I tasted several from several batches of sours today. All had a butyric acid thing going (or else the first one I sampled overwhelmed my palate and I am suffering from palate fatigue). Is there a way to ferment with Brett to not produce butyric acid? Is it all going to go away (i.e., become pineapply ethyl butyrate, I think) if I am patient? These are not finished beers. 1. Half lacto-kettle soured wheat beer, half brown ale wort, with WY Brett lambicus 5526 pitch added to the blended wort. SG 1.010 2. Half lacto-kettle sourced wheat beer, half brown ale wort, with WL Brett clausenii 645 pitch added to the blend. SG 1.004 3, Half kettled soured wheat, half maibock wort already fermented with S-189, with WL Brett lambicus 653 added to blend. #3 has the least sour and least butyric. #1 has the most butyric, SG 1. 010. Except for the maibock half of wort 3, none have been around for more than a couple months, so more time may be in order. However, I was operating with the thought that Brett in the absence of sacc would finish a beer in approximately the same time frame.
To me the source of that flavor wasnt the WY packs it was the kettle souring, I think that is one of the worst ways to go about souring, you never know what type of flavors you will get, sometimes its ok but far too often you get that hot garbage/vomit smell/taste I prefer to build up a wild culture and preferentially select the good guys by dropping the pH of the wort pre-fermentation in a starter and then do a couple step ups to remove the bad guys
Nope, it is absolutely the Bett. [see edit]. I shoud have clarified that I did not use grain to inoculate the kettle, I used the WY lacto strain, inoculating cool, boiled wort. I tasted the kettle soured beer after souring, and then boiled it to bring souring to a halt. It could have been a Berliner. I pitched the Brett upon cooling. [edit] Just read that butyric is a product of anaerobic bacteria. I am faced with the possibility of infecting all three batches? Or misidentifying the cheesiness I am getting as butyric acid.
it is not inconceivable that you had some bad bacteria somewhere on your equipment (tubing, kettle, mashtun, etc, etc) that contaminated the batch. It doesn't take much butyrate to ruin something, i think the odor threshold is something like 1-5 ppbv, it also doesnt take a whole lot of time for those bacteria to proliferate
Brett turns butyric acid into pineapple esters given enough time. Check out Chad Yakobson's brett experiments.
Yes, this is the hope, but I am bummed. My reason for taking the approach I did, to use a commercial souring agent and kill it off with a boil was intended, in part, to avoid the cheesy flavors that can develop from using the microflora associated with grains to inoculate wort. It is ironic that I took these efforts and may have subsequently contaminated all three batches. I haven't had an uncontrolled infection in the brewhouse in over 150 batches. I'm thinking I may give up brewing with Brett, if it will let me...too many unsatisfying experiences.
What was the PH when you added the Brett. I'll also be using 5526 soon and read it should be under 4.5.
Didn't measure but it was sour. Most lagers have a final pH of 4.2-4.6. This was much more sour like Berliner Weiss added to an equal volume of wort. If you average an equal volume of pH 3.5 with 5.5, you end up with something like 3.8. I would guess I was much lower than 4.5.
Chesse flavors and smell is usually isovaleric acid. Butyric acid smells more like vomit. http://www.milkthefunk.com/wiki/Isovaleric_Acid
