Conversion of Corn Starch to fermentable Sugar
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Conversion of Corn Starch to fermentable Sugar
Yesterday I weighed out seven pounds of cracked corn. Brought it to 170^f for one hour. Added one pund of 6 row at 150^f. Percet of potential ABV is only about 4%. What possibly went worng? I was expecting about 7-9 percent potentia ABV.
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Re: Conversion of Corn Starch to fermentable Sugar
dont know how much water but the corn needs to be cooked to 180f if not over.
- Still Water Run Deep
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Re: Conversion of Corn Starch to fermentable Sugar
180 for how long? How will I know it’s time to lower temp and add malted barley for conversion?
May Your Still Waters Run Deep
Justin
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Re: Conversion of Corn Starch to fermentable Sugar
Depends....the high temperature hold is to “gelatinize” the corn. The grind will determine how quickly the water is absorbed into the grain...finer grind will give a quicker gelatinization and a coarser grind will take longer. Plus, 185-190*F is a better target for the temperature hold.Still Water Run Deep wrote: ↑Sun Feb 09, 2020 8:09 am 180 for how long? How will I know it’s time to lower temp and add malted barley for conversion?
Get some high temperature enzymes to help with this process because at the corn meal gelatinized, it’ll turn into a porridge...like a thick muck. I find that holding the temperature steady for a couple of hours in the oven helps this process. The corn pudding will become like a “creamed corn” cornbread dough flavor and consistency. Enzymes help keep this stirrable...which is necessary to expedite the process.
How long to hold? ... until it tastes right (sweet and corny). Then, add water and bring the temperature down to 150*F. And stir in your malt. If you have gluco-amylase enzymes, add them now. Hold temperature at 145-148*F until the iodine test proves starch conversion is complete. This can take a while sometimes depending on the corn to malt ratio. So, conversion also is variable depending on the recipe and grind of the ingredients.
I hope this helps with your questions. Experience will help you too, so just get started, stumble and fumble, and soon you’ll know your processes and techniques.
ss
Last edited by still_stirrin on Sun Feb 09, 2020 8:47 am, edited 1 time in total.
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- Rumrunner
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Re: Conversion of Corn Starch to fermentable Sugar
The first time I did a corn mash it got to be a little sticky so I thought it was good, I thought this was the sticky mess mentioned by other distillers but I ended up with poor extraction like your describing. The second time I ground the corn much more finely and cooked it more and it turned in to a real serious mess. Way worse than the first one. So my advice to you would be:
1. 2# corn per gallon of water
2. Grind it up so there's some it's a little powdery like flour, like half powdery and half grits
3. Get your water up to a boil before adding the corn
4. Let it over 180 and keep stirring until it's a nasty sticky gelatinous mess
5. Let it drop to 150
6. Add malt
I think you're off to a good start, don't be discouraged, just cook it more next time. I'm a noob so I've got a lot to learn but my corn mashes get better each try and Im sure yours will too.
1. 2# corn per gallon of water
2. Grind it up so there's some it's a little powdery like flour, like half powdery and half grits
3. Get your water up to a boil before adding the corn
4. Let it over 180 and keep stirring until it's a nasty sticky gelatinous mess
5. Let it drop to 150
6. Add malt
I think you're off to a good start, don't be discouraged, just cook it more next time. I'm a noob so I've got a lot to learn but my corn mashes get better each try and Im sure yours will too.
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Re: Conversion of Corn Starch to fermentable Sugar
Ha! still_stirrin beat me to it!
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Re: Conversion of Corn Starch to fermentable Sugar
If you have no HT enzymes, you can 'pre-mash' your gelling corn with a bit of high DP malt (1/2lb), barley or wheat. At high temperature their enzymes denature quickly, but if you stir really good you'll get some thinning benefit out of them before they go. It'll save your arms later, especially at keg mash volumes.
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Re: Conversion of Corn Starch to fermentable Sugar
Hey guys, have a similar question regarding conversion of corn/grain starch.
My understanding has always been that sufficient amounts of amylase (from added amylase or from malted grains) in the mash will convert all the starch from any non malted grains (as long as the proportion is sufficient). However my guy at the homebrew supply is swearing to me that any non malted grains will not convert to sugars, regardless of what else is in there (thus non-malted rye or wheat included in the recipe would not convert, but would only add flavor etc). This seems wrong to me, but I wanted to touch base with the experts before moving forward (my experience is more fruit based, so I'm new to fermenting grains). Whats the answer?
My understanding has always been that sufficient amounts of amylase (from added amylase or from malted grains) in the mash will convert all the starch from any non malted grains (as long as the proportion is sufficient). However my guy at the homebrew supply is swearing to me that any non malted grains will not convert to sugars, regardless of what else is in there (thus non-malted rye or wheat included in the recipe would not convert, but would only add flavor etc). This seems wrong to me, but I wanted to touch base with the experts before moving forward (my experience is more fruit based, so I'm new to fermenting grains). Whats the answer?
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Re: Conversion of Corn Starch to fermentable Sugar
As long as unmalted grains are gelatinized before adding amylase, they will convert to sugar. Although keep in mind you will want gluco enzyme as well.
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Re: Conversion of Corn Starch to fermentable Sugar
That has not been my experience with mash grains, both malted and un-malted.. and it would sound by your statement that the guy has never experienced making whiskey beer, therefore his comment..
