All Grain with Millet: Epic Fail. Thoughts?

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Michaelinwa

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I did my first, possibly last, all grain effort with terrible results.

Used:

7lbs pale millet, 1.5 lbs rice hulls, 0.5lb biscuit rice, 0.5 lbs crystal millet. Pretty fine grind, but not flour.

2.25 gal strike water at 180F, gave me a 162F mash. Seemed pretty dry; little in the way of spare water in it. Probably mis-measured, just seemed like it needed more. Anyway, I made sure there was some liquid under the surface, but something seemed off there.

Added about a quarter teaspoon of the AMG-300L amylase from Brewcraft. Label says this is for about 122F so suspect it does nothing at normal mash temps.

Failed iodine test at 90 minutes, also at 2 hours. OG of wort PRIOR to much sparging was only 1.02. After boiling down to 3 gallons, specific gravity was only about 1.03. Tossed the batch.

I ran a couple tests on just one pound of millet, to try to get a decent OG. With one pound of millet, strike temp of 158F, direct fired to 165/166F, placed in thermal jug with about 1/8th teaspoon of AMG-300L, after 1hr and 40 minutes, OG of wort with sparge of half quart (at most) OG was 1.04. In a prior test, I skipped the temp rise to 166F, and just had a strike temp at 158F, with AMG-300L. Results were no better. Nothing passed iodine test. All efforts today looked cloudy, or starchy, although there was some sweetness to the wort.

I have a few thoughts: AMG-300L is not effective at these higher temps? I'm not able to hold the temps high enough for 90-120 minutes in an insulated container (temps were in the high 140s after 2 hours for my brewing effort. In the test, temps dropped to low 140s after 1 hour, 40 minutes). Despite Igliashon's success with a 158F mash, I may need to hold the grain at 165 for 15-20 minutes to gelatinize the grain?

Would welcome any thoughts from those of you who have mashed millet successfully.

Also, what type of amylase are you using?

Thanks.
 
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Just a quick update to this. I did yet one more test on 1 pound of millet. This time I held the temperature at 164-166F for about 15-20 minutes, then dropped it into a thermal jug with 1/8th teaspoon of AMG-300L. I let it mash for 2 hours. After 2 hours the temp had dropped to 140F so I ended the mash. It still failed the iodine test, again. This time the specific gravity was 1.048. Definitely an improvement, but far from where I think it needs to be, and clearly there is significant starch left in the mash.

Either I need a more effective amylase--would love to know what people use and where to get it, or I would have to try a longer gel rest.

Only other thought is that more grain would probably hold the temp higher for longer, which might help conversion.
 
I don't know much of anything about using millet in brewing. However, I will perhaps suggest this. Maybe you need to cook the millet prior to using it in a mash? I know this is true when using oats if they are not quick oats (pre-cooked). I've precooked some grits before that I intended to use in a mash with great success.

I would try an experiment with mashing again. This time I would precook the millet (boil the hell out of it for a while) before trying to mash it. Let us know how things turn out.
 
I don't know much of anything about using millet in brewing. However, I will perhaps suggest this. Maybe you need to cook the millet prior to using it in a mash? I know this is true when using oats if they are not quick oats (pre-cooked). I've precooked some grits before that I intended to use in a mash with great success.

I would try an experiment with mashing again. This time I would precook the millet (boil the hell out of it for a while) before trying to mash it. Let us know how things turn out.

Thanks. I think holding the grain initially at around 166F is essentially cooking it, in that it should gelatinize there. Above 168F I understand that the natural enzymes are denatured, so conversion would presumably be harder/impossible. Amylase might address that, but I am not convinced that I have amylase that works at these temps.
 
Thanks. I think holding the grain initially at around 166F is essentially cooking it, in that it should gelatinize there. Above 168F I understand that the natural enzymes are denatured, so conversion would presumably be harder/impossible. Amylase might address that, but I am not convinced that I have amylase that works at these temps.

