Amylase Question

[efddd]

I have never used amylase until today. Trying to do starch conversion on corn and it didn't work. I used tincture of iodine to check it and it is still purple after several hours. I added it at 140 degrees. Anyone have any ideas??

[BayouShine]

What temp did you cook your corn and for how long? Is it 100% corn or do you have other grains in the mash?

[zacwest52285]

As bayou said: corn cook time , crack of corn, temp of cook, gluco or alpha amylase how long did it stay at 140? Also should have used iodine on the corn before you even added the amylase ....

[BDF]

Alot of powdered amylase products out there only contain Alpha Amylase, in addition to this you need to have either Beta and/or Glucoamylase. Do you know the name of the maker of the enzymes you used?

Beyond that, how long did you cook the corn to release the starches?

[Jimbo]

Others here have answered with what is probably the problem, but Ill chime in anyway Corn is a mofo, unless you reground it super small, and cooked the living hell out of it, there will be starch remaining. Alpha should work on its own, just some of the dextrins will be unfermentable so when you ferment it it probably wont go drier than 1.015 roughly, depending on the SG.

I dont regrind cracked corn, but I do steep cook it for 3 hours in the 180's (boiling water poured over and wrapped up tight). Efficiency isint the best, but at $10 for 50 lbs, who cares.

[Woodpile]

I believe if iodine lands on grain it gives a false positive. If you ground your corn very fine, you might not ever get a clean iodine test. It would be different if you were sparging through a nice layer of barley husks.

What was your gravity? From the OP it only states your iodine test failed, not that you didn't have conversion.

I just did AG corn this weekend, myself, I am sitting at 1.066 and failing iodine test as well.

[Jimbo]

I just did AG corn this weekend, myself, I am sitting at 1.066 and failing iodine test as well.

yup, there ya go. This is why I love my refrac. just a drop needed for instant reading. its impossible to clear a whole cylinder of corn mash for a good reading.

[Woodpile]

I might be misunderstanding, but a refractometer would not show that conversion is complete, either. The point I was attempting to make is that the OP thinks his amylase is not working because of an iodine test. It may NEVER work in ground corn because it is not filtered through husks. Maybe if he strained a sample through coffee filter a few times there might be an answer; just guessing.

If you have 10lb of grain in 5 gallons of water and show 1.060 or higher (regardless of hydrometer or refractometer as a measuring tool), you have had some very good conversion.

Advice to OP - Take a look at a brew calculator (like Brewers Friend) e.g. 2 lb 2-row and 8 lb flaked corn in 5 gallons of water at 1.060 is = 75% efficiency. Your system is working well.

[skow69]

Also should have used iodine on the corn before you even added the amylase ....

Why?

[aj2456]

i found i just couldnt put any faith behind all alpha amylase- my mash didnt taste sweet just went really liquidated-

i now use alpha and beta (see enzyme mashing method thread) and the wort is nice and sweet- mind you i never did try to ferment an all alpha (i pitched/fermented it too hot and it went real bad) so it might work fine- but adding calcium chloride seems to really help

[Jimbo]

I might be misunderstanding, but a refractometer would not show that conversion is complete, either. The point I was attempting to make is that the OP thinks his amylase is not working because of an iodine test. It may NEVER work in ground corn because it is not filtered through husks. Maybe if he strained a sample through coffee filter a few times there might be an answer; just guessing.

If you have 10lb of grain in 5 gallons of water and show 1.060 or higher (regardless of hydrometer or refractometer as a measuring tool), you have had some very good conversion.

Advice to OP - Take a look at a brew calculator (like Brewers Friend) e.g. 2 lb 2-row and 8 lb flaked corn in 5 gallons of water at 1.060 is = 75% efficiency. Your system is working well.

I wasnt very clear woodpile. By 'there ya go' I meant , see you got a great conversion and still have starch. This is typical with corn. And the refrac comment,... with a refrac you can get a tiny sample of the goopy mess and confirm you got a good conversion. Very very hard to do wtih a hydro since the mash is too goopy.

[zacwest52285]

Also should have used iodine on the corn before you even added the amylase ....

Why?

I guess it does not really matter if the amylase is in when you check with iodine. If the iodine test comes back no good you cannot reheat the mash to gelanitization temp without killing the enzymes.

[Brendan]

Also should have used iodine on the corn before you even added the amylase ....

Why?

I guess it does not really matter if the amylase is in when you check with iodine. If the iodine test comes back no good you cannot reheat the mash to gelanitization temp without killing the enzymes.

