I wish to report my results using the
Lactobacillus Plantarum (
LP) co-pitch method of souring described
here.
Summary: It works! I tried co-pitching in several different settings and each time it produced a pleasant souring effect in 2ish+ days. You will need to learn from experience how much souring at fermentation equates with how much sourness in the finished beer but overall this is a quick and natural way to get sourness into the equation. And that’s the bottom line, you can skip the rest of the stuff below which just repeats this in detail and get to souring!
Biases, sources, and conflicts: I’m lazy, cheap, and curious. Really like
bretted beer (BB) and
bretted melomels. Like
bretted sour beer (BSA) and sour beer (SB). I’ve included
bretted dry-hopped melomels (BDHM) here because they are an easy way to get to a
bretted, moderately sour, highly carbonated, highly alcoholic beverage that tastes great and the process is very similar to making a
bretted beer. Since my pH meter long ago fell into disuse and I want to avoid the whole pH/TA/perception scrum I will use “baseline” (think average non-sour beer), “slightly sour” (think apple juice, pH 3.8ish, more TA), “moderately sour” (think pineapple juice, pH 3.5ish, more TA), “very sour” (think your fav most sour beer, pH 3.2ish, even more TA) and “acidic” (think vinegar or straight cranberry juice, pH 2.2ish, lots of TA). Using your taste buds only to perceive an increase in TA as the wort/must ferments (with the decrease in sugars and the ostensible increase in lactic acid) should appropriately be viewed with skepticism.
LP was from Swanson in capsules, which were pulled apart and sprinkled on top of the wort/must.
Brettanomyces Bruxellensis (
BB) was a scion of OYL-212.
Saccharomyces cerevisiae (
SC) was Hornindal OYL-091, the current house yeast.
Results co-pitching LP with BB and SC in melomels: This may seem off topic but from the fermentation vessel on, the process is very similar whether you are working with wort or a fruit juice and honey must. I tried this first with a store bought pasteurized apple juice. I had a
BB/
SC yeast cake already going when I first read this
article. Knowing that AJ usually produced only a slightly sour BDHM I wanted to see how this process would help push this into the moderately sour category. I added juice and 0.7 lbs of honey per gallon of AJ to the yeast cake with two capsules of
LP. I sampled the fermenting must every 12 hours or so. At 48 hours the melomel was clearly more sour than the original juice. At 60 hours it reached what I thought was a solid moderately sour character and transferred it to a keg with 2 ounces of cascade whole hops and a small dextrose charge. I also filled and capped 2 bottles that I have since sampled to judge the sour level and still think it is decidedly more sour than the baseline juice would have been.
Next up I tried this with store bought pasteurized pineapple juice. From past experience I know this will produce a solid, moderately sour BDHM but wanted to see if I could push it into the very sour category. Onto the
BB/
SC/
LP yeast cake went juice, 0.4 lbs honey per gallon and 1 capsule of
LP. Thought about not using that capsule to see if there was viable
LP in the yeast cake but decided I would try that later. Serial tasting of the fermentation revealed a sour must/melomel, but in the malodorous milieu of
BB and declining sugar levels it was unclear if it was decidedly more sour than expected. Measuring TA before and after would have been helpful. This was kegged and dry-hopped in the keg at 72 hours and will be compared to other non-
LP pineapple BDHM in the future.
Results co-pitching LP and SC in beer: First up a straight sour. 75% pilsner, 25% malted wheat, no hops, very short boil, onto Hornindal, 2 caps
LP. Decidedly sour at 56 hours then hop tea and small dry-hop charge added to primary. Kegged at 12 days with dextrose and small dry-hop charge.
LP produced a nice, clean moderate sour in only 2ish+ days. At 4 weeks in the keg, this is a solid sour, slightly too sour for my tastes and the grain bill/amount of dry-hops.
Results co-pitching LP with BB and SC in beer: Next up a BSA. 60% pilsner 25% malted wheat 10% cane sugar 5% Vienna, no hops, short boil, onto Hornindal/
BB yeast cake with 2 caps
LP. Was clearly sour at 48 hours and dry-hops/hop tea added at that point. Left in primary 3 more weeks with dry hops and just recently kegged with small dextrose charge. Too early to assess the overall beer but the
LP clearly and swiftly soured it.
Discussion: Using
LP resulted in a rapid and pleasant tasting souring effect. Going forward, I will likely use
LP in all apple BDHM and some other juice/fruit BDHM. Pineapple, grape, and grape blends bring enough acid to the party for a great BDHM so I will likely not use it there except on rare occasion. Will also use this for future SB and BSA. Will need to learn how the level of perceived sourness in fermenting and finished beer compare. Cheers