Teach me about stalling mashes, please

[BoomTown]

I’ve been at this for several years now, took a hiatus due to an illness, and now have re tooled and am restarting. Have moved to a new hi-rise, different city, and my mashing techniques are failing me.

I’m following recipe guidelines as closely as I can, have reviewed my notes from years ago, but am still stymied by this problem

I’m making 5 gal mashes, all grain with a 55% Corn, 30% wheat, and 15% Malted, 6-row barley. pH out the tap runs at 7.0, drops to 5.3 when the grains are added, and initial Original gravity ranges between 1.065 and 1.073. I cast DADY at 2 tablespoon at 100°F, and the mashes kick off nicely. They bubble away for 4 days, fading out until yeast stops working at 6th days, with temperatures kept at 80.

Problem is, the SG freezes at 1.030. I used to get a finish at 1.003 or .999 regularly. pH at the finish is 3.4.

I’m treating pH to lift it above 5, recasting yeast, but can’t get it to re start. The mash tastes drying, has a faint vinegary smell.

Any ideas for what I might be missing?

Can’t seem to get a complete fermentation cycle…

[MihiT]

Others may have more experience (I'm a born and raised hick) but I'd suspect the townie water...flourine or chlorine or something else.

[NZChris]

For any type of wash that has a history of giving me pH problems, I put some whole, large, shells in at the start, recording their weights, before and after, for future reference.

[BoomTown]

For any type of wash that has a history of giving me pH problems, I put some whole, large, shells in at the start, recording their weights, before and after, for future reference.

What kinds of shells? Sea shells? Egg shells? Oyster shells?

[BoomTown]

Others may have more experience (I'm a born and raised hick) but I'd suspect the townie water...flourine or chlorine or something else.

I kinda thought the heat up part of the cycle would cast off the chlorine, but there could be othe chemicals not known to me. Will try with bottled water…

[shadylane]

I Have moved to a new hi-rise, different city, and my mashing techniques are failing me.

Different water chemistry ?
Malt isn't as good ?
The mash temp, SG or pH measurements are inaccurate for whatever reason ?
By chance, are you using a refractometer to measure the specific gravity instead of a hydrometer ?

[8Ball]

I Have moved to a new hi-rise, different city, and my mashing techniques are failing me.
[/quote
By chance, are you using a refractometer to measure the specific gravity instead of a hydrometer ?

+1
My thoughts also, shadylane.

[Demy]

Should we first exclude some as: sure that your hydromenter is working? By chance do you use a refractometer? The presence of alcohol in the refractometer will give an incorrect measure, in the hydrometer you don't have this problem ... I would say to start from this to understand the problem, because it would seem that fermentation is completed.

[The Baker]

What kinds of shells? Sea shells? Egg shells? Oyster shells?

Yes.

Geoff

[jonnys_spirit]

Are you usung any backset? If somhow much? That’ll probanly have a higher SG in many cases.

[BoomTown]

Are you usung any backset? If somhow much? That’ll probanly have a higher SG in many cases.

No backseat, still working on a simple AG with fresh water.

[BoomTown]

What kinds of shells? Sea shells? Egg shells? Oyster shells?

Yes.

Geoff

So, that means, any old shells? What happens? Do they dissolve?

[BoomTown]

Should we first exclude some as: sure that your hydromenter is working? By chance do you use a refractometer? The presence of alcohol in the refractometer will give an incorrect measure, in the hydrometer you don't have this problem ... I would say to start from this to understand the problem, because it would seem that fermentation is completed.

I have both. I’ve calibrated the refactometer to the hydrometer using distilled water and a simple sugar mix. They read the same…

[BoomTown]

For any type of wash that has a history of giving me pH problems, I put some whole, large, shells in at the start, recording their weights, before and after, for future reference.

OK, have some shells from an escargot horsd’oeuve…, a. Tossing 3 in.

[elbono]

So, that means, any old shells? What happens? Do they dissolve?

They need to have calcium carbonate, all those do. I use crushed oyster shell for chickens from the local feed store because it's cheap. I just throw a couple of handfuls in when I pitch yeast, if you want data put them in a bag and weigh before and after fermentation.

