Amylase Enzymes in Oatmeal, Rice, Etc.

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tscottii

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Hello All!
I'm new to this forum, but not to homebrew.
I've decided to branch out from my comfort zone and try using powdered amylase enzymes to convert starches in oatmeal, rice, etc. to fermentable sugars. The only problem is that I can't seem to make the conversion happen. I've made two small quart-sized trial batches of oatmeal (it is plentiful in our home), confirmed that starches are present via the iodine test, added the enzyme (1 teaspoon), and held the temps at 150F for one hour, but the iodine test still comes out jet black. Any suggestions as to what I'm doing wrong would be helpful. I've searched this rather extensive forum, but have not found the information I seek.
Thanks in advance.
 
Are you crushing the grains and cereal-mashing them first? How thick are you mashing? Are you stirring frequently during the rest?

Personally, I never had success mashing grains with just amylase, it was only when I started using Promalt (which has protease, cellulase, and glucanase as well as both alpha and beta amylase in it) that I started getting good conversion from unmalted grains. However, I know for a fact that Harvester successfully conducts mashes of oats, buckwheat, and chestnuts with just alpha amylase, the same kind readily available to homebrewers, so it can be done...I just don't really know the secret.

In any case, one thing I should mention: even using Promalt, I was never terribly impressed with the kind of flavors I was able to coax from unmalted grains. I did quite a few batches that way before switching to malted grains. Even using fancy exotic rices, buckwheat, etc., I always found the flavor very mild and not a significant improvement over using sorghum+rice extract with honey, candi syrup, and/or maltodextrin. Malting grains really does change their flavor profile and helps get that "malty" flavor that you just can't seem to get any other way. YMMV, but that was my experience.
 
Can you tell us more about what you're trying to achieve? Are you trying to convert your adjuncts to use in a extract brew?
 
As an introductory exercise, I used "quick" oats--oats that had already been gelantized. I put them in water and raised the temp to 160F. After the temp fell to 150F, I added the enzymes and held the temp at around 150--155 for an hour.
I'm beginning to wonder if the BSG enzymes contained both the alpha and the beta.
 
I want to convert their starches so they can be fermentable on their own--without the necessity of combining them with malted barley.
 
I did this with rice one time. I did a cereal mash and then mashed like you would with a normal batch, but with the amylase. Then I sparged, boiled, cooled and added yeast. It just looked like milky rice water for quite a while. I didn't think it was going to work, but I just added some amylase to the fermentor a day or two later, and it started working! It was really strange looking. It looked like as the amylase slowly worked through the milky starch water the yeast would go to work right behind it. It took a while to get going. I was pretty cool to watch. It just cleared from top to bottom, and eventually turned into a very pale yellowish rice "beer". I'd like to try it again sometime. I wanted to try something with oats and coffee. Anyways, that's how I got it to work.
 
I'm trying to take the starch that is present and available in the grains and convert them to fermentable sugars. It is my understanding that grains like "instant" rice and oatmeal are already gelatinized, and therefore those starches are readily available for conversion. Am I mistaken in this?
 
Maybe the pH is too high and outside of the enzymes' optimal ranges?

Even with just alpha-amylase you should end up with a negative iodine test, since it'll break down the starches into smaller and smaller dextrins the longer you let it go. That'll include fermentable sugars.
 
You're right about the "instant" rice and oatmeal. I was cheap when I did mine and bought a big bag of plain rice, and that's why I did a cereal mash.

I was just saying you should try adding it to the fermentor instead of mashing with it. It might take a day or two, but I think it'll work.
 
I suspect that I am not using enough of the enzyme and/or I'm not giving it enough time. I'll keep experimenting and keep everyone posted.
 
One possibility I hadn't considered is that maybe the powdered stuff has a different active temperature than naturally-occurring enzymes. IIRC most amylase sold on the homebrew market is for removing starches from wine, not for aiding in mashes with beer. The one exception I've found is EC Kraus's Diatase, which has both alpha and beta and is clearly meant to be used in a mash. But in any case, if the powdered stuff is meant for treating wine, it might have a lower operational temperature…I'd suggest checking with the manufacturer.
 
igliashon: that's a VERY good point. I was operating under the assumption that the enzymes would behave in the same manner as the enzymes in a mash, but the instructions on the container say to add "0.1 -0.3 teaspoon per gallon to convert starches into fermentable sugars." That would seem to indicate that this product is designed to be added AFTER the mashing process--or at least after the wort has achieved room temperature. Interesting. Thanks for the insight.
 
In other words, by sustaining a temperature of 150F, I might be inadvertently denaturing the enzymes. I'll keep you posted.
 
This says the temperature for fungal alpha-amylase tops out at 55C! Quite a difference from grain alpha-amylase. I am quite sure the powder you get from homebrew suppliers is of fungal origin.

http://www1.lsbu.ac.uk/water/enztech/maltose.html

That might explain why in my tests at mash temps with powdered alpha-amylase thinned out and liquified, but never got sweet. I had assumed the pH thing that I said above, but sounds like it's not going to be a problem.

Good luck.
 
I consulted the bible, and it says that the fungal alpha amylase is most active at 130F. I tried it at that temp and still had no conversion. I'll keep everyone posted.
 
I tried this again with rice. I prepared the rice by boiling the water and then putting the rice in for about an hour. Then I poured distilled water into the rice and stirred it around to get some nice starchy water.

image.jpg
 
It's still bubbling a little. I just took a taste and it's a little weak. I think next time I might have to adjust the cereal mash or just use instant. I'll let it sit a while longer and see what it tastes like when I bottle. It needs more flavor though.
 
It certainly cleared up a huge amount. I had the same effect when I used amylase in my secondary.

Almost looks like yellow Gatorade. I'm not sure you will ever get that much flavor from rice. Maybe add some toasted oats or buckwheat?

Let us know how this turns out.
 
I think you're right about rice not bringing much flavor to the table. I didn't really think about making a tasty recipe as much as I was testing the conversion. It worked really well at room temperature. I was wondering if the OP ever had any success with his experiments. If not I'd suggest adding the amylase at room temp along with the yeast. Oh, and add more amylase than the label suggests. I think it's generally used to clean up any left over starches in your brew or wine not for a complete conversion. So, more might be better. I don't know if there would be a difference with other adjuncts but I don't see why it wouldn't work.

I'll keep you posted on how it tastes. Maybe next time I'll come up with more of a recipe.
 
Well, I'm sad to say that this got dumped. It got some sort of infection and stunk like crazy. I think it happened when I was adding things for flavor. However, the amylase works. I think next time I would come up with a recipe instead of trying to fix the flavor later.
 
do you think this work with corn? did you check your Ph at mashing the starchy liquid?
 
I don't see why it wouldn't work. I've been wanting to try it with different adjuncts, but haven't really had a chance to get to it. I didn't check my PH. You should try it and let us know how it goes. I've thought about trying to do a small batch of chicha this way.
 
igliashon: that's a VERY good point. I was operating under the assumption that the enzymes would behave in the same manner as the enzymes in a mash, but the instructions on the container say to add "0.1 -0.3 teaspoon per gallon to convert starches into fermentable sugars." That would seem to indicate that this product is designed to be added AFTER the mashing process--or at least after the wort has achieved room temperature. Interesting. Thanks for the insight.
You're absolutely correct on this. I always add my amylase enzyme to the wash just before pitching my yeast. It works very well this way. However if you are going to ferment "off the grain" you can add it to the mash after you have held your temp for the recommended hour and it has cooled a bit
 
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