beer not sour enough. Would like to add Lacto

[Brandt]

Made a Belgian Dark Strong almost two years ago. Racked 5 gallons in a keg, and have been enjoying it this whole time. Even won a silver medal in a homebrew comp with it.

About 18 months ago I added Brett. Claussenii to the remaining 5 gallons, and waited for the pelicle to fall. I sampled it recently, and it has definitely changed, and dried out some, but I really wish it were more tart. So I would like to add some Lacto to the carboy. I have not taken a gravity reading, but I don't taste much sweetness, and I feel like it has definitely stopped fermenting. I highly doubt the Sacch. yeast I used (WLP530) is still active after all this time.

In order to get some tartness, should I now add some sugar along with the lacto? What kind of sugar?

Thanks!

[sweetcell]

In order to get some tartness, should I now add some sugar along with the lacto? What kind of sugar?

if you use a sugar that is unfermentable by sacch - like malto-dextrine (MD) - you won't have to worry about the sacch munching it. another approach is to get starches into the brew, for example by boiling some oats and adding the resulting liquor.

your beer has a lot of alcohol (presumably, because it's a BDSA) so most commercial lacto strains aren't going to do very well in there. you might not get any flavor impact from them at all. instead, I would add the dregs of sour beers. those hardier bugs will sour up your beer. Cascade & Jolly Pumpkin dregs will sour up just about anything.

[Ozwald]

Start with a gravity reading. There might be enough residuals in there for the bugs to munch on. If not, I would suggest long-chain sugars & a very healthy pitch of bugs to compete with the brett.

[Brandt]

all good ideas! I didn't think about the starch. I do have some WL Sour Mix I could throw in there instead of the Lacto culture. I've had great luck with throwing in Oravl dregs into under-attenuated beers, but they weren't as high gravity as this BDS.

I'll check the gravity first, then try the oatmeal trick if I need to. Thanks!