If pH drops they dissolve and keep it from getting to low. if not they just sit there.

Food or laboratory grade calcium carbonate $$$ works to.

[BoomTown]

For any type of wash that has a history of giving me pH problems, I put some whole, large, shells in at the start, recording their weights, before and after, for future reference.

OK, have some shells from an escargot horsd’oeuve…, a. Tossing 3 in.

Oh by Golly! 2 hours after adding snail shells, I got new bubbles!
Hoping they last!

[BoomTown]

For any type of wash that has a history of giving me pH problems, I put some whole, large, shells in at the start, recording their weights, before and after, for future reference.

OK, have some shells from an escargot horsd’oeuve…, a. Tossing 3 in.

Oh by Golly! 2 hours after adding snail shells, I got new bubbles!
Hoping they last!

Well, they pooped out, leaving an SG of 1.042. Am going to run this, and start over with sanitized mashing and fermentation units. Will start with a basic, 5 gal sugar wash, then a simple corn mash with enzyme extracts, then a wheat with enzyme, all the while watching for the stall…

Maybe, what ever is the cause of this will emerge.

[shadylane]

I have both. I’ve calibrated the refactometer to the hydrometer using distilled water and a simple sugar mix. They read the same…

Both are accurate for measuring starting gravity.
By the time fermentation is finished, the refractometer will read higher than the hydrometer.

On a side note.
Sugar washes are prone to stalling from low pH or lack of nutrients.
A proper mash has plenty of nutrients and buffering.
If the yeast quit, it's most likely due it having consumed all the fermentable sugar.

[BoomTown]

On a side note.
Sugar washes are prone to stalling from low pH or lack of nutrients.
A proper mash has plenty of nutrients and buffering.
If the yeast quit, it's most likely due it having consumed all the fermentable sugar.

Is it possible that the sugars being indicated after the yeast quits is of a non-fermentable type? If so, how can they too be converted to something yeast can consume? What in the mashing process produces these ‘dead’ sugars?

[shadylane]

Is it possible that the sugars being indicated after the yeast quits is of a non-fermentable type? If so, how can they too be converted to something yeast can consume? What in the mashing process produces these ‘dead’ sugars?

Dead sugars isn't a good description.
Yeast needs simple sugars that are only 1, 2 and sometimes 3 sugars linked together.
With a mash bill of only 15% malt, the mash process needs to be spot on to convert all the starches into fermentable sugars.

For insurance to keep you from getting thirsty while you're mastering the art of mashing.
I'd recommend buying high temp alpha enzymes to convert starch into dextrins.
And gluco enzymes to chop the dextrins into the simplest sugar Glucose.

The #1 symptom of poor conversion is a high final gravity.
The 2nd reason for a high final gravity is a newly acquired refractometer.

[still_stirrin]

I’m betting you didn’t do an iodine (starch) check when you mashed in your grains did you? That would tell you if the starches were converted (iodine remains amber colored) or not (iodine turns purple-black).



I bet that the contribution to your ferment from the grains was simply starch, which will show a higher specific gravity just like sugars, although the starch won’t ferment out. Plus, your wort will remain cloudy rather than settle clear if the starches were fully converted.

Bottomline here, you need to focus more on your mashing protocol. You need to learn how to convert the starch more effectively. Liquid enzymes will help with that, but you’ll need to pay attention to temperatures and the pH to make the environment right for the enzymes to work best.

Also, proper grind of the grains will make the carbohydrates in the grains more available to the enzymes for reduction. So, pay attention to how you mill your grains. It will improve the extract efficiency.

All grain mashes can be time consuming but rewarding. Beer brewers know and understand this. And when proficient at it, the mash process is a key part of the “craft of the brew”. Master it, and hobby distilling will be much more enjoyable (and rewarding).
ss

[BoomTown]

I’m betting you didn’t do an iodine (starch) check when you mashed in your grains did you? That would tell you if the starches were converted (iodine remains amber colored) or not (iodine turns purple-black).



