So I tried making a homemade lacto culture over the weekend that I plan to use in a Berliner using the following method: -Brewed an all grain batch, boiled for 15min, and cooled -Placed ~5 tablespoons of spent grain in the carboy and pour on the wort at around 100F -I have been holding temp at around 105F and no action after 48 hours Based on other things I have read, I may have no committed enough to getting the lacto going before putting it on the wort. We are brewing in 1 week and I want to get this starter moving. The other caveat is I am out of town the end of the week on business so I have 2 days to get this going before I am out. I do have a White Labs 677, but I dont think that is going to give me the sourness I am looking for. Ideally I wanted to pitch this after the reaction was going a bit. I also have a buddy that has a sourdough lacto culture. Any idea if I could pitch some of that to get things moving? Please let me know if you guys have any ideas for me. And thanks for the help
My only thought is that spent grain might not have done the trick. Mash temperatures are not THAT far from pasteurization temperatures, so while I doubt the spent grain was completely free of bacteria, it may not have had the cell count you were going for. So if you have some extra malt lying around I would throw a few tablespoons of that in. Others on this forum can give you tips about encouraging lacto as opposed to less desirable bugs . . . I think adding some seltzer water and keeping oxygen out of the headspace might help? But I don't really know. If you are planning on pitching the White Labs 677 eventually either way, then I say go ahead and pitch it, by the way. Not sure what you would accomplish by waiting. And if you don't have any grain lying around, then sure, why not add your friend's sourdough lacto culture. Actually, that sounds great, I might even prefer that over the grain. But I have no experience with either one, so take my advice with a grain of salt.
I agree with the above comment. I'd also add that 105 isn't quite as warm as the ideal temp for lacto, something more around 115-120 would move things along a bit quicker. Definitely add some crushed grain as the spent grain is going to be less than ideal since the temp it was subjected to is going to have injured if not completely killed the native bugs. Finally, the sourdough starter should have plenty of lactic acid bacteria, but it is going to contain a lot of wild yeast that you may or want as well. Using grain and a higher incubation temperature is going to help select for bacteria rather than yeast if that is what you are going for.
Yeah I definitely need to crank up the temp. I added some bottle dredges from a couple of berliners last night. I am a little paranoid about the sourdough. I think it would be awesome to experiment with, but I could risk screwing up the whole thing.
Im gonna say that the "tried and true" method for culturing souring bacteria that is repeated here and on other HB sites isnt the best way to go about tackling this problem 1 - high temps are not necessary 2 - bad bacteria can and will grow 3 - other things like yeast grow as well 4 - o2 isnt as big of a concern as your lead to believe 5- pH in the starter is (buffering capacity) A good way to get a healthy culture, especially one that doesnt give any hot garbage/vomit/solvent flavors is to do this 1 - Start with a low grav wort (1020ish) 2 - add some grain + chalk 3 - ferment for a few days at room temp (65-75F) 4 - settle the culture, pour off the rest 5 - add new wort + chalk 6 - repeat steps 3-5 until the starter no longer smells off (1st on or 2 rounds might smell bad) This will ensure a good culture (no entero, etc) so you wont have any off smells, gets you a healthy culture of souring bacteria and yeast, and allows you to proof the yeast/bacteria in your starter for smell/taste before you use it A much more detailed instruction list and reasoning behind it is here
