I'm currently working out the numbers for an oud bruin, and I need some advice on the microbes I should pitch alongside my sacch. strain. I want some residual sugars after fermentation, so my knee jerk reaction was only use a blend of lacto strains to get the desired souring, but in my experience this gives a boring, one-note sourness. To get sour complexity, I add pedio, but then you need to get rid of the eps and diacetyl. To do that, you generally need a brett strain to clean all everything up, BUT if I add a brett strain its going to chew through any hope I have of residual sugars. Also, brett keeps any nasty autolysis byproducts out of the finished product with extended aging. So, my questions are: 1) Should I just suck it up and only use a lacto blend to sour the beer? 2) If I add pedio, is there any chance of removing the EPS and diacetyl without pitching a brett strain? 3) Should I be concerned with autolysis off flavors without brett? 4) Are there any brett strains you all are familiar with that would leave a FG of at least 1.01, even after extended bottle conditioning? Apparently GY150 will only achieve 80% attenuation, but I have no experience with this strain.
LOTS of questions to be answered here. First of all, are you wanting to make a traditional Oud Bruin or just a dark, malt forward sour beer? What are your sensory goals for this beer? What does your recipe look like? Those answers should give us a good direction.
Here are some more direct answers: You can, if you like, but lactobacillus sp. are notoriously hop intolerant, so take that into consideration when crafting your recipe. Pedio will reduce its own EPS and any active yeast, including sacch. sp, will metabolize the diacetyl. Short answer: no Long answer: depends upon how long you're planning on aging this beer Any B. anomalus strain will do this, as they are poor fermenters of maltose, so if you use a sacch. cerv. strain as well, you won't get the hyper-attenuation that is so common with B. brux strains.
It's not quite going to be traditional, since that would involve blending old and new batches, and I'm notoriously bad at blending. As far as sensory, i want it to be dark, since fruit forward with some malt sweetness and a rounded, full mouth acidity. Think RR Consecration with a little more malt backbone. Grain bill is a Munich base with 60 and 120 Crystal malts and Amber candi syrup for the flavors. 10-15 IBU for bittering; I've had good experience with lacto at these amounts as long as you pitch enough bacteria. I like to age my sours on the primary yeast cake for 2-4 months with a small initial dose of oak; I like the compounds that result from a long primary with oak added during the main fermentation. Then I will rack onto more oak for extended aging with an inert gas overlay until it's ready (typically another 6-8 months). The extended primary is where I'm worried about the autolysis.
If you've had good experience with certain cultures, then go for it. Me? If my IBUs were that high I'd pitch P. damnosis. I would not worry about it at that length of time.