I assumed you was adding the amylase because the millet did not have any enzymes to make the conversion itself. Unless the millet was malted, I doubt there would be any natural enzymes anyhow. That would explain why your attempts has been less that successful. We all know millet can be used to make a fermented beverage. It has been used for centuries in some cultures. (I actually read up on it after reading your post :) )

If you are relying on adding amylase I would go ahead and boil the crap out of the millet to be absolutely sure the starches are freed.

One other thing to consider, is your amylase addition fresh? I don't know how these thing last over time, but it is something to consider. I bought some once and I swear it has lost it's magic. Maybe it's just me, but it doesn't seem to work as well as it once did.
 
I assumed you was adding the amylase because the millet did not have any enzymes to make the conversion itself. Unless the millet was malted, I doubt there would be any natural enzymes anyhow. That would explain why your attempts has been less that successful. We all know millet can be used to make a fermented beverage. It has been used for centuries in some cultures. (I actually read up on it after reading your post :) )

If you are relying on adding amylase I would go ahead and boil the crap out of the millet to be absolutely sure the starches are freed.

One other thing to consider, is your amylase addition fresh? I don't know how these thing last over time, but it is something to consider. I bought some once and I swear it has lost it's magic. Maybe it's just me, but it doesn't seem to work as well as it once did.

Actually, the millet is malted, so it does have the ability to convert the starch, though not as effectively as barley. Not sure about the amylase freshness. What type of amylase do you use, and where do you get it? Does it work at 150-160F?
 
The stuff I have is a formula from BSG. Website bsghandcraft.com

I always used it at regular mashing temps 140-160F.

I still have quite a lot of it. I bought it because I use to be terrible at controlling mashing temps. I would find that my mash temp was 165F and I would kick myself for destroying all my Alpha Amylase. I would let the mash cool to 150 and then add some of the formula. It worked pretty good as a way to save the brew when I screwed up badly.

Anyhow, I have no idea of the diastatic power of malted millet. It may have low diastatic power to start with. Hopefully someone who has actual experience with this stuff will chime in on this forum soon.
 
I suspect that you are right about denaturing the AMG 300.

I dont rely on the enzymes in the malt at all...I denature them during a 175 F rest for 90 min, thermaly stable A amylase is added during this rest.

Then I drop the temperature to 140 F, and add an amylase that is active at that temperature. This rest lasts for 120 min. If I were using AMG 300 I would rest at 120 F.

If you dont want to go this route, and just want to suplement the amylase that is presant in the malt... You could mash in and rest at your desired temp for 1 hour, then add ice to drop the temperature to 120, add AMG 300, and let that go for a while to finish the conversion.

One more note on adding enzymes, they are often very pH sensitive. I had poor results when I started because I was using my very alkaline tapwater, and the enzymes were not active at the pH of my mash. Now I use RO water and I pH adjust as needed. This was a major key to geting this to work for me...but my tap water is unusually alkaline.
 
Like Legume said, the AMG 300 is probably not the best at those higher temperatures. It is a good idea to have your water tested but, you could bypass it by using distilled or RO water. It would be a good idea to do a small test with it. PH does play a factor in enzyme activity.

Also, for that first mash, you didn't use near enough water. You had a total of 10.5# of grains. At a grist ratio of 1.5 qt/lb it would require 15.75 qts or about 4 gallons.
 
Like Legume said, the AMG 300 is probably not the best at those higher temperatures. It is a good idea to have your water tested but, you could bypass it by using distilled or RO water. It would be a good idea to do a small test with it. PH does play a factor in enzyme activity.

Also, for that first mash, you didn't use near enough water. You had a total of 10.5# of grains. At a grist ratio of 1.5 qt/lb it would require 15.75 qts or about 4 gallons.

I agree the water was off. The test batches were fine though, and the last one had a really nice hot cereal-like consistency.

