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General Category => All Grain Brewing => Topic started by: quest4watneys on March 14, 2011, 04:43:11 AM

Title: Water to grain ratio for mash tun.
Post by: quest4watneys on March 14, 2011, 04:43:11 AM
I've been inching towards all grain brewing and I'm trying to learn as much as I can so I have as much info as possible to make for a nice, stress free brew day (ha ha ha). I have noticed that John Palmer recommends as much as 2 qts. of water per 1 pound of grain but I've seen it as low as 1 qt. per 1 lb. What determines the actual amount? And has anyone heard of using glass marbles in a brew kettle to control boilovers? Should you add the strike water to the grain or the grain to the strike water? I'm sure I'll have a few more questions before I make the leap.
Title: Re: Water to grain ratio for mash tun.
Post by: tschmidlin on March 14, 2011, 05:20:28 AM
Re: water amount, anything in that range will be fine.  1 qt/lb will be rather thick, 2 qt/lb will be on the thinner side.  Mash thickness supposedly affects conversion, but I'm not convinced it makes a difference on a homebrew level.

You can add marbles to give nucleation sites during the boil, that might help.  I don't do it.  A big enough kettle and some anti-foam stuff works for me.

I add grain to water, but you can do it either way.  I direct fire my mash tun, so it makes sense for my equipment.

Feel free to ask questions :)  Go for all-grain sooner rather than later, once you try it you'll stop being so intimidated by the process.
Title: Re: Water to grain ratio for mash tun.
Post by: oscarvan on March 14, 2011, 08:01:35 AM
I'm at about 1.8 and that allows you to break the clumps up and get it all nice and stirred in just 20-30 seconds so you can stop the heat loss and put the lid on the thing. Wouldn't go much thinner
Title: Re: Water to grain ratio for mash tun.
Post by: Tim McManus on March 14, 2011, 08:18:25 AM
We usually dough-in with a .75 ratio just to saturate the grains.  Then we infuse and bring the ratio to 1.25 for a thick mash.  What determines the ratio is you.  As long as you are between 1 and 2, you'll be fine.  Over time you'll find the ratio that works best for your recipes / brewery.

Warm water goes into the tun and then the grain is added and stirred into the water.  We pour some grain in, stir a bit, pour some more, and stir until it all get in there and is wet.

I wouldn't put glass into a boiling kettle.  Ingesting a glass chip is a horrible experience, so I would be somewhat concerned about that.  We don't put anything in the kettle to control boilovers, however, we always have one hand on the gas flow valve for the burner.  Dropping the flame on the kettle manages boilover as do several other methods.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 14, 2011, 12:12:06 PM
I don't think glass beads or marbles are going to help control boilovers.  A boilover happens due to some protein being partially denatured and forming a thick floating foam.  Once it completely denatures it becomes more dense and sticks to the sides of the kettle.

I adjust my ratio so the grist fits in my MLT.  I have an MLT that is volume limited with big grain bills.  I've used everything from 1.25-2+  qt/lb and get pretty similar results.
Title: Re: Water to grain ratio for mash tun.
Post by: Hokerer on March 14, 2011, 01:30:59 PM
I generally adjust my ratio to balance first and second runnings. For example, I started figuring 1.5qts/lb for a batch this weekend but found that, by moving that to 1.78qts/lb, I'd get equal first and second runnnings (and no mash out).
Title: Re: Water to grain ratio for mash tun.
Post by: liquidbrewing on March 14, 2011, 02:29:48 PM
For boilovers, get yourself some food grade silicone.  A few drops right when it is going to boil reduces the foam and stops boilovers. 
Title: Re: Water to grain ratio for mash tun.
Post by: tschmidlin on March 14, 2011, 03:56:11 PM
I don't think glass beads or marbles are going to help control boilovers.  A boilover happens due to some protein being partially denatured and forming a thick floating foam.  Once it completely denatures it becomes more dense and sticks to the sides of the kettle.
There's two kinds of boilovers, the kind you're describing and the kind that comes from superheated wort that suddenly boils up as a huge bubble and spills over.  Marbles might help with the latter, not with the former.  I've also heard of people using pennies or a small piece of copper pipe for the same reason, plus it adds a little copper to the wort.
Title: Re: Water to grain ratio for mash tun.
Post by: morticaixavier on March 14, 2011, 05:07:55 PM
Is adding copper to the wort a desirable thing? if so why? just curious
Title: Re: Water to grain ratio for mash tun.
Post by: tschmidlin on March 14, 2011, 05:32:54 PM
It's an enzymatic co-factor required for yeast health.  It is unlikely to be an issue on a homebrew level unless you continually repitch your yeast and have no copper in your brewery.  But if you've got copper pipes in your house, chill with a copper chiller, etc, then there will be plenty of copper for the yeast.  And if you are getting fresh yeast from any of the yeast houses it's not something you need to concern yourself with.
Title: Re: Water to grain ratio for mash tun.
Post by: maxieboy on March 14, 2011, 05:46:34 PM
1.3 qts/lb has always worked well for me. Copper p/u tubes in HLT and BK.
Title: Re: Water to grain ratio for mash tun.
Post by: euge on March 14, 2011, 06:40:20 PM
I've settled on 1.6 qt per pound but that's not set in stone either.
Title: Re: Water to grain ratio for mash tun.
Post by: hopfenundmalz on March 14, 2011, 07:10:25 PM
Hey I used to always do 1.25 qt./lb.  Now I usually do 1.5 qt./lb., or even a little higher than that, as it stirs easier.

