Converted Mash won't separate

[Twisted Brick]

Even after waiting overnight for my bourbon mash to separate enough to get a SG reading, there is no clear liquid to collect. This has occurred over the last 3 or 4 mashes after dozens of successfully converted batches.

Corn is medium meal, finely milled rye, and standard milled 2-row. HTL and gluco along with backset. The converted mash is sweet like always, and the strip ABV measured at the spout is normal. I really haven't changed anything - I wonder if my 2-row DP is aging, even though I'm using enzymes?

Any ideas what gives?

[MartinCash]

Did you do a starch test? It might help diagnose. Rye is pretty gloopy, did you use more than you'd done before, or do a protein rest?

[ShineonCrazyDiamond]

Get a refractometer for sg. Hydrometer for fg.

[greggn]

HTL and gluco along with backset.

Any ideas what gives?

Was it a high-gen backset ? Could you have lowered the pH into the range where enzyme activity is degraded ?

[Twisted Brick]

Did you do a starch test? It might help diagnose. Rye is pretty gloopy, did you use more than you'd done before, or do a protein rest?

The grainbill has been essentially identical, batch 6/7 to fill a 5gal barrel. I haven't had a problem with b-glucans at this percentage.

18.5lbs cornmeal (72%)
4.5 rye malt (17%)
2.75lbs 2-row (11%)

Was it a high-gen backset ? Could you have lowered the pH into the range where enzyme activity is degraded ?

Yes, the backset was high-gen. Thanks for pointing that out. I'll bet that's the problem. I gave up on the pH strips I bought because they're so imprecise. The next batch I'll use an acid instead of backset. Gonna have to look into a refractometer. They're more accurate, methinks.

Thank you gentlemen.

[shadylane]

Maybe check the calibration on your thermometer?
Or possibly the enzymes are past date?

[Twisted Brick]

Maybe check the calibration on your thermometer?
Or possibly the enzymes are past date?

My enzymes are maybe 6mos new, so I’m good there. There is a very good chance of my thermometer being out of calibration. I checked it against a digital thermo about a year ago and it was off 5 degrees.

I need to commit to getting a lab quality thermometer and for that matter, a lab quality hydrometer / spectrometer.

[ideasinbeer]

A thermopen is relatively cheap, with good enough operating range to suit most needs.

[Twisted Brick]

On this last batch of bourbon I made my standard corn/2-row starter but went bigger (3.5gal) for reserve starters. It separated nicely like always and the 3gal surplus went into the fridge for later batches. It wasn't until the following main mash (4.5lb of rye in 25lb grain bill) didn't separate (again) that it occurred to me (duh!) it must be the rye causing it. This is the highest percentage (18%) of rye I've done to date and used citric acid instead of backset for pH adjustment.

Heads up to those who go high rye or all rye batches. In higher percentages, rye is seriously glutinous (glucan-ous?). Don't expect to get enough separation to measure a starting gravity. If you anyone can offer a trick on how to do it, I'm all ears.

[zapata]

beta glucanase like seb-flo or a beta glucanase plus xylenase (plus other stuff) like ViscoSEB ought to help. (personal rep for seb-flo, viscoseb is on my list to try when the sebflo runs low). Malt has both glucanase and xylenase, but I think you more or less gotta step mash on the way UP, which you probably aren't doing with corn. Unless you have a steam kettle or steam injector? Worst case (actually isn't that bad) is to step mash your rye malt and/maybe malt upwards in a separate pot while you gelatinize (or cool) your corn. I think for endogenous enzymes it's about 95-99 for a protein rest and 113 for the glucan rest? (I'm sure both are in how to brew).

I've heard you can use the exogenous enzymes on the way down if the gel isn't too bad up to that point, but I've also read sometimes that doesn't work so the best bet is stepping up. On the plus side, I've read but can't really vouch for as I never did a control, but supposedly rye tastes better if you never take it up to corn gel temps.

I've been on a kick of avoiding the exogenous glucoamylases when I can. I'll still use the HT alpha for corn because OMG it's a dream, but I let malt handle the GA conversion. Especially when using beer yeasts I think the flavor profile is better with malt than GA. Still ferments dry but I think the yeast is getting more maltoses than simple sugars, and I think some yeasts prefer it. Good news is malt enzymes will survive the ride up just fine and still convert everything. That's what I did with my last rye heavy, which I think was about 25% of each rye, rye malt, corn, barley malt. Ryes and barley stepped up in my brewing rig while corn was cooling off. I wouldn't have tried to sparge it, but it was manageably thin.

