Rye Oh Rye!

[RPG]

Take one:  my very first attempt at making rye-dominant whiskey was less than ideal.  The mash bill was 60% rye, 15% soft winter wheat and 15% 2-row barley malt.  Gelatinized rye for 30 mins at 70°C; then wheat and malt at ~65°C for another 30 mins.  OG came out to 1.070.  Was super thrilled!  I filtered the sweet wort; cooled it to ~37°C and pitched Lalvin D47 (wine yeast) which has worked well for me in the past with other grain whiskies.  From the bubbles and other optics, it appeared that fermentation was progressing well.  After 7 days I noticed that the wash was still quite 'dense / thick' unlike the light, lager-color wash I normally get from other grains!  FG was a disappointing 1.035!  Poor attenuation.  Spoke to a distiller buddy who mentioned that for rye whiskies he uses exogenous enzymes (alpha and gluco - amylase). 

Question: Is it true that rye is hard to saccharify with barley in low adjunct proportion (esp. 2-row barley which has relatively low diastatic power vs. 6-row)?  Does a high(er) proportion of malt work?  If so, what should it be?  What else might I have done wrong?  My preference would be to not have to use exogenous enzymes. 

Would appreciate thought and comments.  I love the taste of rye but clearly haven't figured out how to make it!

Thanks in advance

[Kindred Spirits]

What you have experienced is something that happens pretty often with rye. I am assuming you were using an unmalted or raw rye?

When developing the recipe did you do some calculations on the total diastatic power of the mash?  If not you might want to do some and also possibly consider some high DP malt to help the conversion.

 

Is there a specific reason you do not wish to use additional enzymes? They are often used to ensure good conversion, but they are unnecessary if extra care is taken to ensure enough natural enzymes in the grains used.

[RPG]

Thank you Kindred Spirit!  Yes I rye was unmalted.  Interesting to learn that there is a calculation for total DP of the mash.  I will certainly look into it and abide by it in the future.  Also agree that I would have been better served with larger proportion of 6-row barley malt which has significantly higher DP than the 2-row.  Again, many thanks

[Foreshot]

It's easy: http://highwoodsbrewing.com/diastatic-power.php

 

[RPG]

59 minutes ago, Foreshot said:

It's easy: http://highwoodsbrewing.com/diastatic-power.php

 

Many thanks!  very helpful!

[kleclerc77]

Do you check the temperature throughout the fermentation? Our rye/wheat ferments cook themselves up much faster and hotter than our bourbon ferments. It's to the point where we prefer to make bourbon in the summer and rye in the winter to help take that edge off. If your wort is nice and sweet then maybe the incomplete fermentation is because the ferment is cooking itself up too high, too fast.

[Silk City Distillers]

75% of the grain is pretty high in beta glucan, as a result, the mash will be pretty thick and slimy, this is going to impact your gravity measurements, both starting and final, if you aren't doing something about those glucans (using beta-glucanase enzyme or a beta glucan rest as part of a step mash).

Quote

 

Gelatinized rye for 30 mins at 70°C; then wheat and malt at ~65°C for another 30 mins.  OG came out to 1.070.  Was super thrilled!

 

Personally, I think the temp is too low, and that rest too short for raw rye.  This makes me feel like you pulled out a lot of starch and glucan, and didn't necessarily convert it.

What was your distillation yield like?  If it was decent, that points to the glucan issue impacting your fine gravity read, and not necessarily the conversion issue, if it was poor, it was likely both.

Welcome to rye!  On the bright side, once you master rye, there isn't anything you can't do.

[RPG]

11 hours ago, kleclerc77 said:

Do you check the temperature throughout the fermentation? Our rye/wheat ferments cook themselves up much faster and hotter than our bourbon ferments. It's to the point where we prefer to make bourbon in the summer and rye in the winter to help take that edge off. If your wort is nice and sweet then maybe the incomplete fermentation is because the ferment is cooking itself up too high, too fast.

on the lower side, I'd say in the lower side ~ 20°C or 69°C.  I'll make a note of seasonality associated with rye and bourbon.  Thank you

 

11 hours ago, kleclerc77 said:

Do you check the temperature throughout the fermentation? Our rye/wheat ferments cook themselves up much faster and hotter than our bourbon ferments. It's to the point where we prefer to make bourbon in the summer and rye in the winter to help take that edge off. If your wort is nice and sweet then maybe the incomplete fermentation is because the ferment is cooking itself up too high, too fast.