The iodine test is to check whether all released starches have been converted to sugars. It just tells you if there is any starch left in the mash, not how much? I'm not sure what you're getting at, but you make it sound like you're testing for a quantity of starch, and then raising the temp to release more starches

Once you've added your enzymes and sat for conversion, your iodine test is just looking for full conversion of those starches which were already released...

[zacwest52285]

Brendan, I apologize, never using iodine myself I was wrong about the proper use of it.

My question now is this, is there an effective way to determine that you have made the majority of the starches available before adding your enzymes?

[Brendan]

Brendan, I apologize, never using iodine myself I was wrong about the proper use of it.

My question now is this, is there an effective way to determine that you have made the majority of the starches available before adding your enzymes?

That's a good question, and now we're getting out of my level of knowledge.

As far as checking immediately on the first batch, I don't know...after conversion I know how I went as I calculated the grain bill to get a certain amount of sugars. Then using the iodine test to check for full conversion, if I've hit my target SG, well then I know I released all the starches I planned to and converted them...and from then on for subsequent batches, well I have confidence in my quantities and times as it's been proven previously.

Doesn't answer your question I know, but I'm sure someone will chime in with a really simple answer

[Woodpile]

I wasnt very clear woodpile. By 'there ya go' I meant , see you got a great conversion and still have starch. This is typical with corn. And the refrac comment,... with a refrac you can get a tiny sample of the goopy mess and confirm you got a good conversion. Very very hard to do wtih a hydro since the mash is too goopy.

Ohhhh... now that makes perfect sense (forum responses can be tough).

As you mentioned, I really have no idea what that hydrometer is reporting now that I have softball sized blobs of corn mush circulating under their own gas-powered activity. I suspect it will settle at the end and be useful. From my winemaking experience I find that refracs lose accuracy as alcohol rises.

[Woodpile]

Brendan, I apologize, never using iodine myself I was wrong about the proper use of it.

My question now is this, is there an effective way to determine that you have made the majority of the starches available before adding your enzymes?

I would say, no. In homebrewing, one can test their efficiency, but that is done based on SUGAR recovered from a known quantity of grain & water. If they are waiting, I suspect there is a reason. How would you even know what the available quantity of starch is, anyway?

However, this is still just sugar-water. You can repeat the processes as many times as you want - you just need to add new enzyme each time your crank up the heat to work on the starches. The method I am working uses 2 conversion steps, with a temp rise in between (denaturing the enzyme). I experienced mid to upper 70s, so I am satisfied. I will make a small change to my method and look for improvements by trial and error from there.

[zacwest52285]

How would you even know what the available quantity of starch is, anyway?

There is no way to know available quantity of starch, that I know of. Iodine will allow you to see if the starches have been converted, but efficiency is still reliant on the available starches to the enzymes.

[woodshed]

How would you even know what the available quantity of starch is, anyway?

There is no way to know available quantity of starch, that I know of.

The only reliable one is experience. 10,000 hour rule ya know.

[zacwest52285]

Yep. I have not had a mash yet that fell too terribly fat from the mark, so I will keep trying different methods until I find the most effective.

[Jimbo]

I find that refracs lose accuracy as alcohol rises.

I dont know about that, theyre plenty accurate. But after fermentation starts you have to use a calcuator like the one linked here that factors out the alcohol. I have this bookmarked on my PC and my phone. http://www.northernbrewer.com/refractometer-calculator/" onclick="window.open(this.href);return false;" rel="nofollow

[skow69]

My question now is this, is there an effective way to determine that you have made the majority of the starches available before adding your enzymes?

I have been doing refractometer tests on the corn through the gelling process. I do not boil, but hold at 175f. The reading starts low and then increases. This is typical for a test every 15 minutes: 5 bx, 9, 12, 14, 15, 15.5, 15.5. I really don't know what the refrac is responding to, but using this as a guide, figuring that gelling is complete when it levels off, I have been getting very good yield from the corn. Or good for me, anyway. Last mash was 8# corn, 1# rye, 1# malt in 5 gallons water (plus enzymes). OG was 1.087.

[John Barleycorn]

Last mash was 8# corn, 1# rye, 1# malt in 5 gallons water (plus enzymes). OG was 1.087.

I undertand what you're saying about observing your gravity as you cook. But I don't understand how you would a get a higher OG from 10 lbs of grain than you would from 10 lbs of sucrose ... or is that higher reading due to the various solids in your wort?

[Jimbo]

Impossible to get 1.087 with 10 lbs grain in 5gal.

And refracs dont read starch they read sugar. So dont see how your refrac numbers grew during gel. I guess you meant during mashing, but you cant mash at 175, so I dont know what you were talking about.

