Is My Mash Finished

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GAshinner
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Is My Mash Finished

Post by GAshinner »

When making a corn mash it seems impossible to use a hydrometer to measure potential alcohol. if i am making a real corn whisky with no added sugar then my hydrometer will not measure any potential alcohol until the malted barley converts the starch in the corn to sugar. I have a mash consisting of :

5Lbs cracked corn
1lb 2 row malt barlew
1tbsp amylyse enzyme
4tbsp distillers yeast.

the mash has been fermenting not for about 10 days and my hydrometer says the potential alcohol is zero but it said the same thing when i made the mash. I also tested with an alcohol meter and it says the Mash has no alcohol in it. Should i just run it? is there a better way to tell when a corn mash is finished?
Dnderhead
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Re: Is My Mash Finished

Post by Dnderhead »

Is it stopped working/bubbling? does it taste dry like dry wine?
I do not remember of a mash SG not changing, so a bit more info whould help.
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Re: Is My Mash Finished

Post by MuleKicker »

did you get good conversion? Did you do an iodine test or anything? did it bubble shortly after piching yeast? Like dnder said, what does it taste like?
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Re: Is My Mash Finished

Post by rad14701 »

What was the water volume and/or the total volume of the mash...???
GAshinner
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Re: Is My Mash Finished

Post by GAshinner »

the mash was 5 gal. Should i have got a pitential alcohol reading? how would i if the starch hasnt been converted to sugar yet?
WalkingWolf
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Re: Is My Mash Finished

Post by WalkingWolf »

GAshinner wrote:When making a corn mash it seems impossible to use a hydrometer to measure potential alcohol.
You can take liquid that collects on top (the converted starches and water) which are theoretically now sugar and water and measure the SG. While this measurement will not be an absolute it will be close enough for government work.
GAshinner wrote: . . . if i am making a real corn whisky with no added sugar then my hydrometer will not measure any potential alcohol until the malted barley converts the starch in the corn to sugar.
This part of your post makes me think you are looking at the measurement column on your hydrometer that is labeled Potential Alcohol % by Volume. Your statement is correct but I'm not sure you are taking all of the elements into account (my opinion :) ). The potential alc. % is based strictly on the measured specific gravity of the mash liquid. The pot. alc.% value will only be accurate with the starting specific gravity reading. The hydrometer is calibrated in relation to plain water. Water being 1.0. The measured rise in the SG is attributed to the "sugar" but in reality all of the other suspended solids in the wash will contribute to this measured elevation to some degree. For the home distiller the effects from "non-sugar" sources are considered inconsequential (except for RUM). To sum up the previous rambling you should concentrate on the specific gravity as this value will continue to be uitilzed to guage the progression of the wash. Also, as has been mentioned previously, you need to do the iodine test to test for full conversion of starches.

GAshinner wrote: . . . the mash has been fermenting not for about 10 days and my hydrometer says the potential alcohol is zero but it said the same thing when i made the mash. I also tested with an alcohol meter and it says the Mash has no alcohol in it.
With the above ingredient, even before conversion, you will get a measured elevation of the SG -- not necessarily accurate measurement of pot alc %. The alcometer is calibrated for distilled spirits and will not give an accurate reading unless used in distilled spirits.
GAshinner wrote: Should i just run it?
Yes. As RAD asked earlier, did it start fermenting when you added the yeast.
WalkingWolf
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Re: Is My Mash Finished

Post by WalkingWolf »

GAshinner wrote:the mash was 5 gal. Should i have got a pitential alcohol reading? how would i if the starch hasnt been converted to sugar yet?
Sorry GAshinner - I was typing up that manifesto :oops: when you posted this. I think you need to quit thinking about a potential alcohol percentage reading. Train your thought processes to concentrate on the specific gravity and what this reading tells you at a given point in the process. Before the ferment starts your reading will be the Initial Specific Gravity and with this you will also have a potential alc % value that corresponds with that SG. Once the ferment starts there will no longer be a potential alcohol percentage reading. By continuing to measure the SG through the ferment you will be able to track the progress of the fermentation. Most beginners washes should finish below 1.000.