 

[RPG]

4 hours ago, Silk City Distillers said:

75% of the grain is pretty high in beta glucan, as a result, the mash will be pretty thick and slimy, this is going to impact your gravity measurements, both starting and final, if you aren't doing something about those glucans (using beta-glucanase enzyme or a beta glucan rest as part of a step mash).

Personally, I think the temp is too low, and that rest too short for raw rye.  This makes me feel like you pulled out a lot of starch and glucan, and didn't necessarily convert it.

What was your distillation yield like?  If it was decent, that points to the glucan issue impacting your fine gravity read, and not necessarily the conversion issue, if it was poor, it was likely both.

Welcome to rye!  On the bright side, once you master rye, there isn't anything you can't do.

You're right on many fronts I feel.  I anticipated high β-glucan, and consequent viscosity, so added boiled rice hulls.  You're also correct about the wash being too thick and slimly (dense) which is largely due to unfinished business with starch conversion.  Not entirely convinced gelatinization was an issue because I did get the grist moisture level up (evidenced by a high OG), which unfortunately only told half the story ie., starches + fermentable sugars.  I will bare in mind the longer rest in the future.  Distillate yield was anemic I'd say on a ~2.75 gallon wash, I managed 0.2 gallons in my strip run.

Lots of learning from this forum!  a) DP for individual mash calculations was news to me! b) Feel gluco-amylase might help with β-glucanase deficiency due to small malt adjunct.  I'm told gluco-amylase continues to convert well into fermentation (like limit dextrinase).  Team, many thanks!!

[kleclerc77]

Also - I know some people ferment hot, which you can pull off with specialized whiskey yeasts. Your starting temperature is way hotter than recommended for the yeast you are using at the moment too. It recommendeds the range of 18C-28C. So not only is it cooking itself up way too hot, it's way too hot to begin with. We ferment cooler even with whiskey yeast, but to make this yeast perform optimally you wouldn't want it to get much hotter than 28C. It seems you're conversion isn't the issue if it's sweet and reading ~17brix. If the viscosity is really unworkable, aim for closer to 15 brix or lower, or consider using some exogenous alpha and/or gluco amylase. Our rye mash is definitely more of an oatmeal consistency than our bourbon mashes, it's just the nature of the unmalted rye grain. I think ultimately you are frying your yeast, but otherwise are doing a good job mashing.

Edit: in your initial post you mention pitching yeast at 37C, but in a response mention it's more like 20C so I may be off. My take above was based on your pitching when your mash is at 37C.

Edited March 31, 2022 by kleclerc77

[Silk City Distillers]

Quote

I'm told gluco-amylase continues to convert well into fermentation

This is correct, GA will continue to gnaw on your starches throughout the fermentation process, not only dextrin, but this includes ungelatinized starches to some extent as well.  There are some interesting old studies that show that glucoamylase can actually bore into starchy endosperm of grain.  So consider it an insurance policy against an incomplete gelatinization/saccharification process.

 

[RPG]

4 hours ago, kleclerc77 said:

Also - I know some people ferment hot, which you can pull off with specialized whiskey yeasts. Your starting temperature is way hotter than recommended for the yeast you are using at the moment too. It recommendeds the range of 18C-28C. So not only is it cooking itself up way too hot, it's way too hot to begin with. We ferment cooler even with whiskey yeast, but to make this yeast perform optimally you wouldn't want it to get much hotter than 28C. It seems you're conversion isn't the issue if it's sweet and reading ~17brix. If the viscosity is really unworkable, aim for closer to 15 brix or lower, or consider using some exogenous alpha and/or gluco amylase. Our rye mash is definitely more of an oatmeal consistency than our bourbon mashes, it's just the nature of the unmalted rye grain. I think ultimately you are frying your yeast, but otherwise are doing a good job mashing.

