Vexed by rye fermentation/distillation issues

[Malcontent]

Alright everyone:

Long time listener, first time caller, been having a couple of issues with my rye process I was hoping the hive could help to diagnose. In short: the fermentation results in a wild foam over once the yeast kicks off, and the stripping run from that fermentation runs at a snail's pace. I'm not sure if these problems are codependent or independent. 

Here's my protocol:

1) 180 gallons water+400 lbs rye flour into cooker

2) Adjust pH to 5.2 with citiric, add 100 ml bioglucanase, heat to 112 F, hold for 30 mins

3) Recheck, adjust pH if needed, add 200 ml Hitempase, heat to 160 F, hold for 60 mins

4) Recheck/adjust, cool to 152 F, add 50 lbs distiller's malt, hold for 45 mins

5) Recheck/adjust, begin cooling, add 100 ml Amylo 300 below 130 F, send to fermenter with 30 gallons more water, target pitch temp is 83 F, chiller panel set to hold at 85.

This results in a volume of about 250 gallons, gravity of about 1070, fermented to dryness over 5 days. I also mash twice per fermenter.

I've pitched both USW-6, BE-134, and have co-pitched the two, the problems arise regardless of yeast used.

Fermcap is also used.

This is when the problems begin. The fermentation foams over the first night. The first time this happened I split the fermentation into two fermenters (250 gallons into a 550 gallon) the second mash day and there was enough foaming for the half-volume fermentation to throw over about 20 gallons of mash. So that's problem number 1, violent foaming at the start of fermentation.

Problem number two arises on the stripping run. The still heats up at a normal pace (fermentation temperature to 170) in the first hour, then between 170 and 180 hits a wall, taking about an additional two hours to reach anything resembling a boil. Once spirit does emerge I would describe the rate of flow as a trickle, and this is with the steam valve fully open (I run a copper steam jacketed batch hybrid, 250 gallons). I don't run into this problem with GNS-based distillations or with bourbon stripping runs for that matter.

Some additional notes: I switched out 100 lbs rye flour with 100 lbs ground read wheat for one half-fermentation, this fermentation did not foam over although I have yet to distill it. I've also worked with coarse ground rye rather than flour following the protocol above and did not have the above issues. The strangest phenomenon through all this occurred after one distillation that I gave up on. After watching the still trickle for a few hours I turned the steam off, went home, came back the next day, fired the still up again with the same mash in the still, and was able to produce spirit at a normal pace (i.e. recovered the expected proof gallonage for the mash volume in about 6 hours).

So: What's happening? What have I done wrong? How can I avoid doing this again? Is the demon rye flour in itself to blame as is my hunch?

 

[glisade]

Our rye fermentations foam alot, Fermcap helps but still some foam over but nothing to worry about other than a little loss of product due to foam. Though we also pitch at about 70F and hold fermentation to usually under 80F.  Fully attenuates in about 5 days.  Other than foaming everything runs fine during distillation for us. Does your wash boil at the right temperature based on calculated or measure wash ABV?

[Malcontent]

47 minutes ago, glisade said:

Our rye fermentations foam alot, Fermcap helps but still some foam over but nothing to worry about other than a little loss of product due to foam. Though we also pitch at about 70F and hold fermentation to usually under 80F.  Fully attenuates in about 5 days.  Other than foaming everything runs fine during distillation for us. Does your wash boil at the right temperature based on calculated or measure wash ABV?

To answer your question: yes, I'm at 196-197 F when the vapor temp spikes.

[klattig]

We have precisely the same problem with crazy foam-up & overflowing fermenters.  Our mash profile is quite different (and we don't have your issue in stripping), but the mash volume expands from about 470 gal to overflow the 550gal fermenter.  We lose something like 30 gallons all over the floor each batch - not a fun clean up!

We start at a quite high 19-20 brix sugar content - although we never ferment to 1.000 - we always finish around 1.008.  So I suspect that 2-3brix of the initial reading is beta-glucans, or some other un-fermentable.

I've recently tried adding a beta-glucanase enzyme to the mash process, but it had no effect.  

I'm anxious to hear how others might have tackled this problem!

[JustAndy]

We make 100% rye whiskey from rye flour, and I think your cook needs to go up to a higher temp, and add then bglucanase on the way down after the starch has been hydrolyzed.   

[Malcontent]

1 hour ago, JustAndy said:

We make 100% rye whiskey from rye flour, and I think your cook needs to go up to a higher temp, and add then bglucanase on the way down after the starch has been hydrolyzed.   

JustAndy: From the couple of sources I have the highest gelatinization temperature I've seen for rye is 70 C/158 F. What's the benefit of going higher than that and how much higher would you suggest?

[JustAndy]

Take some of your rye flour and cook it without enzyme and see where the gel temp is, I think there is quite a bit more of a range of gelatinization temperatures than a firm 158F, as the protein, moisture level, etc are all variable lot to lot. We go up to 175, and our bglucanese begins to denature at 60C so it needs another dose after gel/hydrolsis and cooling to work effectively. I'm not a starch scientist, and there might be a more effective way to do it but we rarely see significant foaming in the fermenter and only get serious foaming in the still when there have been mashing/temperature issues.   