The starched of both grains do convert to sugars when the proper enzymes are used.. but one has to remember that malted grain will provide the conversion on it's own and at a lower temp, but the un-malted will not and require special enzymes and high temp mashing..
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Re: Conversion of Corn Starch to fermentable Sugar
Here’s a good read:
Have fun.
ss
Here’s how to improve your cereal grain extract:Most raw grains (unmalted) store their starches in granules which are not released simply by soaking them in water even in a single infusion mash. However within a certain range, the starch will “gelatinize” and lose much of its structure, allowing mash enzymes to later access these starches. This temperature range is called simply the “gelation” or “gelatinization” range. It varies slightly from plant to plant, but for most grains used in home brewing it falls within the range 120-140F (50-60 C). Flaking a grain or torrifying it (popping it) also gelatinizes the grain by breaking down its cellular structure through heat and pressure.
So raw grains that have not already been malted, flaked or torrified require a cereal mash step to gelatinize the starches before they can be broken down in the conversion step. Therefore a cereal mash uses at least two phases – one for “gelatinizing” the unmalted grains (called the cereal mash) and one for conversion of the sugars (i.e. the regular mash).
Here are some common gelainization temperature ranges:
Unmalted Barley: 140-150 F (60-65C)
Wheat: 136-147 F (58-64 C)
Rye: 135-158 F (57-70 C)
Oats: 127-138 F (53-59 C)
Corn (Maize): 143-165 F (62-74 C)
Rice: 154-172 F (68-78 C)
A lot to read. And a lot of effort to accomplish. But, you can become a better brewmaster and improve your yield, giving you more (better) product in the end. No cheater’s way around it...you’ll have to work at it. But it can be done....I do it all the time with unmalted grains.The process for performing the cereal mash phase is as follows:
Mill or grind your cereal adjuncts down into a fine grist – ideally smaller than your milled barley grains. Add about 20% of your total malted barley grains (i.e. Pale or Pilsner malt) to the cereal adjuncts. This malted barley will provide the enzymes needed to aid in converting and breaking down the sugars, as many cereal adjuncts don’t have sufficient enzymes by themselves.
Next add hot water at the rate of 2-3 quarts/lb (4-6 l/kg) to produce a fairly thin mash. This is a simple infusion, but you want to target the gelatinizing temperature ranges listed above depending on your adjunct. So if you are working with raw oats, for example, you need to be in the 127-138 F (53-59 C) range. Hold the gelatinization temperature ranfe for 20 minutes.
Slowly raise the temperature of the cereal mash up to a gentle boil and hold it for 20-30 minutes. As you do this the mash will go from a grainy mixture to a pretty sloppy gelatin mess that should coat the back of your spoon. When you reach the liquid goo phase, the cereal mash is good to go!
Finally add the gooey mixture into your main mash. If you are working directly with the hot liquid, you can often use a decoction calculator to figure out how high your starting mash temperature needs to be when adding the boiling cereal mash to hit your desired sugar conversion range – which is usually between 148-156 F (64-66 C). The other option is to use cold water to bring your cereal mash down to the target temperature before adding it to the main mash. After that you continue your conversion phase and sparge as you would with any regular all grain mash.
Have fun.
ss
My LM/VM & Potstill: My build thread
My Cadco hotplate modification thread: Hotplate Build
My stock pot gin still: stock pot potstill
My 5-grain Bourbon recipe: Special K
My Cadco hotplate modification thread: Hotplate Build
My stock pot gin still: stock pot potstill
My 5-grain Bourbon recipe: Special K
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Re: Conversion of Corn Starch to fermentable Sugar
Have your local store explain how a beer cereal mash works then. Same thing..Psilocide wrote:Hey guys, have a similar question regarding conversion of corn/grain starch.
My understanding has always been that sufficient amounts of amylase (from added amylase or from malted grains) in the mash will convert all the starch from any non malted grains (as long as the proportion is sufficient). However my guy at the homebrew supply is swearing to me that any non malted grains will not convert to sugars, regardless of what else is in there (thus non-malted rye or wheat included in the recipe would not convert, but would only add flavor etc). This seems wrong to me, but I wanted to touch base with the experts before moving forward (my experience is more fruit based, so I'm new to fermenting grains). Whats the answer?
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Re: Conversion of Corn Starch to fermentable Sugar
Cracked corn is too coarse for a no cook recipe.
You will need to grind the corn finer, bring it to a higher temp and keep that way for many hours or over night.
Using malt alone is a great exercise in doing things the old fashion way

But If you want to be successful and not get thirsty, High Temp Alpha is your friend

I noticed your doing small mashes
If you have an electric oven set it on low and mash in a large kettle.
What the temp, oven thermostats aren't noted for accuracy
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Re: Conversion of Corn Starch to fermentable Sugar
I believe you have "qualified" "your guy"

Option 1. One reason I like Jimbo's Easy Wheated Bourbon & Gumballhead so much is you don't have to cook your corn up a big batch of grits. Take a look at his procedure.
Option 2. Someone else will know if 1 pound of 6 row has enough D power to convert everything.
Otherwise, enzymes:
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Re: Conversion of Corn Starch to fermentable Sugar
Hey guys - thanks - I really appreciate all the detailed answers.
I know I'm going to make mistakes, but better to use experts knowledge to keep them to a minimum at least.
I'll be going forward, and definitely using the advice here.
I know I'm going to make mistakes, but better to use experts knowledge to keep them to a minimum at least.
I'll be going forward, and definitely using the advice here.