with many of my saisons, and many of the leading commercial Belgian/French saison brewers have a bit more extended aging time, either in bulk or in bottles, after the fermentation is complete. Anyway, I've finally gotten around to taking some tasting notes on the Belgian single I bottled about a month ago.

Aroma: Very strong noble-type and other European hop presence, the hops smell a bit like hop drops candy (or a really fresh bag of European hops) in the intensity as well as the profile. The Styrian Goldings seem to come through stronger than the Saaz. Yeast character is relatively restrained but there is a nice fruity character with pear and mellower citrus like blood orange. There is a bit of clean crisp malt in the background but overall hops dominate the aroma and yeast lends a nice milder support.

Appearance: Dark gold, fine haze (the haze in the image is mostly condensation), large rocky white head with fine bubbles. The head retention is pretty impressive and a thick lace is left. The appearance was pretty much my ideal for this type of beer.

Taste: Strong hop character, which dominates the overall flavor profile. Great forward noble and spicy/earthy hop flavor, moderate/high bitterness (but appropriate for the balance). There is a bit of vegetal/leafy matter in the finish, the sort of thing one might get from too many hops/too much contact with hops. A nice mild fermentation fruity and floral character (mostly pear with some citrus as well) and no bubblegum or banana (which I was happy about). As the beer warms the fermentation character becomes more apparent. Overall this is assertive for it's strength and well on track to what I was going for.

Mouthfeel: High fine carbonation and a light crisp body. Perhaps the final gravity could come up a couple of points or I could try in some other way to increase the body a small amount (my FG was 1.005, which was a bit lower than my target). But as it is, it is pretty refreshing and I like that. There is a small amount of astringency/plantyness in the finish.

Overall Impression/Future changes:This is pretty nice overall. my main complaint would be the plantyness of it. That plantyness isn't too strong, but as it is something I don't want there at all, I'dd like to try to not get it in the next batch. For the next batch I think I'll try to drop the hop load a bit and maybe also drop the total IBUs. I may also shift a small amount of hops to earlier in the boil to serve as more of a classic bitterness addition. I approached this with more of a North American 'hop bursting' type brewing process and I am reasonably sure that this is not what is being done at the breweries making this sort of beer in Belgium. I'll also try to do a better job of keeping hops out of the carboy while transferring out of my boil kettle. I think in beers where I may be pushing limits when it comes to having a vegetative taste come through (especially when the rest of the beer is relatively delicate and fermentation temps might be elevated) keeping carry-over hops out of the primary becomes especially important.

The malt characteristics are good for this in that the malt is light and crisp and lets the hops really shine. I think maybe I'd like a bit more fermentation character, but not much. It is really easy with Belgian styles of beer to overdo it on the fermentation. Especially when bubblegum and banana esters start to develop (which I generally try to avoid/limit in Belgian beers). I'm happy with the fermentation character I got (and happy to miss many of the characters I didn't get) so I won't manipulate fermentation temperature too much. Also, as the beer ages more in the bottles I am noticing the fermentation profile come more forward in the balance.

A couple days after writing these notes I got the chance to have a nice commercial example of this style from the US - Russian River's Redemption. My quick comparative notes from that are that at first Redemption seems much lighter on the hops. And while that is true, Redemption is still appropriately hoppy (maybe not as hoppy as the Westmalle Extra or the Westvleteren Blonde), the refined nature of Redemption's hop profile makes it seem less hop forward. The other main difference is that Redemption has a stronger fermentation/yeast profile. I'd like my next batch to fall a bit in the middle of the two in regard to yeast profile intensity.