Crushed Oyster Shells For pH Buffering - Best Practises?

[zed255]

With the exception of my very first fermentation destined for distillation I have been using crushed oyster shells to act as a pH buffer. I have always noted that I got most of my shells back out at the end of the fermentation even though pH has been measured at about 4.0, and sometimes dipping into the high 3.x range. Never had a crash or any fermentation issues as of yet due to pH being too low, but doing reading here got me to thinking that I'm not using them most effectively. I note the shells being added to the ferment end up at the very bottom, of course due to their density, entrained in the trub. They are not exposed to the liquid of the wash and ultimately not able to do the job for which they were included. Anyone else using crushed shells recovering most of them from the trub too? Makes sense to me after seeing it occur through several ferments now but haven't found much mention of this issue.

This time I decided to take a different approach. I put down a wash yesterday and I have hung the quantity of crushed oyster shells in mesh strainers approximately mid depth of the wash. I will monitor their rate of consumption and the pH of the wash to see if this offers better results. Anyone else doing similar already and have some experience to relay?

Some seem to prefer whole shells and some are getting good results with small slabs of marble, both of which would present themselves more readily to the wash and I suspect be more effective.

[shadylane]

Keep us posted on your experiment

[OtisT]

I use whole shells. I started out just tosssing them into the wash when I pitch, and after I switched to using mesh bags hanging in the clear beer section of the ferment. My reason for switching to the bag was so that I did not have to fish shells out of my grains before squeezing or otherwise risking a tear in my big grain bag.

I’ve not measured differences, but now that you bring this up I do think there is a slight difference in the two methods. Its just anecdotal, but I do believe I go through shells faster since I started hanging them. I get maybe two/three full uses with the mesh and maybe three/four uses w/o.

Otis

[bluefish_dist]

I found they did not dissolve fast enough to stop a ph crash. I now use calcium carbonate powder. It is more usable.

[Kareltje]

I sometimes use egg shells, but never measured the consumption of them. Or the effect on pH.

[acfixer69]

A clam shell wind chime rig hanging in the the barrel sound the go in a UJ style generation wash.

AC

[zed255]

A little over 24 hours has elapsed.

OG was 1.077 and is now 1.32, good active ferment going on. I usually get to 1.00 in 72 hours and completely dry in about 5 days. This progress looks normal.

The pH read 3.6 and the shells I put in appear to be half gone already. You can actually see extra effervescence where the shells are hanging. Not sure I trust my cheap pH meter but I am reading 4.00 on the 4.00 calibration solution, so is my acidity that great?

[jb-texshine]

If you will check the recovered shells you will notice that they are...chalky... maybe wrong word for something thAt wet but the best descriptor. They will also have lost weight it you track that. Even if in the turn. Keep in mind that it's the yeast producing the acids anyway. A mesh bag is handy though.
I now use a big lump of dead coral reef from a pet store with a string tied to it. Coral is composed of mainly calcium carbonate with some magnesium and trace minerals. Can't go wrong there.
Keep us posted.
Jb

[greggn]

I use a tea strainer to keep the oyster shells contained ... easy to lift out at the end of a ferment even without the chain which I discarded at the start. Since I generally do not ferment on the grain it also keeps the shells above the trub (at least until the very end of fermentation once the yeast flocculate).

Even though I primarily do AG, with only the occasional sugarwash, I toss it into every ferment since it's easy. Under those circumstances shell consumption is low.

The photo below is from morebeer.com but the same strainer is sold by multiple bog box stores.

[Shine0n]

Normally I'll ferment with an open top and use a 2x4 with a paint strainer bag tied to suspend the shells half way in the wash/mash and cover with a towel or loose lid.

I don't record loss and weight it's just noticeable after a few ferments, I rinse them off after and place them in a gallon zip lock bag after drying them.

jb, I like the coral idea!

I'm a cheap man so I'll look for the best and easiest way possible to achieve my goal.

[fizzix]

Normally I'll ferment with an open top and use a 2x4 with a paint strainer bag tied to suspend the shells half way in the wash/mash and cover with a towel or loose lid.