It sounds to me you are relatively unfamiliar with your equipment and processes. To dramatically decrease your frustration level I would recommend you get a recipe out of the Tried and True and run 3 or 6 of these and you will be surprised how much you will learn with just these few runs. I may be incorrect and you may be a long time stiller but folks just starting out need to learn the ropes before jumping in to converting starches to sugars and such.

good stillin
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Re: Is My Mash Finished

Post by Samohon »

WalkingWolf wrote:
GAshinner wrote:the mash was 5 gal. Should i have got a pitential alcohol reading? how would i if the starch hasnt been converted to sugar yet?
Sorry GAshinner - I was typing up that manifesto :oops: when you posted this. I think you need to quit thinking about a potential alcohol percentage reading. Train your thought processes to concentrate on the specific gravity and what this reading tells you at a given point in the process. Before the ferment starts your reading will be the Initial Specific Gravity and with this you will also have a potential alc % value that corresponds with that SG. Once the ferment starts there will no longer be a potential alcohol percentage reading. By continuing to measure the SG through the ferment you will be able to track the progress of the fermentation. Most beginners washes should finish below 1.000.

It sounds to me you are relatively unfamiliar with your equipment and processes. To dramatically decrease your frustration level I would recommend you get a recipe out of the Tried and True and run 3 or 6 of these and you will be surprised how much you will learn with just these few runs. I may be incorrect and you may be a long time stiller but folks just starting out need to learn the ropes before jumping in to converting starches to sugars and such.

good stillin
WalkingWolf
+1 WW... Old timers never had the luxury of Hyrometers/Alcometers/Vinometers/Etc, instead they just used their senses... Once the convertion was done it tasted sweet and after the fermentation stage, it was bitter... I use a Hydrometer on my wash's, but I always taste, especially after fermenting on the grain...

@GAshinner...
If it started fermenting for you and it tastes bitter, then I would run it... As WalkingWolf said, the hydrometer will give you an approximation of the starting gravity/finishing gravity, due to all other compounds in the wort... From that you will be able to calculate approximately the abv in your wash, this will give you a heads up, allbeit limited, when you run it...

Hope this helps GAshinner.... :D
Let us know how you get on man... :D :D :D
♦♦ Samohon ♦♦

Beginners should visit The New Distillers Reading Lounge and the Safety and Related Issues among others...
goose eye
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Re: Is My Mash Finished

Post by goose eye »

it finished when the cap falls


so im tole
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Re: Is My Mash Finished

Post by rubber duck »

IF your sg was 0 I'm betting that your wash was so small that the grain/solids in the wash interfered with your hydrometer reading, because you took the reading in your fermentation bucket.

If you took the reading from a tube then you got 0 conversion.

Your right about a reading on a on grain ferment not being accurate but it will get you close.

As Goose says when the cap falls it's pretty much finished. I give it a additional 24 hours to clean up any leftover sugar and run it.
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Dnderhead
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Re: Is My Mash Finished

Post by Dnderhead »

Im thanking this is what happened.
you used 5 lb of corn , was this cooked? if not little/no conversion and no reading
10 day ferment,, the yeast/enzymes are "eating" at the starch,this make for a long slow ferment.
5 lb. of grain in 5 gal mash is about 3 1/2% (that is a in head estimate)
( this would not normally take 10 days.but if not cooked mite take months)
GAshinner
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Re: Is My Mash Finished

Post by GAshinner »

yes the mash was cooked. thanks for all of the replies. what do yall think about shaking or stiring the mash. will this help or should i leave it sitting alone undisturbed?
de`Canthas
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Re: Is My Mash Finished

Post by de`Canthas »

Although I am a novice at the art of distilling, I am a brewmaster and am very familiar with what exactly is happening during a grain fermentation.

Dnderhead is correct in saying that your wash should taste dry when it is done fermenting. This is because all of the sugars in your mash have been converted to alcohol.
MuleKicker wrote: did you get good conversion? Did you do an iodine test or anything? did it bubble shortly after piching yeast? Like dnder said, what does it taste like?
What MuleKicker is referring to is adding Iodine during the conversion process. Iodine fills the inside of the helix pattern that starch forms and causes a dark purple or black reaction. Short sugar chains do not form this coil and should not react with the iodine. Take a laddle and dip into your mash and place this on a plate. By adding one or two drops of Iodine to a plate of your mash, you can tell whether or not you have starches in your mash by whether or not the plate turns black/purple.

After you have converted our mash and pitched your yeast, you should have a significant amount of foam arise from the fermentation. This heavy foam cap is called the Krausen and lets you know the yeast are producing CO2. If you picthed your yeast at too high of a temperature and killed them (or if they never had any converted food to ferment), you may not have gotten a kick-start on your fermentation, and thus, no Krausen.