I bet that the contribution to your ferment from the grains was simply starch, which will show a higher specific gravity just like sugars, although the starch won’t ferment out. Plus, your wort will remain cloudy rather than settle clear if the starches were fully converted.

Bottomline here, you need to focus more on your mashing protocol. You need to learn how to convert the starch more effectively. Liquid enzymes will help with that, but you’ll need to pay attention to temperatures and the pH to make the environment right for the enzymes to work best.

Also, proper grind of the grains will make the carbohydrates in the grains more available to the enzymes for reduction. So, pay attention to how you mill your grains. It will improve the extract efficiency.

All grain mashes can be time consuming but rewarding. Beer brewers know and understand this. And when proficient at it, the mash process is a key part of the “craft of the brew”. Master it, and hobby distilling will be much more enjoyable (and rewarding).
ss

Very helpful. Thankyou.

[BoomTown]

[
I bet that the contribution to your ferment from the grains was simply starch, which will show a higher specific gravity just like sugars, although the starch won’t ferment out. Plus, your wort will remain cloudy rather than settle clear if the starches were fully converted.

ss
[/quote]

Thanks for your earlier note. I repeated mashing yesterday, taking your advice, about revisiting my techniques, even extending the timing of the heating portions. Iodine test confirms starches not converted to sugar. OSG = 1.045, pH 5.5, Temperature 95°F. Top layer is cloudy, not clear.

Is there a next step to convert the retained starches to sugars? What part in mashing process needs adjustment to assure full conversion in future mashes, assuming pH and water Temperature Discipline is maintained?

Is it as simple as increasing the amounts of enzymes applied? Is there a low temperature enzyme that would affect conversion at temperature between 80°- 90°?

[/quote]

[still_stirrin]

… Iodine test confirms starches not converted to sugar.
OG= 1.045,
pH 5.5,
Temperature 95°F.
Top layer is cloudy, not clear.

Is there a next step to convert the retained starches to sugars? <— You’re asking about a wort/mash into which you’ve already pitched the yeast? If so, a dose or 2 of liquid gluco-amylase enzymes into the fermenter might help the active enzymes to continue to reduce starches. But, you’ll need to wait on the enzymes to finish … it could be weeks, or more.

What part in mashing process needs adjustment to assure full conversion in future mashes, assuming pH and water Temperature Discipline is maintained? <— PATIENCE. You need to add more TIME to your mash schedule. When the enzymatic conditions are proper, time is all that is needed to complete conversion. “How much time”, you ask … until the iodine test proves you’re converted.

Is it as simple as increasing the amounts of enzymes applied? <— Increasing the amount of enzymes will increase the conversion rate to a point. But, only if the conditions are correct. Over utilizing enzymes can be a waste of investment if you don’t use them properly.

Is there a low temperature enzyme that would affect conversion at temperature between 80°- 90°? <— The enzymes that work at that temperature are the beta glucan reducing enzymes. In order to improve saccharification of “fermentable” sugars, you need to hold the temperature between 140*F to 150*F. The gluco-amylase enzymes will work best in that range, although they will work at lower temperatures but significantly slower. The gluco-amylase enzymes also like the pH slightly acidic (pH 4.5-5.0).

Based upon your succinct description, I would first suggest double checking and paying attention to the grind. Your corn should be ground to a fine meal, not flour, but very small bits. Definitley grind more than simple “cracked corn”. And for your other cereal grains, if they have husks, you need to crush the grains to open the husks. Wheat berries (huskless) must also be ground to a fine grind like the corn.

Note here - if you're using raw grains, malting them will soften the kernal shell and also initiate enzyme activity to help start the starch reduction. But malting is a completely new topic and is best covered in a new thread. It isn’t difficult to do, just that you’ll need some special equipment and lots of patience.

In conclusion, I suggest going to a hoembrew beer website and join their forum in order to gain more knowledge of how to brew. Beer sites have a great knowledgebase for the brewing population and that skill is definitely beneficial to this hobby. You’ve got a lot of learning in front of you, so settle in and get started. It’s fun to learn.
ss