[John Barleycorn]

A refractometer measures a refractive index, which is affected by the density of the sample. For our application the scale is just based on sucrose, but soluable solids will affect the density of the sample ... hence calibration with distilled water. So Skow's observations WRT increasing density don't surprise me ... just the OG. I would expect something closer to 1.060 ... maybe 1.065 or a tad higher if you did a good job.

So I'm just curious as to how cloudy the wort was when the measurement was taken.

[RandyMarshCT]

Impossible to get 1.087 with 10 lbs grain in 5gal.

Yeah, I'm pretty sure with 100% ME you'd only get 1.079 max. In my world, 100% ME doesn't exist... but, I've been proven wrong many times on these forums. I'm stoked with anything over 75%.

[Woodpile]

I obviously don't know, but it seems that implying a starch scale on a refrac is just guesswork. Sure, it is more dense, but that does not certify correlation.

Sure he showed 15.5 "starch BRIX", but that might equate to 1.030 under actual conversion. It would take a lot of test to build up a table. Frankly, probably not worth the time with a decent mash process. Furthermore, throw in 1/4 tsp enzyme with the yeast - now you have 10 days for it to continue work at low speed.

The proof is in the low wines - literally.

[John Barleycorn]

implying a starch scale on a refrac is just guesswork.

Agreed. But I didn't see that being implied anywhere ... only a guess that "gelling is complete when it [gravity] levels off".

That's not an unreasonable guess. Various viscographs for maize show similar behavior. It increases as the granules swell, reaches peak viscosity, then slowly rolls off as the granules burst. I realize viscosity and density are quite different. But we know that the viscosity drops off as the granules burst ... meaning more starch (and previously absorbed water) molecules are released into solution. Seems like a clever use of a refractometer to me.

[skow69]

or is that higher reading due to the various solids in your wort?

Could be. I take the sample from the thin layer on top, but I don't filter it. It was not clear.

Impossible to get 1.087 with 10 lbs grain in 5gal

You're right. That would be 42 ppg. Not possible. I hadn't calculated it. I must have measured wrong somewhere. The OG reading was from the refractometer. I didn't verify with a hydrometer. I usually get 1.060 - 1.065. I used a new fermenter. I prolly overstimated the water. And underestimated the corn. I'm not trying to be deceptive. But that was better conversion than I usually get. After 3 days fermenting it was down to 11.7 bx (from 21) for 8.2 ABV so I ran it. The alcohol content of the low wines verified the 8.2 wash.

And refracs dont read starch they read sugar. So dont see how your refrac numbers grew during gel. I guess you meant during mashing, but you cant mash at 175, so I dont know what you were talking about.

No, I was talking about gelatinizing the corn at 175f prior to mashing. I didn't claim the refrac was reading starch. I said I didn't know what it was responding to, but it has been consistent for three batches, now. Try it. That's why scientists publish their work, so their peers can replicate it (or not). I think John Barleycorn has prolly given us the explanation, But you have a refrac and you like bourbon. Let's see what you get.

A refractometer measures a refractive index, which is affected by the density of the sample. For our application the scale is just based on sucrose, but soluable solids will affect the density of the sample ... hence calibration with distilled water.

Makes sense to me. I have tried the same test with a hydrometer before and got similar results. I wouldn't post that because of the problems of sample thinkness and temperature calibration.

I obviously don't know, but it seems that implying a starch scale on a refrac is just guesswork. Sure, it is more dense, but that does not certify correlation.

Sure he showed 15.5 "starch BRIX", but that might equate to 1.030 under actual conversion. It would take a lot of test to build up a table. Frankly, probably not worth the time with a decent mash process.

I didn't imply any scale, make any correlation, or equate to any SG. I just noted a trend in the reading that has been consistent across trials. No values or units of measure. Do you have a refrac? Try it. Let's see what you get.

Various viscographs for maize show similar behavior. It increases as the granules swell, reaches peak viscosity, then slowly rolls off as the granules burst. I realize viscosity and density are quite different. But we know that the viscosity drops off as the granules burst ... meaning more starch (and previously absorbed water) molecules are released into solution.

I did not know that. Thank you.

[Jimbo]

1.060 to 1.065 with 10lbs of a corn recipe in 5 gallons is great conversion. I suspect youre using flaked, not cracked corn? Taht cracked shit is a mother, takes me something over 2.5 lbs per gallon with >50% cracked corn recipes to hit 1.060. 2.8lbs or so to hit 1.064 on last batch, but I dont worry too much about it since corn is so cheap. Were's talking pennys per fifth difference. Anyway, looks like youre getting great conversion skow.