You should take a hydrometer reading from just liquid. Particulates in the mash may throw off your measurement if they sink, float, or stick to the hydrometer. At least in the beginning, you should always take a SG (starting gravity) when fermenting anything if you want to know how much alcohol is in it after fermentation.

I think I know these hydrometers you're referring to. They have SG (specific gravity), °P or °B (degrees Plato or Brix), and % potential alcohol. I believe the local home brew shop calls them "triple scale hydrometers." The first thing you should do is get a better hydrometer. These are small and are not very accurate. The larger your hydrometer, the more liquid is displaces and the larger the change in flotation from a change in density. This larger change equates to a higher resolution on your hydrometer. (I will post pictures of mine when I find my camera cord).

The only way to accurately determine the alcohol in your wash (other than Real Extract Analysis, which is beyond the scope of this forum), is to calculate based on the change in SG, °P, °B, or %pot.alc.. It should be obvious that the tool you are using (the hydrometer) is measuring specific gravity. The more carbohydrates in the solution (or anything, you can use hydrometers to determine the amount of salt in your aquarium), then the thicker the liquid and the higher the device floats. This drop in density signifies the sugars dissolved in the liquid being turned into CO2 and alcohol.

If you do a search for an alcohol calculator, you should find something that allows you to punch in your SG and FG (starting gravity and final gravity) to give you a % alcohol by weight or volume. This is also more accurate than using the %pot. alc. part of your hydrometer because your final gravity may vary greatly (it may be below 1.0000 SG / 0.0°Plato or you may have a stuck fermentation and it could be 1.010 SG / 2.5°Plato or even higher). The best solution is to get hydrometers that very accurately measure in SG or °P (degrees Plato). °P represents (very closely at low gravity) percent sucrose by mass. The formula for %alc. is much easier when dealing with changes in °P or °Brix versus changes in SG. Although °P or °B aren't a perfect multiple of specific gravity, usually .004 SG represents 1°P (so 1.040 SG would be 10°P, and 1.060 would be 15°P). Most brewers' s saccharometers have thermometers inside of the hydrometer to give a temperature correction. If your sample is colder than the hydrometer requires, the fluid will be slightly more dense, and the hydrometer will float higher and give you a higher SG (or °Plato). If it is hotter, the fluid will be less dense and the hydrometer will sink deeper into the sample and give you a lower reading.
GAshinner wrote: yes the mash was cooked. thanks for all of the replies. what do yall think about shaking or stiring the mash. will this help or should i leave it sitting alone undisturbed?
Stirring your mash may help to agitate some of the settled yeast and restart fermentation. However, if you did not have a proper conversion to begin with, you will not be able to ferment these starches. Also, continuous agitation during the entire course of fermentation can lead to higher fusel alcohols.
Samohon wrote:+1 WW... Old timers never had the luxury of Hyrometers/Alcometers/Vinometers/Etc, instead they just used their senses... Once the convertion was done it tasted sweet and after the fermentation stage, it was bitter... I use a Hydrometer on my wash's, but I always taste, especially after fermenting on the grain...

@GAshinner...
If it started fermenting for you and it tastes bitter, then I would run it... As WalkingWolf said, the hydrometer will give you an approximation of the starting gravity/finishing gravity, due to all other compounds in the wort... From that you will be able to calculate approximately the abv in your wash, this will give you a heads up, allbeit limited, when you run it...

Hope this helps GAshinner.... :D
Let us know how you get on man... :D :D :D
You should taste your mash after conversion to make sure it tastes sweet and that your starches in your grains have been converted to sugars. After fermentation, these sugars have been converted to alcohol and there should be no sweetness. The bitterness that Samohon is referring to is the tannins that have been extracted from the husks of the grain during fermentation.

I definitely agree that we are spoiled with technology when we can determine specific gravity to a 0.0001 resolution or temperature to 0.1°F with a device that cost under $100.00. People would have killed for that hundreds of years ago.

If you have already (supposedly) fermented your wash, then you can tell if there is alcohol in it by two separate tests. You must take a very accurate SG (specific gravity) reading and a refractometer reading. Usually the highest resolution hydrometers and refractometers for brewers/vinters/distillers measure in °Brix or °Plato. Because you have alcohol in your wash (hopefully), the readings for each device will be skewed (the hydrometer being lower because alcohol is lighter than water, and the refractometer higher because alcohol is more refractive than water) and should not give you the same numbers. By plugging these numbers into a very complex equation (just find a program called ProMash and use the %alc function) you can find the original specific gravity before fermentation (starting gravity) and the percent in alcohol by weight or volume.