It's a bit of a math mash and both start off kinda thick. But HTL thins corn like nobodies business so no biggie there. And you might want to actually calculate when to combine them because the rye mash will be hot enough you don't get the same temp drop as if you were adding cold malt to the corn.

[NZChris]

If you are really unlucky, there is a bacterial infection that can cause a ferment to go 'ropey'. It behaves like snot.

[Twisted Brick]

Thanks, Zapata. I’m kicking myself for not identifying this before I started my mash. I would have loved to test a separate stovetop stepped rye mash with rests at 100F and 113F. I even have an unopened bottle of SEBFlo Glucanase I got a while back.

Yes, I’m a strong believer in preserving individual grains’ flavor potential by only introducing each grain at its own optimal temp. In this case I’m using a home-malted organic rye and this test might have given me the opportunity to measure the DP my malting processes yield.

I agree with HTL’s effectiveness. At 2.25lbs/gal, my med-milled corn gets quite thick at 200F and I usually wait til 180F before adding the recommended 6ml of HTL. Just for grins, on this mash I added 2ml of HTL at dough-in to see if it would thin the corn enough to potentially increase the rate of gelatinization. After 15min or so at 190F I found the corn was already consistently watery with a good-sized layer of clear on top. Pretty effective stuff. For insurance I still added another 4ml, but if I was ever running low, I think I would just forge ahead.

I have built a steam injector just for handling a keg-sized stepped rye mash, but it’ll be a bit before I can test it. I will certainly report how it works out.

[Twisted Brick]

beta glucanase like seb-flo or a beta glucanase plus xylenase (plus other stuff) like ViscoSEB ought to help. (personal rep for seb-flo, viscoseb is on my list to try when the sebflo runs low). Malt has both glucanase and xylenase, but I think you more or less gotta step mash on the way UP, which you probably aren't doing with corn. Unless you have a steam kettle or steam injector? Worst case (actually isn't that bad) is to step mash your rye malt and/maybe malt upwards in a separate pot while you gelatinize (or cool) your corn. I think for endogenous enzymes it's about 95-99 for a protein rest and 113 for the glucan rest? (I'm sure both are in how to brew).

This is a follow up to my original inquiry.

Yesterday I conducted a stepped (UP) stovetop 100% rye mash concurrently with my bourbon mash in a keg. I used 3.5lbs of rye malt and 1lb of caramel rye malt that were home-malted. The rye was milled fine and added to 2.25gal of 110F water (2lbs/gal). The grains settled for a glucan rest at 107F for 45min and sac rest at 145F (90min). I was happy to see that the converted mash separated nicely and the resulting gravity was a temp-corrected 1.055. This number was especially encouraging since ~30% of the rye (caramel malt) had had its enzymes denatured during kilning).

I added the converted rye, gluco enzymes and 3lbs of 2-row to the main corn mash and held it wrapped at 149F for several hours. I cooled it to 98F but left it overnight to see if it would separate enough for a gravity reading in the morning. It had cooled to 80F in the morning and had a beautiful layer of clear liquid on top. The gravity of this 2.25lb/gal mash was 1.071.

I used HTL enzymes on the corn and gluco on the whole mash, but because I didn’t use glucanase enzymes on the rye mash, it tells me my malting regime is creating a good amount of enzymes. I'm hoping the glucan rest contributed to the converted mash separating nicely and not some other factor I am missing. I am still surprised I didn't encounter any of the slimy gumminess others have reported, but I think I’m gonna encounter this when I attempt to steam-cook a larger 100% rye mash on its own.
.

rye malt

.

rye malt milled fine

[zapata]

Sweet! What kind of rye are you malting? As in where are you sourcing it? Local farmers, bulk bin at the food co-op, etc?

[Twisted Brick]

Thanks for nudge, Zapata.

These rye berries came from Central Milling in NorCal. Their website has a boatload of raw grains and flours and is a virtual baker’s (and Distiller’s) candy store. All of their products are top-quality. At $25-30 per 50lb sack, their organic grains are very reasonable and their wheat and rye malt up beautifully. I was on a trip attending my daughter’s graduation but managed to pick up 250lbs of grain. They have changed the way I look at grain quality now.
.

[zapata]

Hell yeah! I can absolutely see paying those prices for quality organic grains.