Probiotics, Bacteria Starters, No-Boil, Hop Teas, and more - my first co-pitched Gose

[FatDragon]

It's not fuzzy or hairy. It looks more like a pellicle than mold to me, but I guess it could be non-fuzzy mold? I'm skeptical that mold could be growing on the surface of a beer that's over 4% alcohol. What's the minimum ABV to stave off mold?

When I inserted a straw into the fermenter, chunks of the pellicle stuck to the straw like little cottage cheese curds, if that helps identify it.

Either way, acetone... Is it worth tasting at this point, or even safe to do so?

 

[RPh_Guy]

The photo could go either way but if it's not fuzzy like mold, it's not mold. If it's not mold, it's safe to taste.

Acetone smell (actually ethyl acetate) won't go away with time. Pichia, Brett, and other wild microbes produce it when there's too much oxygen exposure.
Like vinegar, it's always a risk with wild fermentations. The last bottle of Petrus Aged Pale I bought tasted like nail polish remover

Bummer.

 

[deeve007]

These are co pitched with yeast rather than kettle soured. I'm going to give them a couple more weeks and if that doesn't do it, I'll probably just dose with lactic acid to my desired sourness and call it a day.

@FatDragon I had a similar response on the "Milk The Funk" group re fermenting for just a couple of weeks with co-pitching, so not sure if they simply don't understand co-pitching versus kettle souring, or if I've got incorrect advice.

How long did you leave it in the fermenter in total before bottling, and how did it turn out in the end?

 

[RPh_Guy]

I co-sour and post-sour lots of beer with L. plantarum. They sour over a few days.

For example I recently co-pitched bacteria and US-05 in a gose and let it ferment at 66-68°F (19-20°C). It was sour and done fermenting after 5 days so I added hop tea and bottled. The beer was fantastic.

 

[deeve007]

So it seems as with so many things brewing, there is more than one way to brew a sour...

 

[RPh_Guy]

Souring methods!

LAB fast sours:

• Sour mash, where the mash is soured instead of the wort.
• Pre-souring and then killing the bacteria (Kettle sour), with or without pre-boil.
• Pre-souring without killing the bacteria, with or without pre-boil.
• Co-souring (pitch Lacto and yeast at the same time)
• Post-souring (pitch yeast first and then Lacto after a day or more)

Cheater fast sours:

• Directly add lactic acid or other acid.
• Use an absurd amount of acidulated malt or other acidic substance.

Other fast sour:

• Use a yeast that produced lactic acid (Lactic acid yeast)

Sours with Brett:

• Everything co-pitched (traditional method).
• Brett & bacteria pitched after primary.
• Brett delayed pitched into any of the fast sour methods above.
• Co-pitch Sacc and Brett, delay pitch the bacteria (post-sour with Brett).
• Brett-only fast sour (no Sacc) with any of the fast sour methods above.

.... Think I covered everything.

 

[deeve007]

• Co-souring (pitch Lacto and yeast at the same time)
• Post-souring (pitch yeast first and then Lacto after a day or more)

What would be the difference flavour/sour wise with these two? And any other differences with regards to the rest of the process?

 

[cactusgarrett]

We should just lobby to have RPh make a stickied post, since i'm pretty sure he touts this daily.

 

[RPh_Guy]

Acidity mutes yeast expression.
Therefore post-souring increases the yeast expression.

For example when I want to use a flavorful yeast like kveik or WLP644 (an excellent choice by the way), I use a post-sour process:
Use some chilled wort from the batch to make a Lacto starter.
Pitch the yeast, let it ferment for 1-2 days
Add the bacteria.

It still sours before fermentation finishes and the yeast produced all of its esters before the pH dropped.

We should just lobby to have RPh make a stickied post, since i'm pretty sure he touts this daily.

Haha, perhaps. I don't mind helping on an individual basis, but maybe that could help too.

 

[deeve007]

We should just lobby to have RPh make a stickied post, since i'm pretty sure he touts this daily.

I would LOVE a sour sticky with some of this core info in it, especially when you have people from "other" forums saying otherwise, just point them to the one location, "There ya go..."

 

[FatDragon]

How long did you leave it in the fermenter in total before bottling, and how did it turn out in the end?

Infected - it smelled like acetone. See above, haha!

The follow-up Gose that got a short boil is quite nice, though. I did bump up the acidity on the way into the bottling bucket with a few mL of lactic acid on that one. I've also got another small sour wheat on the yeast cake from that Gose. I'm thinking I might add some Brett at bottling on that one just for fun.

 

[Gnomebrewer]

Souring methods!

.... Think I covered everything.

Nope. You missed spontaneous ferments!

 

[RPh_Guy]

It's true I didn't cover different ways of sourcing the microbes (e.g. dregs, spontaneous, wild starters, etc), hopping methods, AG vs extract, or blending .... But as far as pitching schedule I hope I got everything.

I consider spontaneous to be included in the Brett beer category "everything pitched at once". Whether there's actually going to be Brett in there is uncertain, but you treat it the same. Most/all commercial producers that use spontaneous microbes also pitch a Brett culture at the same time.

 

[Gnomebrewer]

Infected - it smelled like acetone. See above, haha!

From a quick google search, it looks like Lactobacillus can produce acetone, so maybe it wasn't contaminated, just had too much oxygen exposure. Just because it can produce acetone though, doesn't mean it's likely to in beer - so maybe your beer was contaminated with something like acetobacter. The question there is, 'is Lactobacillus likely to produce acetone in the presence of oxygen in beer'? Brett certainly can.