I suspect the key is the amylase type. I did find what looks like an appropriate amylase, so that's on the way. If that doesn't help, then I'll do a pH test of the mash to see if that is way off.
 
I agree the water was off. The test batches were fine though, and the last one had a really nice hot cereal-like consistency.

I suspect the key is the amylase type. I did find what looks like an appropriate amylase, so that's on the way. If that doesn't help, then I'll do a pH test of the mash to see if that is way off.

What did you order and from where?
 
I malt my millet then kiln and roast according to my recipe so can't really say much about using enzymes to convert the starch. But I do use the enzymes that the malting make and to do this I grind the grain into flour and mash at 40cel then 55cel(I will change this soon to 60cel) then i remove almost a gallon of the liquid enzymes from the top of the mash and raise the temp to 75-85 to thicken the starch, cool and add the enzyme liquid back in and hold at 65cel for 90min. This gives a wort around 1.059 at 4 gallons and 1.035 at 5 gallons. The malting has been the learning curve but it not bad once you get some experince under your belt.
first batch was 2.7KG Pale millet, 250g Caramel Millet and 125g Munich millet all home roasted. Color was 6SRM and the recipe I used called for 38IBU. It was good but not what I wanted so I have changed this a lot from the first batch.
 
What did you order and from where?

Kato: it's called Termamyl. It's been mentioned before, but I only found the post today, and actually found out about it through my internet searching.

Can be ordered from Homebrewing.org, and also from Moonshinedistiller.com.

However, I received a great fact sheet from Grouse that I'm going to post separately, and they recommend something else, along with some other good advice.
 
Termamyl has only Alpha amylase activity, no beta amaylase activity.
It is most active at very high temps, and is denatured around boiling.
I use it during a 175 F rest.
It is great at helping to get starches gelatinized and chopped up into dextrines, but it is poor at chopping those dextrines into small fermentable sugars.
For choping your dextrines into fermentable sugars, somthing with Beta amylase activity would help...somthing like AMG300.

you might try your standard mash, with a little Termamyl added, then drop the temp and do a 120F rest with AMG 300.
 
I tried millet from Grouse Malting Company, it would not self covert, even with 1 tsp amalyse and 1 lb sweet potato per gallon, Did convert with adding some 6 row.
Then I tried some red millet from Colorado Malting co. Did add some Amalyse but self converted in 60 min at 153
From what I have read Millet gelatinization temperatures is well within normal mash temps. I do like to give it a protein rest as I found most GF malts are not fully converted

But from my experiments not all millet malt is equal.
For Colorado millet I give it a Protein rest at 124 for 20 min then a sacriffication rest at 154 with 1 tsp amalyse per gallon for 60 min and have not had any problem other then lots of turb.
Thou efficiency is low where it takes about 1.7 lbs millet to equal 1 lb barley to achive the same OG.
 
I tried millet from Grouse Malting Company, it would not self covert, even with 1 tsp amalyse and 1 lb sweet potato per gallon, Did convert with adding some 6 row.
Then I tried some red millet from Colorado Malting co. Did add some Amalyse but self converted in 60 min at 153
From what I have read Millet gelatinization temperatures is well within normal mash temps. I do like to give it a protein rest as I found most GF malts are not fully converted

But from my experiments not all millet malt is equal.
For Colorado millet I give it a Protein rest at 124 for 20 min then a sacriffication rest at 154 with 1 tsp amalyse per gallon for 60 min and have not had any problem other then lots of turb.
Thou efficiency is low where it takes about 1.7 lbs millet to equal 1 lb barley to achive the same OG.
Grouse recommends two amylase, beta and alpha, so that might be an option.

I looking for info on gelatinization temps for millet, it does look like different varieties have different gelatinization temps. As I recall, the variety used by Grouse was higher than some other varieties. With the right enzymes and pH range, I'm hopeful that even I can make this work. :)
 
Granule size also effects gelantization. So a finer grind will gel at a lower temperature. Even though Grouse says 163F, I think a finer grind will bring it down into the 150s.
 
