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Vexed by rye fermentation/distillation issues

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10 hours ago, Hammer Spring said:

Did we still have 4.4% potential (unfermented sugars)? Or was something else, "a-rye"?

1) Keep on truckin'. Once you get it down, it's easy.  We love mashing rye now, it's the shortest and easiest mash day.

2) Make your pH adjustments before each enzyme addition.  5.8 for BG, 5.8-5.6 for HTAA, 5.4-5.2 for GA (roughly).  This is to optimize effectiveness and ensure maximum activity through mashing and continuing through fermentation.  Look at the pH tables for your enzymes, if available, and make a determination of what's optimal, and what works (you don't want to be increasing the mash pH, only stepping it down slowly with each addition).  For example, if you are already at 5.6 after grain additions, don't bother attempting to raise, that becomes your starting pH, only adjust down for GA, and then afterwards.  Bring it down to at least 5.2 before fermentation.  If you suspect you are dealing with bacterial gremlins, push it down even further.

3) Increase your hold time at gel temperature, push it to an hour.  Rye always seems to like it hotter, and longer, than what any chart or table says.  There is a really popular gelatinization temp chart that's made it's way around the internet.  Ignore it, it's garbage.

4) Add your HTAA right after your glucanase rest is complete, it helps keep mash thin.

5) Rye Lies - don't bother attempting an accurate starting gravity.  Even the iodine test can be frustratingly inaccurate.  Especially if you are milling to near-flour.

6) You can try pulling back to 2lb/gal until you have a dialed in process, then attempt to push from there if necessary.  I don't even attempt to push that high, it's not worth it.  We use 1000lb of unmalted rye in 2000l (530g) total mash volume or 450 gallons total water.  We tried pushing to 1100, and it's just not worth the effort.  Also, 1000lb is half of a 2000lb super sack, which makes grain handling easier.

7) The slow distillation - are you using an electrically heated Bain Marie?  Agitator?

😎 Yield - how much of the 3 enzymes are you using?  What's the total mash bill weight?

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16 hours ago, Hammer Spring said:

but the refractometer still reads 1.035?  Which one is correct?

Any alchohol in the solution will throw off the refractometer reading. They are only good for checking OG. So it sounds like the ferment did finish, and I dont know why your yield was so low. Hopefully silk's advise above can get you dialed in.

Edited by adamOVD

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13 hours ago, stevea said:

100% rye is a sort of torture-test.  You might try a <70% and see how it goes.

There are Dupont viscosity reducing enzymes from Gusmer's available aimed at rye & wheat.  I don't have experience but Headstill wrote about them a while back. These reduce the arabinoxylose & hemicellulose 'gums'.  The prices aren't bad at all, but the minimum qty is like 25kg.

IoR is an indirect measure of sugars (and anything else that differs in rotation from water) , OTOH hydrometry is also indirect and just measures the density.  If you want to get hard-core there is a Fehling's test (strips are available as Clinitest) for reducing sugars.  You can even measure glucose (not maltose etc) using a diabetic test meter & strips - very easy & cheap.  In the US these measure in milligram/deciliter with an accurate range ~50-200 mg/dl - so you'll need to understand dilution.  A 100 reading on a diabetic meter is 100mg/dl or almost exactly  0.1 Plato (of glucose only).   I'm not suggesting these as a regular procedure, but it's nice to have a couple tools in the drawer when things are unclear.

Ha, the glucometer is brilliant!  I'm a retired paramedic, so I would love to break out my kit again!  Thanks for the other tips on sugar detection - I know I could also pop $3,500 on a Snap 51, but I left my money in my other pants... 

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20 minutes ago, adamOVD said:

Any alchohol in the solution will throw off the refractometer reading. They are only good for checking OG. So it sounds like the ferment did finish, and I dont know why your yield was so low. Hopefully silk's advise above can get you dialed in.

I knew there was some level of inaccuracy with rotodexterity in the refractometer once alcohol was introduced - just wasn't sure what to expect with this new batch.  Thanks for the reply!

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6 hours ago, Silk City Distillers said:

1) Keep on truckin'. Once you get it down, it's easy.  We love mashing rye now, it's the shortest and easiest mash day.

2) Make your pH adjustments before each enzyme addition.  5.8 for BG, 5.8-5.6 for HTAA, 5.4-5.2 for GA (roughly).  This is to optimize effectiveness and ensure maximum activity through mashing and continuing through fermentation.  Look at the pH tables for your enzymes, if available, and make a determination of what's optimal, and what works (you don't want to be increasing the mash pH, only stepping it down slowly with each addition).  For example, if you are already at 5.6 after grain additions, don't bother attempting to raise, that becomes your starting pH, only adjust down for GA, and then afterwards.  Bring it down to at least 5.2 before fermentation.  If you suspect you are dealing with bacterial gremlins, push it down even further.

3) Increase your hold time at gel temperature, push it to an hour.  Rye always seems to like it hotter, and longer, than what any chart or table says.  There is a really popular gelatinization temp chart that's made it's way around the internet.  Ignore it, it's garbage.

4) Add your HTAA right after your glucanase rest is complete, it helps keep mash thin.