Edit: in your initial post you mention pitching yeast at 37C, but in a response mention it's more like 20C so I may be off. My take above was based on your pitching when your mash is at 37C.

37C is what I have been using.  20 C was the ambient fermentation temperature.  Point on high pitch temp noted!  Thank you  

[RPG]

4 hours ago, Silk City Distillers said:

This is correct, GA will continue to gnaw on your starches throughout the fermentation process, not only dextrin, but this includes ungelatinized starches to some extent as well.  There are some interesting old studies that show that glucoamylase can actually bore into starchy endosperm of grain.  So consider it an insurance policy against an incomplete gelatinization/saccharification process.

 

Understood!  Many thanks my friend

[RPG]

Take two:  Followed most of the directions from this string except pitching temp as I had mashed before kleclerc77's input (apologies kleclerc77).  a) similar mash bill - 60% rye; 27% corn and 13% 2-row malt (barley); b) Cooked corn at 185°F for 45 minutes; then Rye and malt at at 165°F for 45 minutes; added exogenous alpha amylase at 150°F.  c) unlike previous time, I decided not to filter the wort rather went for grain-in fermentation. d) SG came out to 1.065.  Cooled wort to 98F (sorry kleclerc77) and pitched red star dady yeast.  Also added glucoamylase.  observed good bubbles.  Day 6 of fermentation a) observed much lighter wash with thick slurry at the bottom.  Also noticed froth marks all over the carboy.  b) I did filter the wash ... needed to agitate with a large spoon due to high viscosity.  c) FG on hydrometer came out to 1.000 indicating 100% attenuation; 7.88% abv wash.  However refractometer told a different story - FG 1.025 indicating 57% attenuation with 4.57% abv.  Point to make - in all my prior readings, hydrometer and refractometer have come in close (delta of .05).  This was a material difference.  Also want to point out that from approx. 2 gallon wort, port filtration, I probably ended up with a little over a gallon of wash (possibly due to grain in).  Sincere appreciation to everyone on this post.  thank you

[Silk City Distillers]

If you are using a refractometer to measure final gravity, you need to use a calculator to take into account the alcohol in the final, otherwise your measurement will be trash.

Using a calculator to adjust for alcohol, I get 8.2% on the refractometer, vs 8.5% on the glass (1.065-1.000=8.5%) - that's ballpark enough.

https://www.brewersfriend.com/refractometer-calculator/

 

[RPG]

10 minutes ago, Silk City Distillers said:

If you are using a refractometer to measure final gravity, you need to use a calculator to take into account the alcohol in the final, otherwise your measurement will be trash.

Using a calculator to adjust for alcohol, I get 8.2% on the refractometer, vs 8.5% on the glass (1.065-1.000=8.5%) - that's ballpark enough.

https://www.brewersfriend.com/refractometer-calculator/

 

Noted!  Many thanks!  

[kleclerc77]

On 4/3/2022 at 2:08 PM, RPG said:

Take two:  Followed most of the directions from this string except pitching temp as I had mashed before kleclerc77's input (apologies kleclerc77). 

 Cooled wort to 98F (sorry kleclerc77) and pitched red star dady yeast.  

Don't apologize to me, apologize to your yeast! 🤣

[SlickFloss]

I'm assuming you're running these in a pot? Whats your grist ratio? Are you brewing with city or softened water? Roller or hammer milled? What kind of screening done to your grain? Whats ash content of grain? Organic or commodity Rye? Do you know the varietal? How does your PH track through your ferment?

[RPG]

Column still with 5 plates (copper plates).  1 : 1.5 grist : liquor ratio (little higher due to high rye and corn content).  Distilled water.  Hammer mill coarse (hence no screening - but high fine-flour fraction).  1.3% ash content in rye (on the label - I didn't analyze).  Commodity; winter grazer 70 rye; commodity yellow dent #2 corn; soft winter wheat.  pH circa 5.4 maintained throughout mashing to fermentation.