I've got two separate 5 gallon carboys of sours that I brewed in February and March of 2013 still in the back of my closet. One has been on peaches for a little over a year. The airlocks have never gone dry, and both still smell and taste pretty damn good. Any worry of problems with them or should I just go ahead and bottle. I'm assuming i'll need to add a bit of yeast to both to get them to carbonate properly, any other things to consider? I meant to get them bottled ages ago, but time just got away from me.
I would say as long as there is no mold or anything like that you should be fine. You will def need to add some yeast at bottling. Cheers and I hope its fantastic
Thanks for the response. I figured it would be fine, but wanted to check just in case, especially the one on fruit. I've used champagne yeast for this before, i'll probably do that again. No sign of mold or anything funny other than the pellicle that came on fairly quickly and and looks about the same at this point. I'll give an update once I get my first taste in a month or two.
Wouldn't recommend what you've done to others, but if they smell and taste fine, you should be fine as well. Here's a little reading on re-yeasting: http://www.milkthefunk.com/wiki/Packaging#Re-yeasting
Particulars to consider when trying to carbonate a sour beer that is that old include really low levels of CO2 in solution (compared to a beer that's only a month or so old) and the ability of whatever yeast you intend to pitch in what is likely a low pH beer. Everyone's favorite piece of information on re-yeasting and bottle conditioning sour beer is a paper by Dr. Matthew Bochman in the journal Food Microbiology; essentially, they conclude the best way to ensure healthy refermentation is to pre-adapt your yeast to the acidic conditions by growing them for ~24 h in a 1:1 mixture of the given sour beer and YPD (yeast peptone dextrose, a lab growth media--using a 1.020 malt extract starter would be fine) and then cold crashing and using that yeast for bottling. Ensures the yeast will be able to handle the low pH environment.
Terminal acid shock is certainly a good thing to take into consideration when reyeasting. It is covered in the link that I provided above, but here's a little article about it as well. http://archive.news.indiana.edu/releases/iu/2016/03/sour-craft-beer-study.shtml
Since the idea is to pre adapt the yeast to conditions they'll see in the sour beer to be carbonated (i.e. low pH and dextrose as the food), why would a 1.020 malt extract starter be a good substitute for YPD? The two are not really similar at all. The sugars in Malt extract are mostly not dextrose. The sugar in YPD is 100% dextrose. Disclaimer: I haven't read the paper, but I'm guessing there's a reason the guy specified YPD rather than some maltose rich medium.