[Tom Lenerz]

We've done 75 rye/25 malt, and currently do a 66 Rye/22 Corn/12 Malt. For both we do raw grains with hitempase and bring to around 185 for 20 minutes, cool to 148, add malt and biogluc and amylo 300, rest for 30 minutes then knockout to fermentation temp. We've never had foam issues on rye and have never used fermcap or antifoam. 

[Silk City Distillers]

We've been following a routine very similar to @JustAndy, we gel much higher than 158, which IMHO, is far too cool for unmalted rye.  I'll echo the double BG additions as well, we've been doing a 30 minute glucan rest at the start, and then we add again during the cool down.  Prior to this, we risked erupting out of the top of our fermenters, since we started this, we haven't had any issues.

During our first rye mashes, where we didn't use BG, and were a little bit light on the High Temp Amylase - we ran into issues during cool down.  Our jacketed mash tun simply refused to cool rye mash.  The agitator was not effective, and you needed to scrape away the sides of the tun with a paddle.  From what I could tell, the sticky rye was gelling/solidifying near the edges and acting as an insulator.  Taking it up to the 180-190f level makes the mash process much quicker.

Sounds similar to what you might have been experiencing in the still, rye mash acting as an insulator to prevent heating.

[Blackheart]

+1 for an increase in temp and as Silk suggested, a double shot of BG enzymes works for us.  Watch those pH and temp levels when you add it (use a proper thermometer and pH indicator, not your cooker's dial thermometer).  

If you are still getting foam in the cook, a healthy dose of fermcap does the trick. We have added it at the end of the mash cook, an hour or two after we pitch yeast, or sometimes when we transfer to the still, post ferment.  Results varied, but not by much.

[Georgeous]

I have not made a rye whiskey yet but it is in the pipeline. i have though made many rye beers both commercially and homebrew. When making beers we mash all grains at 147° to 152°F max for maximum starch conversion to sugar. Any higher you release non fermentable sugars. So when geletanizing how do you keep from releasing non fermentable sugars at these high temps? 

 

[JustAndy]

2 hours ago, Georgeous said:

I have not made a rye whiskey yet but it is in the pipeline. i have though made many rye beers both commercially and homebrew. When making beers we mash all grains at 147° to 152°F max for maximum starch conversion to sugar. Any higher you release non fermentable sugars. So when geletanizing how do you keep from releasing non fermentable sugars at these high temps? 

 

How much rye did you use and was it malted or unmalted? If you used unmalted rye, it's likely you got very little fermentable sugar from the grain unless it was very finely milled. The temperatures you quoted are related to the enzymatic conversion of starch to sugar, but first the starch made available for conversion, basically to  be broken apart from the very sturdy way the grain has stored it. With malt, the malting process has already begin this transformation but with raw grain some combination of physical disruption (milling), heat, hydration, acid, and enyzmes is necessary.  

[Silk City Distillers]

20 hours ago, Georgeous said:

So when geletanizing how do you keep from releasing non fermentable sugars at these high temps? 

We're mostly talking about cereal mashes of unmalted grains here - rye, corn, etc.  There is no enzyme to denature, causing non-fermentable sugars.  Malt and Enzymes are added after the cereal mash has been cooled to temperatures (and pH adjusted) to convert all the gelatinized starch to fermentable sugars.  Using something like Glucoamylase, the potential for non-fermentable sugar is just about nil.

When we're talking about cereal mashes, realize that unmalted grain generally requires higher gelatinization temperatures than unmalted grain - and be careful referring to brewing literature that doesn't specify, often times they are mainly referring to malted grain, or even pre-gelatinized adjunct.  Also realize, the higher the temperature, the faster the gelatinization process.  There are large commercial distilleries that use pressure cookers, or inline jet cookers, to heat the mash far above 212F (boiling point) - which results in near instantaneous gelatinization of starch.

[Malcontent]

@Silk City Distillers, @Tom Lenerz, @JustAndy: thanks for your responses, I'll take the mash up to a higher temperature the next time I'm on a rye cycle.

[Falling Rock]

I have the dreaded foam over. As for it not being a problem, I'd say you have a janitor on staff.

In 170 gallon ferment I loose 20 gallons. I've had 3" of foam on 200sg ft. It's a problem for me. Ran out the damn overhead door.

I have come to believe that it is the rye's nutrient value that causes the explosive foam.

Now what if you mashed the rye separately at higher temps?

What if you added it as doses through the fermentation?

I want to increase the % of rye but fear the foam.

[Huffy2k]

Rye is made from distillers tears!

[JustAndy]

I would say if you are having troubles, you should change your process; at the small distillery where I work we make about 75-100 100% rye mashes a year without any more difficulty and than bourbon, oats, wheat, etc. 

[Blakeson]

We have the same issues with our rye. Here are a couple of suggestions that seem to help me out. 

