I've been thinking about a lot of the material out there from Chad Yakobson over the last few months, and one thing he constantly emphasizes is that if you understand how brett works, you can exert some control over beers brewed with it by modifying your techniques and ingredients based on your desired final result.
There's some good information out there about ways to do this. For instance, this set of slides distills a lot of the information from Chad's dissertation, and has some great stuff about pitching rates and acidifying the wort, as well as things he's talked about elsewhere like using adjuncts to improve the final mouthfeel of brett beers.
But there's still a lot I'm unclear on, and I think it would be very useful to understand it better. I'm particularly interested in how ingredient choice and brewing techniques can affect final flavours.
One thing he mentions is deliberately increasing levels of precursors for various flavour compounds in the wort. So, for instance, if you want the spicy/smokey/phenolic characteristics associated with 4‐vinylguiacol and 4‐ethylguaicol, you can do a protein rest to increase ferulic acid levels in the wort (as you do with wheat beers). If you want to minimize these flavours, then there are other things he mentions you can do to minimize their precursors.
In the same vein, you could try to increase the levels of other acids that are precursors to various esters. In his Sunday Session interview, Chad talks about a beer that had high levels of caprylic acid, and jokes that he got a lot of stick for it because that's an unpleasant, goaty flavour, but he knew that the brett in the beer would eventually convert it to much more desirable flavours.
So, anyway, my point is that there isn't much information about other ways to control levels of these precursors, particularly fatty acids, in your wort. I was looking over Oldsock's blog the other day, and he talks about using buckwheat in an attempt to increase caprylic acid levels (here and here). This didn't seem to work for him, but I wonder if one might have better luck by combining such ingredients with particular mash schedules or something similar (as above with ferulic acid).
I'm still researching all of this, and I haven't put any of it into practice yet. But I thought it might be helpful to have a thread here to discuss these kind of techniques, especially as others might have more experience or more knowledge of the chemistry behind wort production.
There's some good information out there about ways to do this. For instance, this set of slides distills a lot of the information from Chad's dissertation, and has some great stuff about pitching rates and acidifying the wort, as well as things he's talked about elsewhere like using adjuncts to improve the final mouthfeel of brett beers.
But there's still a lot I'm unclear on, and I think it would be very useful to understand it better. I'm particularly interested in how ingredient choice and brewing techniques can affect final flavours.
One thing he mentions is deliberately increasing levels of precursors for various flavour compounds in the wort. So, for instance, if you want the spicy/smokey/phenolic characteristics associated with 4‐vinylguiacol and 4‐ethylguaicol, you can do a protein rest to increase ferulic acid levels in the wort (as you do with wheat beers). If you want to minimize these flavours, then there are other things he mentions you can do to minimize their precursors.
In the same vein, you could try to increase the levels of other acids that are precursors to various esters. In his Sunday Session interview, Chad talks about a beer that had high levels of caprylic acid, and jokes that he got a lot of stick for it because that's an unpleasant, goaty flavour, but he knew that the brett in the beer would eventually convert it to much more desirable flavours.
So, anyway, my point is that there isn't much information about other ways to control levels of these precursors, particularly fatty acids, in your wort. I was looking over Oldsock's blog the other day, and he talks about using buckwheat in an attempt to increase caprylic acid levels (here and here). This didn't seem to work for him, but I wonder if one might have better luck by combining such ingredients with particular mash schedules or something similar (as above with ferulic acid).
I'm still researching all of this, and I haven't put any of it into practice yet. But I thought it might be helpful to have a thread here to discuss these kind of techniques, especially as others might have more experience or more knowledge of the chemistry behind wort production.