I did my first, possibly last, all grain effort with terrible results.

Used:

7lbs pale millet, 1.5 lbs rice hulls, 0.5lb biscuit rice, 0.5 lbs crystal millet. Pretty fine grind, but not flour.

2.25 gal strike water at 180F, gave me a 162F mash. Seemed pretty dry; little in the way of spare water in it. Probably mis-measured, just seemed like it needed more. Anyway, I made sure there was some liquid under the surface, but something seemed off there.

Added about a quarter teaspoon of the AMG-300L amylase from Brewcraft. Label says this is for about 122F so suspect it does nothing at normal mash temps.

Failed iodine test at 90 minutes, also at 2 hours. OG of wort PRIOR to much sparging was only 1.02. After boiling down to 3 gallons, specific gravity was only about 1.03. Tossed the batch.

That's less than 1 qt/lb of grain. Without sufficient water the grain enzymes will not enter solution and convert the starches. What was your sparging method like?

I ran a couple tests on just one pound of millet, to try to get a decent OG. With one pound of millet, strike temp of 158F, direct fired to 165/166F, placed in thermal jug with about 1/8th teaspoon of AMG-300L, after 1hr and 40 minutes, OG of wort with sparge of half quart (at most) OG was 1.04. In a prior test, I skipped the temp rise to 166F, and just had a strike temp at 158F, with AMG-300L. Results were no better. Nothing passed iodine test. All efforts today looked cloudy, or starchy, although there was some sweetness to the wort.

You're not going to have any luck with 1 gallon tests. One problem is that you won't have enough grain to set up a proper filter bed to sparge, and BIAB style will lead to a lot of flour in your wort that may throw off your iodine tests. I'm confused about your temperatures. "Strike temp" means the temperature your water is at before you add the grain. How did you strike at 158 and mash at 166 without direct-heating a rise in temperature?

At 166 degrees, you will not get any amylase activity at all. 163 is pushing it for the upper range of alpha, but at 166 I'm guessing any activity you got happened during the rise.

I have a few thoughts: AMG-300L is not effective at these higher temps? I'm not able to hold the temps high enough for 90-120 minutes in an insulated container (temps were in the high 140s after 2 hours for my brewing effort. In the test, temps dropped to low 140s after 1 hour, 40 minutes). Despite Igliashon's success with a 158F mash, I may need to hold the grain at 165 for 15-20 minutes to gelatinize the grain?

Look, physics and chemistry don't work any different in your home brewery than they do in mine. I have mashed as low as 148 and still had successful conversion. There is no magic, I am using the same grains as you are. It works, period. You just need to get your water to grain ratio right and use an amylase that works at normal mash temperatures, rather than fermentation temperatures. EC Kraus Diatase was my go-to until I started ordering from Specialty Enzyme and Biotech. I use their SEBrew L-40 but can't say it works any different than the EC Kraus Diatase to be honest.

The problem you are having is that you attributed your first failure to too low of a temperature, when in fact it was severe lack of water and incorrect enzyme selection. You should have mashed even lower than you did, with almost twice as much water. The mash should have enough water that the malt will settle and leave an inch or two of clear wort on top. If it looks like hot cereal after the first 15-20 minutes, something is wrong.

The other problem is that you went on to try some 1-gallon tests thinking that you would get meaningful results from them. You used too high of a temperature, the wrong enzymes, and could not achieve stable temperatures or a decent filter bed to draw off clear wort.

If you insist on doing an unnecessary gelatinization step, add your enzymes AFTER you cool it down to 148-153 degrees. If you add them at a higher temperature you might as well pour them down the drain for all the good they'll do you, unless you are using termamyl, which is effective close to boiling temps (but mostly produces unfermentable dextrins, as it's for liquefying a cereal mash prior to addition to a mash).
 
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