Dry Ice amount in kettle sour

[DeanRIowa]

I am looking at doing a Berliner Weisse with the following process:

• Heat to Mash temps
• BIAB - Mash - 60 minutes, 90 minutes drier
• Boil 15 minutes, NO Hops
• Cool to 98
• Leave in boil pot
• pre-acidify wort to 4.5, phosphoric acid 1 mL at a time then test pH
• Transfer to primary - no aeration
• Pitch L. plantarum tablets(5)
• Add CO2 to fermentor(dry ice)
• Seal pot well
• Put heating pad around & seed warmer under pot
• Wait 1 - 3 days
• Check acid level, ph meter test, ph target 3.3-3.7
• ..........

How much dry ice should I use in my kettle(10 gallons) sour to purge the headspace of O2 and how many degrees will the dry ice drop my wort(6.25 gallons) in temperature?

1/8, 1/4, 1/2, 1 lb of dry ice? I have 2 lbs purchased.

thank you,
Dean

 

[RPh_Guy]

You'd be better of skipping the dry ice and the heating pads.

Cheers

 

[DeanRIowa]

You'd be better of skipping the dry ice and the heating pads.

Cheers

Why is that? I thought I needed to maintenance a temp in the 90s and purge the O2 from head of pot to help avoid infection?

thank you,
Dean

 

[gregkeller]

1 kg of dry ice should sublimate into enough gas to fill 0.54 cubic meters. Your 10 gallon brew kettle has a volume of about 0.04 cubic meters. So basically 100g of dry ice is more than enough to fill your entire kettle if it was empty. 50 g should be enough if the kettle is half full of wort. So I'd say anywhere between 1.75-3.5 ounces of dry ice is enough.
I'd go towards the lower end of that just to keep from cooling off my wort too much. Anything above what it takes to fill your headspace with CO2 is just gonna spill out the top of your kettle and do you no good.

 

[RPh_Guy]

Temperature:
Not all Lactobacilli species are the same. You need to look at the requirements of the specific species you are using.
L. plantarum sours very quickly in the 65-105°F range, so maintaining it at the upper end is not necessary.
I've seen several brewers that accidentally overheated their Lacto by using unregulated heating methods. You have been warned!

Dry ice:
Most is not considered food safe; is yours?
Plenty of anaerobes produce foul flavors/aromas (the bacteria in your bowels are anaerobes, for example), so removing oxygen is not a good solution to preventing contamination issues.
The other steps in your process are already more than enough to reduce contamination and prevent any contaminants from creating problems -- pre-boil, pre-acidify, pitch pure lab-grown Lacto, sanitize any equipment touching the wort, and seal the kettle.

 

[DeanRIowa]

Temperature:
Not all Lactobacilli species are the same. You need to look at the requirements of the specific species you are using.
L. plantarum sours very quickly in the 65-105°F range, so maintaining it at the upper end is not necessary.
I've seen several brewers that accidentally overheated their Lacto by using unregulated heating methods. You have been warned!

Dry ice:
Most is not considered food safe; is yours?
Plenty of anaerobes produce foul flavors/aromas (the bacteria in your bowels are anaerobes, for example), so removing oxygen is not a good solution to preventing contamination issues.
The other steps in your process are already more than enough to reduce contamination and prevent any contaminants from creating problems -- pre-boil, pre-acidify, pitch pure lab-grown Lacto, sanitize any equipment touching the wort, and seal the kettle.

Sounds great, I will not use the dry Ice.

I did borrow a temperature controller and heat wrap from a friend, is there an optimum temperature for L. plantarum(Swanson tablets), while kettle souring?

Thank you,
Dean

 

[RPh_Guy]

is there an optimum temperature for L. plantarum(Swanson tablets), while kettle souring?

It'll sour fastest up around 95-98F, although that may not be what you want if you intend to stop it before it hits bottom.
At that temp it'll finish around 3.0-3.3 probably within 24 hours assuming a good pitch rate.

Besides working somewhat faster/slower, the end result is the same regardless of temperature.

Cheers

 

[cactusgarrett]

I suggest leaving in the boil kettle to sour. It's been shown that purging of air (displacement with CO2) for the souring process isn't as beneficial as people perpetuate it to be, especially with plantarum.

 

[isomerization]

I have made about 50 gallons of quick sour beer, with no hint of off-flavors, using the following process:

1. Mash
2. Bring just to boil (don’t need long above 190F)
3. Chill to 100F
4. Rack to a plastic fermenter
5. Pitch ~1L Omega Lacto starter
6. Apply airlock
7. After 42-48 hr rack to kettle (I wrap a blanket around in winter, but this strain works great at room temp)
8. 20-30 min boil with additions depending on style
9. Chill and pitch yeast

The use of a fermenter keeps O2 out soooo much better than any approach in a kettle (imo).

EDIT: I will also add that overbuilding a Lacto starter has worked the same as with yeast, I’ve gone up to 6 month in the fridge with no issue (longer likely works too).

 

[RPh_Guy]

The use of a fermenter keeps O2 out soooo much better than any approach in a kettle (imo).