My point is, you must have two of the following:
SG
FG
Refraction

to find % alcohol.
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Re: Is My Mash Finished

Post by rubber duck »

Good points de`Canthas, you obviously know what you talking about on the fermentation side of things. How would one account for the secondary conversion that occurs in a on grain ferment? What I'm getting at is additional conversion will take place during a on grain ferment, is there a way to factor this into Sg ,Fg formula?
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de`Canthas
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Re: Is My Mash Finished

Post by de`Canthas »

Good question.

I'm often intrigued when working with commercial distillers because they do ferment on grain--something brewers don't do because of the tannin extraction.

I understand that by fermenting on grain, you have longer for enzymes to attack residual starches for longer and more complete conversion. Brewers actually halt this process by running the sugar water off of the barley malt (this liquid is called the wort--prounounced "wert" or "vert" if you're German) into the kettle and boiling. The high heat disassociates the enzymes (breaks them down into their amino acid components). We as brewmasters are already getting almost every bit of starch hydrolized in the 45 or so minutes we mash. To me, a distiller could still get near perfect efficiency by simply not boiling his mash prior to fermenting. Someone please tell me if this is something commercial distillers do?
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Re: Is My Mash Finished

Post by rubber duck »

Generally commercial guys don't boil the wort/ mash prior to fermentation. Some of the new guys that are Brewery/ distilleries are doing their malt barely off grain and doing a pre ferment boil to the point of the hot break sometimes more to concentrate the wort.

In the case of this thread the ferment is on grain and no pre ferment boil as it would be done traditionaly by most distillers, commercial or not.

With a properly done on grain ferment a great deal of efficiency can be achieved and most of the starch can be converted to usable sugar.

Trying to pin down exactly what my mash abv is with out distilling it all out escapes me. I can pin it down aprox but to the letter...
Ideas are like rabbits. You get a couple and learn how to handle them, and pretty soon you have a dozen. John Steinbeck
de`Canthas
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Re: Is My Mash Finished

Post by de`Canthas »

Can't find the camera cord.... this room is as messy as a barn.

Here's a great link for the hydrometers I have. At work we have some that are even more specific (some of them are so accurate that each hydrometer only measures 1°). This particular site is a little overpriced. I'd check with Crosby and Baker possibly. Substitute Balling, Plato, and Brix interchangeably.
http://veegee.thomasnet.com/viewitems/p ... hermometer" onclick="window.open(this.href);return false;" rel="nofollow


On another note, do you perform your strip run on grain or do you Vorlauf it out?
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Re: Is My Mash Finished

Post by rubber duck »

If your just going to distill it I can't see a reason why one would Vorlauf it. My understanding of Vorlauf is that in beer making it 's the proses of recycling the wort through the grain bed until it goes clear. I don't see how this would be beneficial in distilling but I may be missing something, it's been known to happen. :) :)
Ideas are like rabbits. You get a couple and learn how to handle them, and pretty soon you have a dozen. John Steinbeck
de`Canthas
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Re: Is My Mash Finished

Post by de`Canthas »

Sorry, I used that word to describe running your wort off your grains. Lautering would have been more appropriate.
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Re: Is My Mash Finished

Post by rubber duck »

de`Canthas wrote:Sorry, I used that word to describe running your wort off your grains. Lautering would have been more appropriate.
Ahh now we're on the same page. I put my grain through a fruit press to extract all the liquid out. I don't like running on grain, it's difficult for me to run and I don't like dealing with boilers full of scalding corn slop.

But I'm taking to way off topic..

To tell when a all grain, on grain ferment is done wait for the cap to fall, at that point it's almost completely done. At this point it can be distilled, I like to give it one more day to clean up any leftover sugar.

To tell when a off grain ferment is finished a hydrometer can be used.

A hydrometer is a useful tool in determining to abv of a wort/mash but in the case of a on grain ferment it will only give a approximate abv. The actual abv may be a little higher because of the secondary conversion that happens to the grain in the fermenter.

If you have a Sg of 0 something went wrong.
Ideas are like rabbits. You get a couple and learn how to handle them, and pretty soon you have a dozen. John Steinbeck
de`Canthas
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Re: Is My Mash Finished

Post by de`Canthas »

Hey GAShinner, where are you located?

We're probably pretty close. You can borrow my hydrometers and refractometer.

PM me.
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