For really big beers, I might do 1.1 qt./lb. so it will all fit in the mash tun.  This will help you decide if you can get it all into your mash tun.  Go down to "Can I Mash It?"
 http://www.rackers.org/calcs.shtml
Title: Re: Water to grain ratio for mash tun.
Post by: tygo on March 14, 2011, 07:22:00 PM
What's the downside to going above ~2 qts lb?  pH?
Title: Re: Water to grain ratio for mash tun.
Post by: dzlater on March 14, 2011, 07:28:57 PM
I generally adjust my ratio to balance first and second runnings. For example, I started figuring 1.5qts/lb for a batch this weekend but found that, by moving that to 1.78qts/lb, I'd get equal first and second runnnings (and no mash out).
That's pretty much how I do it.
I figure my total water need divide by half, and if that's somewhere between 1 and 2 quarts per lb. I go with it.
I also only have a 5 gallon mash tun so I have to make sure it will fit, So sometimes I have to adjust for that too.
Title: Re: Water to grain ratio for mash tun.
Post by: mabrungard on March 14, 2011, 08:19:37 PM
What's the downside to going above ~2 qts lb?  pH?

Mash pH can be a problem if you're dealing with an alkaline water source.  There is only so much acidity provided by the grain bill and so much alkalinity from the mash water.  If you bump up the amount of water, you're also increasing the quantity of alkalinity and the mash pH will end up higher than it would if the water to grist ratio was thicker. 

Reducing the mash water alkalinity is one way to account for thinning the water to grist ratio.  Bru'n Water users have the capability to assess this effect and correct for it easily. 
Title: Re: Water to grain ratio for mash tun.
Post by: Hokerer on March 14, 2011, 11:50:47 PM
What's the downside to going above ~2 qts lb?  pH?

I'd think you'd also be driving the enzyme concentration too low
Title: Re: Water to grain ratio for mash tun.
Post by: quest4watneys on March 15, 2011, 02:46:53 AM
Would a nice cream stout be too ambitious for a first all grain?
Title: Re: Water to grain ratio for mash tun.
Post by: oscarvan on March 15, 2011, 03:01:00 AM
What's the downside to going above ~2 qts lb?  pH?

Can't give you the science, but was told the conversion process starts suffering if it gets too thin.
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 15, 2011, 03:16:18 AM
What's the downside to going above ~2 qts lb?  pH?
I'd think you'd also be driving the enzyme concentration too low
Nope.  I know brewers who regularly go over 3 qts/#.  Out of curiosity, I thought I'd give it a try.  So, I made a few batches of no sparge beer at over 3 qts/#.  The grain converted quickly and with very high efficiencies for no-sparge.  It also made delicious beer.

I have very soft water and I made amber and brown beers, which might have helped, but I had absolutely no pH issues or tannin problems.  I just finished a run of Lagers, all of which were mashed at 2-2.6 qts/#, and every one is clean, malty and everything I hoped they would be.

Supposedly, a thick mash can help with the low prevalence and poor stability of proteinases during a preotein rest.  I think intentionally mashing thick is mostly just a hold-over from the days of under-modified grain and brewers using mash tuns that were too small.  I don't know how it ever became seen as "best practice" for starch conversion among homebrewers,  
Title: Re: Water to grain ratio for mash tun.
Post by: tygo on March 15, 2011, 10:53:34 AM
What's the downside to going above ~2 qts lb?  pH?

I'd think you'd also be driving the enzyme concentration too low

The enzyme concentration might be a bit lower but the enzymes probably have been access to the starches in a thinner mash.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 15, 2011, 12:18:37 PM
I've seen reports of as much as 3qt/lb, I think that was from commercial breweries.  I don't think it would be a problem from a pH perspective unless your water was off-the-charts hard, nor an enzyme/conversion problem since your substrate and enzymes are present at 2/3 the level of the 2qt/lb and thats really not significant either.  Mostly it'd be a volume constraint for a homebrewer in some situations.
Title: Re: Water to grain ratio for mash tun.
Post by: mabrungard on March 15, 2011, 12:49:40 PM
  I don't think it would be a problem from a pH perspective unless your water was off-the-charts hard,

Lennie, hardness is a brewer's friend.  It's alkalinity that is the brewer's enemy.  Let's get in the habit of looking at alkalinity first and discussing its impact as our main criteria.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 15, 2011, 01:21:20 PM
 I don't think it would be a problem from a pH perspective unless your water was off-the-charts hard,

Lennie, hardness is a brewer's friend.  It's alkalinity that is the brewer's enemy.  Let's get in the habit of looking at alkalinity first and discussing its impact as our main criteria.