5) Rye Lies - don't bother attempting an accurate starting gravity.  Even the iodine test can be frustratingly inaccurate.  Especially if you are milling to near-flour.

6) You can try pulling back to 2lb/gal until you have a dialed in process, then attempt to push from there if necessary.  I don't even attempt to push that high, it's not worth it.  We use 1000lb of unmalted rye in 2000l (530g) total mash volume or 450 gallons total water.  We tried pushing to 1100, and it's just not worth the effort.  Also, 1000lb is half of a 2000lb super sack, which makes grain handling easier.

7) The slow distillation - are you using an electrically heated Bain Marie?  Agitator?

😎 Yield - how much of the 3 enzymes are you using?  What's the total mash bill weight?

Thanks for the reply Silk City!  I'll be sure to adjust pH earlier in subsequent batches, and increase the rest times as suggested.  We do use an electric bain marie (oil jacket) with an agitator.  I know the heat up time is what it is, but once it's to temperature (192f at this elevation) it still runs dreadfully slow.  I know the lower the abv in the wash/mash, the slower the run will go - so that was kind of the genesis of my hunch that I had unfermented sugars still in there.  We work in 100 gallon sets, so it's 250 lbs grain in just shy of  100 gallons of water, 100 mL biogluc (I know that's more than needed), 300 mL Hightempase, and 30 mL Amylo 300, about a cup of citric to get to 5.8, and 145 g dry yeast.

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On 6/6/2019 at 5:56 AM, Silk City Distillers said:

2) Make your pH adjustments before each enzyme addition.  5.8 for BG, 5.8-5.6 for HTAA, 5.4-5.2 for GA (roughly).  This is to optimize effectiveness and ensure maximum activity through mashing and continuing through fermentation.  Look at the pH tables for your enzymes, if available, and make a determination of what's optimal, and what works (you don't want to be increasing the mash pH, only stepping it down slowly with each addition).  For example, if you are already at 5.6 after grain additions, don't bother attempting to raise, that becomes your starting pH, only adjust down for GA, and then afterwards.  Bring it down to at least 5.2 before fermentation.  If you suspect you are dealing with bacterial gremlins, push it down even further.

3) Increase your hold time at gel temperature, push it to an hour.  Rye always seems to like it hotter, and longer, than what any chart or table says.  There is a really popular gelatinization temp chart that's made it's way around the internet.  Ignore it, it's garbage.

 4) Add your HTAA right after your glucanase rest is complete, it helps keep mash thin.

5) Rye Lies - don't bother attempting an accurate starting gravity.  Even the iodine test can be frustratingly inaccurate.  Especially if you are milling to near-flour.

 

Hi Silk, thanks.  I always find you comments intelligent and on point. 

On 2) I assume most know, but  pH drops with increasing temps, and it's not a trivial amount.   An ATC meter reads pH at the sample temp, which is usually unlikely to be the mash tun temp unless you have a high temp process meter, so you have to apply a correction.  So pH 5.7 for the HTAA at 85C, will read about 6.2-6.3 if the sample is cooled to 25C, and the meter can't account for it.

pH 5.8 @ 50C = pH 6.17 @ 25C 

pH 5.7 @ 85C = pH 6.45 @ 25C

pH 5.3 @ 63C = pH 5.83 @ 25C

The delta-pH values for the three rests would be -0.28, -0.62 if measuring  at 25C.

>>only adjust down for GA, ...

Right!  My view is that you can likely the 'split the difference' in pH for the gum-rest & liquification rest (BG & HTAA).   The HTAA rest does not need to be as complete as the GA rest.  The main purpose of he HTAA rest is to prevent the branched amylopectins from trapping all the water, thus stalling the the hydrolytic enzymes (and of course viscosity).  Acidifying accurately for GA  is critical for good attenuation.

https://www.westlab.com/blog/2017/11/15/how-does-temperature-affect-ph

 

   Variation-of-pH-vs-temperature.png

>> There is a really popular gelatinization temp chart that's made it's way around the internet.  Ignore it, it's garbage.

++.   This (below) is the inaccurate chart.  It dates to a 2009 aussiehomebrewer forum, and the guy says he pulled it together from another amateur HB  forum.  The PDF page attached is from "Food Chemistry" 4th Edition by Belitz, W. Grosch, P. Schieberle.   Note that Rye is way off in the chart.

Gelatinization_temperatures.gif

 

>> 4) Add your HTAA right after your glucanase rest is complete, it helps keep mash thin.

Depending on the specific enzymes used, you may be able to add the HTAA with the GA.  In any case I think the arabinoxylanases + BG may improve the rest time and the SG readings late.   

gelatinization.pdf

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We had issues early on with foaming in the fermenters and with slow stripping runs for Rye.  We started by adding Beta-Glucanase to the mash in two steps, once during heat up when the Rye is gelatinizing at about 135f for an hour (milled to course flour and Alpha Amalyase added) and again after it has been cooled to 80f and is about to be pumped to fermenters (same time we add Gluco Amalyases).  We do a higher cook temperature rest at 170f for 30 min for the corn we add (25%) and then take it up to 190f for half an hour to make sure any other nasties are held at bay, then malt is added during the cooling time at about 160f and another rest.  Without the BG it was a lot thicker and we had more foaming and mashes that didn't finish where we wanted them.  With the BG the foaming went down, we ferment much drier, and heat-up in the still was greatly improved.