I don't record loss and weight it's just noticeable after a few ferments, I rinse them off after and place them in a gallon zip lock bag after drying them.

jb, I like the coral idea!

I'm a cheap man so I'll look for the best and easiest way possible to achieve my goal.

Ditto ShineOn's method except I use a sealed lid. The shells definitely deteriorate and I just refresh them when low. No crashes yet.

[shadylane]

I now use a big lump of dead coral reef from a pet store with a string tied to it. Coral is composed of mainly calcium carbonate with some magnesium and trace minerals.
Jb

The crushed oyster shells I get from the feed store, also contains crushed coral.

[jb-texshine]

I now use a big lump of dead coral reef from a pet store with a string tied to it. Coral is composed of mainly calcium carbonate with some magnesium and trace minerals.
Jb

The crushed oyster shells I get from the feed store, also contains crushed coral.

Shady,I think you may have been the one that pointed out the makeup of coral to me to start with.

[shadylane]

Here's what I use. A double hand full in 15 gallons of sugar wash.
It won't restart a stuck ferment, but it'll keep it from crashing

https://www.amazon.com/Manna-Pro-Oyster ... ster+shell" onclick="window.open(this.href);return false;" rel="nofollow

[StillerBoy]

I found they did not dissolve fast enough to stop a ph crash. I now use calcium carbonate powder. It is more usable.

From my experience, I am in agreement with bluefish.. it does help some, such that the ph will not drop as fast, but I still use calcium carbonate to maintain the ph at a 4.5, otherwise it drops to low.. and I have tried to position the shells just about everywhere, with not different in the behaviour of the ph..

Mars

[Bushman]

I use a 5² ph stablizer. It's expensive but seems to last a long time and I have not had to take any measurements, leaves no off flavors, and it's easy to use (one tablespoon per 5 gallons).
PS, it's available at brew supply stores.

[zed255]

This wash is holding at a pH of 3.6, according to my meter, and still roiling. Looks like perhaps a little more shell is gone, but hard to tell visually. In the future I will have to take accurate weights to see. Still notable effervescence at the surface above the location of the packet of crushed shells.

The SG yesterday was 1.032 and today it is 1.008, which is continuing like the clockwork I've been accustomed to. I expect tomorrow it will dip just below 1.000 and slow down.

I've never before taken any real measurements of pH but got curious as some have suggested they have had crashes due to low pH, particularly with sugarheads. I have not had any fermentation issues with the exception of allowing one to cool too much (cold spell in the local weather a while back, my basement cooled off more than expected) that adding some heat took care of.

[zed255]

OK, so the ferment SG has as predicted gotten below 1.000 and is at about 0.996. It still looks pretty active though as I can see particulate moving about as if riding convection currents (and that is likely what it is). Still nice and warm so I expect this one to finish nice and dry.

The wash pH is up a little to 3.8 and I'm still getting a plume of effervescence above the packet of shells. Whether this is them dissolving or just off-gassing due to the shells surface offering nucleation sites I do not know. Either way the pH is climbing.

[zed255]

Activity is slowing as expected, SG is now 0.992 and the wash is dropping in temperature. I have upped the setting on a small oil filled heater 'tented' with my fermenters. I will add supplementary heat for a couple days to accelerate the final phase of fermentation, per my usual practise.

The pH has continued to climb, now at 4.1 and there is still a plume of effervescence coming off the crushed oyster shells.

[zed255]

If anyone is reading, I recon fermentation is complete. SG is <0.990 (my hydrometer scale only goes to 0.990) and the pH is about 4.1.

Upon removing my packets of shells it looks like there is much more left than I initially thought. Looks like I simply did not do a good job dividing them evenly. Almost nothing was used.

Perhaps next time i will spread them out more by putting SS screen 'panels' with the shells sandwiched inside. Considering they appear to have brought the pH up from 3.6 to 4.1 as the fermentation wound down I believe they may be doing some buffering but might not be as effective as I was thinking.

[dieselduo]

I use a dry hop spider for the shells

[fizzix]

Hop Spider's a great idea, dieselduo!

Hop-Spider.jpg

[dieselduo]

I also use a hop spider when racking to the boiler .Works great for keeping out solids