- Lower your pitching temperature. The cooler (close to 70F) when I pitch the Rye fermentation is less aggressive = less foaming. 

- Switch to Patco 376 anti-Foamer. FermCap is super expensive. Patco376 you can throw a liter of that stuff on your fermenter and it does  a pretty great job at anti foam. 

- Before distilling add a little (25-50% of regular dose) of your 1st and 2nd Enzymes into the wash. Ive found this to limit the gummieness of Rye washes which helps heat transfer/distillation. 

Good Luck. I feel like Rye is always the battle whiskey.

[kleclerc77]

I've followed this thread and had planned on cooking our rye upwards of 180° and adding exogenous enzymes and/or malt on the cool down. However, I was reading an old handbook from Seagram's last night (attached) that had a very different mashing protocol for rye. I realize that they have the small percentage of malt(barley) in the mash from the get-go, but wouldn't the same principles apply if you were using exogenous enzymes? If not, it seems like using this method with malt would save a ton of energy in cooking rye, if nothing else. I am assuming here that the enzymatic activity they bring up is due to the barley malt as opposed to the possibility that the rye is malted. Thoughts?

PS: sorry there is a bracket around the bit about wheat mashing, I was taking notes for myself. The same questions come up there too, though.

[jazznblues]

kleclerc77,

I suppose that the described process is somewhat special. I think that if the author doesn't heat the mash to high temperatures, he has to make a fine rye flour, not grist. In this case, I suppose, lower temperatures may be used. But I see some risks in this scheme - some loss in yield and increased content of spoilage bacteria.

There are a lot of mashing/fermentation techniques that home distillers use. Some of them are very far from classical mashing. I mean cold conversion - mixing fluor with enzymes and yeast in cold water. Starch conversion & fermentation goes simultaneously and takes up to 20 days. In this case it is necessary to use antibiotics to prevent mash(=wort) infection. It is strange, but it really works. This practice is widely used by Russian home distillers, who don't want or can't buy expensive equipment or don't like to spend time for mashing process. So, this method is surely the laziest available. There is a version that makes possible to speed up process - so called, "cold conversion with hot start", when fluor/water/enzymes mixture is heated to around 65 C at the process start. This process takes about 1 week to end. And one more version that means using kodzi instead of enzymes/yeast. Kodzi contains special mold, that produces enzymes, and yeast.

[adamOVD]

Sounds to me like he is prioritizing having a low viscosity over gelitizing as much of the grain as possible. Taking a loss in yield to keep the mash more liquid. However, If you are using enzymes you can use glucanase to lower the viscosity of high glucan grains like wheat and rye, but still cook them at a higher temperature. I'm  a bit new to the enzyme game, and haven't worked with rye, but it works well with wheat.

[Silk City Distillers]

Keep in mind that was published in the early 1940s, meaning this way based on activity taking place in the late 30s, early 40s.

I am pretty sure that exogenous high temperature amylase was not "invented" yet, likely not beta-glucanase either.

They didn't have access to the technology that we have today, so their workflows were constrained compared to what we have access to today.

[adamOVD]

5 hours ago, Silk City Distillers said:

published in the early 1940s

Wasn't aware of that. Mixing and moving a gummy mash must have been a lot more complicated as well, adding to the importance of keeping things liquid.

[Hammer Spring Distillers]

I'm interested in the replies here.  We've been open for a year successfully making clear spirits to pay the rent up to now, and finally we're starting our brown spirits.  I'm a Rye fan, so that was a logical start for me.  This week was our first stab at it.  Our mash is essentially 2.5 lb fine rye flour per gallon of water.  We start with bioglucanase and fermcap (glad to learn of a cheaper alternative!), add hightempase at around 140f, raise to 170f and hold for 1/2 hour, cool to 140 then add amylo 300, rest for another 1/2 hour, confirm conversion with a few drops of iodine in a small sample, then cool to 85f.  This is where we adjust the pH, and I see some are adjusting at other points along the way? Then we transfer to the fermenter and pitch yeast (Safspirit M-1).  Our starting gravity was 1.085 which was a little lower than I expected, but workable.  However, the distilling run was A) slow as can be - as stated above, seriously barely a trickle for like 6 hours - it felt like our vodka spirit run!!, then B) only gave about 1/2 of the proof gallons we expected.  The good news is, what we did get tasted GREAT!! just not nearly as much of it as expected.   Here's a part that might explain my low proof gallons - and that's about the method of checking the OG, and FG.  It's way too viscous before conversion to get a good OG reading with a hydrometer (it basically just sits on top of it), so we use a refractometer.  But at the end, as it ferments and thins out, a hydrometer reading is possible... and zeros out to 1.00 after ~4 days, but the refractometer still reads 1.035?  Which one is correct?  Did we still have 4.4% potential (unfermented sugars)? Or was something else, "a-rye"?

JP

[stevea]

3 hours ago, Hammer Spring said:

I'm interested in the replies here. ...

 JP

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.