Why add new yeast before bottling a sour?

[JeffOYB]

I see that the Jeff Sparrow recipe for Flanders red says

"Bottle with new yeast and your desired amount of priming sugar."

So I should buy another packet of Wyeast and stir in before bottling?

Here's his article: https://byo.com/bock/item/655-flanders-red-ale

I see the other recipes in the same article don't mention a pre-bottling yeast, but they do talk about adding more yeast at various stages.

Is this an aspect where one might wing it and try add some Brett near bottling?

I like looking at all the recipes to see what they're juggling and how. Of course my result will vary from theirs. But I don't care... I kinda doubt it's a matter of drinkability...

 

[BGBC]

From the section of the article on bottling: "After many years of aging, use of a fresh yeast culture is essential."

 

[lumpher]

You'd want to add yeast for bottling because, by the time a sour is aged, the yeast is pretty much strained out and dead. You can add a neutral cheap yeast, like US-05 or even Munton's, to eat the bottling sugar and carbonate the beer. So yes, if you transfer to a bottling bucket and add sugar, also add your yeast then, and bottle normally.

 

[mitchard]

How much yeast is recommended per gallon?

 

[JeffOYB]

Thanks! Makes sense. I wonder about the line "after years of aging." That scares me! I know that sours can be aged a long time, but this will be my first and, uh, I'm hoping to get something interesting sooner than that. Might I expect to have anything drinkably close to expectations (if all goes well) in "only" 6 months? (Now I know what they say about getting a 'pipeline' going. Oh well!)

 

[LakesideBrewing]

I like to use a wine yeast for re yeasting before bottling. It performs well in an acidic environment.

Have you brewed this beer yet, or are you just looking ahead?

 

[sweetcell]

additional yeast is not required if you have brett in your sour. the brett will carbonate, it will just be slow - as in, it can take a month or more to carb. there is also a risk that the bugs eat up some of the priming sugar before the brett wakes up, and reduces how much sugar is converted to CO2. i have also had a few cases where the brett kicked up some cheerio flavor and needed to age out another 4-8 weeks to get rid of it (link, link). this is a rare occurrence, tho.

by adding a fast-acting sacch at bottling you're increasing your chances of a fast, predictable carbonation.

that being said, i have never had a problem carbing when depending only on the brett. then again i'm not in a hurry to carb, i tend to carb high (and use thick glass bottles) so i have wiggle room in case the level of carbonation isn't exactly as expected, etc. YMMV.

 

[mitchard]

So at 1.5 years or more, would the Brett still be viable enough (albeit slow) to carb the beer?

 

[sweetcell]

So at 1.5 years or more, would the Brett still be viable enough (albeit slow) to carb the beer?

yes, there is still brett in there. it'll be slow. if you want to speed things up, you can add more brett - or sacch. but it should carbonate on its own without any new bugs.

 

[JeffOYB]

I finally started making my first Flanders Red. I think I brewed and put it in the basement back in March, say. So 6 months ago. I recently sampled it and it tasted slightly tangy but very thin. Not bad but very little body. Red brown clear color. Last week I added 2 or 3 lbs of raspberries to it. I had to remove a couple pints to fit the berries in. I've left it all in the primary this whole time. 2" of white at the bottom. No pellicle. (I've posted about it elsewhere.) It's been almost a week with the raspberries (and 1-2 oz soaked oak chips). No bubbling. Should I just be patient or maybe it would help if I added some Monk's Cafe dregs to it? Would the dregs maybe add some live yeast and kickstart it? I'm not going to want to age this for a year or two. If I can get another fermentation going from the fresh berries then have that die out in a couple weeks if it tastes any better then I wouldn't mind bottling. Maybe the fermented berries will add more sour? I was also thinking of blending in my drinking glass w malty amber maybe to give more body. ?