In the still, we do find that on occasion we have a rye run that will move very slowly.  Typically this is because there is some scorching at the bottom of the pot (doesn't take much).  To counter this we heat up the rye a bit slower than we do with Bourbon or Corn whiskey.  Doesn't work every time, but we went from issues with every other rye run to 1 in 8.

Super low tech way to help with foaming in the fermenter, spray PAM around the insides a few inches below the top.  It helps break the foam while it rising and has saved me lots of time cleaning up in the morning.

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There is a protein in rye that creates the foam and stops transfer of heat. Sebpro pl will solve these problems for you. Also try viscoferm for viscosity. Haven’t had a foamy rye fermentation in years.

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3 hours ago, Donbroadbranch said:

There is a protein in rye that creates the foam and stops transfer of heat. Sebpro pl will solve these problems for you. Also try viscoferm for viscosity. Haven’t had a foamy rye fermentation in years.

+1 for SEBpro PL. 

I also have been dosing my defoamer slightly diluted onto the top of the mash with a pump sprayer if it's foaming during the cook. It's also easier to knock down foaming in the fermenter with a sprayer. 

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Just started a higher rye mash whisky and learning quickly how much “fun” they are. I can’t help much other than adding in that whatever we are doing doesn’t really create any foaming in fermentation or distillation. Although we have many of the above issues. Not using any de foamers at all. We are not even using enzymes. We are using 60% malted rye and 40% malted distillers malt. One issue is our grain is not even close to flour. Company we buy from claims they mill it as much as they can but it’s half way between what breweries use and flour. Huge grain caps when fermenting. 
 

We start with a high gravity of 1.090 (22 brix) and ferment around 88F using safspirit usw-6 for yeast. We can’t seem to ever get the gravity to fall below 1.040. We did once but this is ferment 9 and no luck. Mash tastes like booze, smells like booze and we get a decent yield out of the still. 60% using the scotch pot top from the start. Starting PH 5.6. Now one thing I hope is okay is that these ferments sit around 3.75 PH almost the entire ferment. We boast to 4.25 a few times during the 5 day ferment with cal carb but it always drops to around 3.75ish

any ideas? Thx

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18 minutes ago, prcdc said:

Just started a higher rye mash whisky and learning quickly how much “fun” they are. I can’t help much other than adding in that whatever we are doing doesn’t really create any foaming in fermentation or distillation. Although we have many of the above issues. Not using any de foamers at all. We are not even using enzymes. We are using 60% malted rye and 40% malted distillers malt. One issue is our grain is not even close to flour. Company we buy from claims they mill it as much as they can but it’s half way between what breweries use and flour. Huge grain caps when fermenting. 
 

We start with a high gravity of 1.090 (22 brix) and ferment around 88F using safspirit usw-6 for yeast. We can’t seem to ever get the gravity to fall below 1.040. We did once but this is ferment 9 and no luck. Mash tastes like booze, smells like booze and we get a decent yield out of the still. 60% using the scotch pot top from the start.

any ideas? Thx

I would try adding some Gluco-Amylase before you pump into the fermenters if you can.  With that much malt you should have no trouble getting the starches converted to sugars, but perhaps you are not breaking them down enough for the yeast.  That and adding something with Beta-Glucanase will help thin things out a bit and allow the yeast more access to the sugars.  We start at a similar SG and I expect to get 1.004 or below in three days.

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@prcdc if you're feeling experimental, you could go for a mash with a lower starting gravity, say somewhere in the 15-17 brix range. That's what we do with our rye ferment, similar grinding of grain, and it always zeroes out. I've heard some people talk about not zeroing out when creating a mash with a very high starting gravity. I've also found that with the forming of grain caps, our yeast definitely needs a little encouragement (hydrating, then mixing with a paddle) to get going and then breaks up that grain cap solely from the agitation caused by fermentation. Found that out the hard way with some monstrous grain caps and inadvertent sour mashes. I also agree with @MikeR on the gluco-amylase front. That stuff is incredible.

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All the info is greatly appreciated! 
 

I have started stirring the grain cap often as I think it does excite the mash. More/different enzymes and try for more milled grain. Also lower starting gravity. At the end of the day I love the flavours coming from the product but it’s too much effort for low % washes. Try try again! 
 

Also we have not had enough runs to get backset yet so the plan is to start using 10% of that to help with the PH drops. Is a 3.75 terrible for the majority of the ferment?

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@prcdc nah yeah ours goes from ~6 to under 4 pretty quickly as well. Haven't had any problems in that department. It seems once the ferment starts rolling, the yeast isn't stressed by the fairly low pH. I'm sure there are people that will say otherwise, or that you may want to keep your pH higher for other reasons. We're getting great results start to finish with no pH adjustment, and reading up on other's issues, consider ourselves very lucky for that!

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I got 99 problems but foaming is not one hehe. The mess...i could only imagine. Thanks again for the info! 

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