Let's see... What would we need to do to keep out oxygen?
1. Pre-purge an air-tight fermenter by pushing out sanitizer with CO2 pressure.
2. Continuously purge the kettle with CO2 while cooling (or use a measured amount of food-safe solid CO2 to cool) since the kettle will pull in air due to thermal contraction.
3. Do a closed, pressurized transfer into the fermenter so that air will get into the head space of neither the fermenter nor the kettle while transferring.
4. Somehow add the Lacto culture into the sealed fermenter without adding air (injection into a port with a syringe?)
5. Because the cooling fermenter will suck in air, we need to use a low PSI CO2 flow to maintain positive pressure in the fermenter during souring.
6. If we measure pH during this stage, push out a sample via CO2 pressure transfer.

It seems that avoiding oxygen is a practical impossibility or at least a logistical nightmare (think LoDO but worse since there's no yeast to help). ... No home brewer I've ever seen measures dissolved oxygen in the wort pre- or post-Lacto souring, so I believe people are kidding themselves if they think they're keeping out oxygen during a Lacto-only fermentation stage.

Plus, purging O2 doesn't necessarily fix other problems with the process that introduce or encourage contaminants.

Many home brewers and especially professional breweries use the kettle to Lacto sour, largely because of convenience (if you're killing the Lacto) but also because it works well.

Sorry for the rant. Cheers!

FYI the probiotic capsules I use for souring I've had in the fridge for over a year and they still work great.

 

[isomerization]

The answer to me is that using a pure culture, whether it be from a commercial pitch or capsule or etc., is the most likely source of successful quick souring (homebrew scale, not sure what professional scale has to do with this).

I could be way off base, but in my readings on the subject, oxygen exposure was the culprit for off flavors during kettle souring. The detailed approach worked for me, so I shared it.

Off topic, I do love this use of Cheers! on this forum, it comes off like a smiling middle finger lol

 

[Rob2010SS]

The answer to me is that using a pure culture, whether it be from a commercial pitch or capsule or etc., is the most likely source of successful quick souring (homebrew scale, not sure what professional scale has to do with this).

I could be way off base, but in my readings on the subject, oxygen exposure was the culprit for off flavors during kettle souring. The detailed approach worked for me, so I shared it.

Off topic, I do love this use of Cheers! on this forum, it comes off like a smiling middle finger lol

Ive done 5 kettle sours (not that this is a lot lol) and never worried about oxygen. Ive used the omega lacto every time. Ive never had any issues with off flavors. My process is as follows once mash is complete...

1. Chill wort to 95*F
2. Pre acidify to pH 4.4 with lactic acid
3. Pitch omega lacto
4. Cover top of kettle with saran wrap
5. Maintain temp of 80 to 95 by keeping kettle on stove
6. Once desired pH is hit, usually 3.2, proceed with boil as usual.

I think the worry about oxygen with kettle sours is made out to be worse than it is, in my opinion anyway. At least with the plantarum strain which is what i believe the omega lacto is

 

[RPh_Guy]

The answer to me is that using a pure culture, whether it be from a commercial pitch or capsule or etc., is the most likely source of successful quick souring (homebrew scale, not sure what professional scale has to do with this).
[...]
Off topic, I do love this use of Cheers! on this forum, it comes off like a smiling middle finger lol

I used cheers as something like "I mean no disrespect and I assume you're making quality brews, so let's toast to making good sours! It's all good!"

Agreed; it's a minor process difference. Just something to discuss.

 

[isomerization]

I used cheers as something like "I mean no disrespect and I assume you're making quality brews, so let's toast to making good sours! It's all good!"

Agreed; it's a minor process difference. Just something to discuss.

I don’t know why, but my brain always reads everything on the internet in the most sarcastic tone possible

How many probiotic capsules do you use per 5 gal batch? Just wondering for cost analysis, looks like they’re about $20/30 pills on Amazon.

 

[RPh_Guy]

I use one. The cheaper Swanson is fine too. I just use those because I could get them locally.

 

[isomerization]

I use one. The cheaper Swanson is fine too. I just use those because I could get them locally.

Wow! I was expecting 3-5 at least. So the 10 billion cells is enough to sour (I usually hit between 3.1 - 3.3 pH) in 48 hr? Do you keep the temp above RT? At that price it’s cheaper than the DME I use for a 1L starter, lol.

 

[RPh_Guy]

I don't know how many L. plantarum cells are in the Renew Life capsule I use (especially past the expiration date!). For larger batches I make a starter from one or two capsules.

There are a lot of different processes you could use, but bottom line is that if you want it sour fast, then use no hops, keep warm, and pitch lots of cells.

Buffering with chalk is absolutely critical with a Lacto starter, because Lacto growth is self-limiting from its acid production.
As small as a 100mL buffered starter is OK for a 5 gal batch, but 250-500mL will help it sour faster. 1000mL is overkill if you're achieving ideal growth rate.

Following recommendations demonstrated to produce ideal growth rate I add yeast nutrient, chalk, and corn sugar (I replace 20% of the DME with corn sugar) to my Lacto starters and let them sit at 70-75°F with occasional swirling for a few days to a week.

I also make other fast sours that aren't pre-soured, so for those I just use the wort as a starter (no DME needed), adding some nutrient, chalk, and one capsule, and pitching that a few days later when the yeast fermentation is well on its way.

 

[cactusgarrett]

How many probiotic capsules do you use per 5 gal batch?

When i use these (10 billion cells per cap, direct pitch into wort), the math comes out to ~1 capsule per gallon. This is the "no starter" approach, though, which I've found to be perfectly fine (and equivalent to when I do do a starter).