Sorry, used the wrong term.  Though I suppose theres a correlation between hardness and alkalinity?  I suppose the key is that you can have alkalinity without hardness.
Title: Re: Water to grain ratio for mash tun.
Post by: bluesman on March 15, 2011, 02:29:09 PM
As of lately I have been adding grain to water for ease of doughing-in. I aim for 1.5qts/lb for my mash thickness as it seems to give me good results and allows for a fairly loose mash. I have used 1qt/lb for large grain bills but my numbers have shown it to negatively affect the mash efficiency.

From my experience, anything 1.25-1.75qt/lb is the sweet spot (no pun intended) for the best mash efficiency.
Title: Re: Water to grain ratio for mash tun.
Post by: kgs on March 15, 2011, 02:56:33 PM
Would a nice cream stout be too ambitious for a first all grain?

My first AG was a stout. You're not worried about clarity or dry-hopping or anything like that, and stout is fairly forgiving. If it's a little bland after it ferments, there are numerous ways to doctor a stout with vanilla, coffee extracts, etc.

I also shoot for as close to 2 qts/lb as I can get in my 5-gallon mash tun. I add water to grain because it's much easier. I did it the other way once.

My only other suggestion is to limit your variables while you get used to AG (and yes, once you do you won't go back -- the beer just tastes better and the process is more interesting). In other words, if you're going to AG and you've always used dry yeast, don't decide this is the time to move to making yeast starters. Just my 2 cents.

Oh, and give yourself a nice full day.  Don't open your first homebrew until you've pitched your yeast. Clean everything as you go along. And consider organizing your ingredients:

http://www.flickr.com/photos/kgs/5528556074/
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 15, 2011, 03:13:14 PM
Would a nice cream stout be too ambitious for a first all grain?

For a dark beer, you may have to deal with water issues.  If you're prepared to deal with that, go for it.  Otherwise, something middle of the road like a pale ale may be a better choice.
Title: Re: Water to grain ratio for mash tun.
Post by: quest4watneys on March 15, 2011, 10:03:04 PM
Would a nice cream stout be too ambitious for a first all grain?

For a dark beer, you may have to deal with water issues.  If you're prepared to deal with that, go for it.  Otherwise, something middle of the road like a pale ale may be a better choice.

My water is definitely hard which is good for dark beers, correct? Any other water issues I should be worried about?
Title: Re: Water to grain ratio for mash tun.
Post by: bluesman on March 15, 2011, 11:11:16 PM
Would a nice cream stout be too ambitious for a first all grain?

For a dark beer, you may have to deal with water issues.  If you're prepared to deal with that, go for it.  Otherwise, something middle of the road like a pale ale may be a better choice.

My water is definitely hard which is good for dark beers, correct? Any other water issues I should be worried about?

Yes...typically "hard water" is good for brewing dark beers.
Title: Re: Water to grain ratio for mash tun.
Post by: quest4watneys on March 16, 2011, 02:51:15 AM
I certainly appreciate all the informed info! I'm now a couple of steps closer to AG :0) BTW, I'm now the proud owner of 3 nice, empty 1/2bbl SS kegs!  God I love Craig's List. I was looking for kegs for a month. Posted an ad on Craig's List last night at 9pm, had 3 kegs in the backseat of my car at 4pm today! The internet ROCKS!!!
Title: Re: Water to grain ratio for mash tun.
Post by: hopfenundmalz on March 16, 2011, 03:05:04 AM
Would a nice cream stout be too ambitious for a first all grain?
For a dark beer, you may have to deal with water issues.  If you're prepared to deal with that, go for it.  Otherwise, something middle of the road like a pale ale may be a better choice.
My water is definitely hard which is good for dark beers, correct? Any other water issues I should be worried about?
Yes...typically "hard water" is good for brewing dark beers.
It is more correct to say "alkaline" water is good for brewing dark beers.
 
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 16, 2011, 10:44:37 AM
What's the downside to going above ~2 qts lb?  pH?
I'd think you'd also be driving the enzyme concentration too low
The enzyme concentration might be a bit lower but the enzymes probably have been access to the starches in a thinner mash.
Right, enzyme concentration is probably rarely the limiting factor for most mashes.  Starch gelatization more apt to be limiting.  A thinner mash probably improves starch gelatinization.
From my experience, anything 1.25-1.75qt/lb is the sweet spot (no pun intended) for the best mash efficiency.
Did you actually have problems above 1.75 qts/#?  I never have.
Title: Re: Water to grain ratio for mash tun.
Post by: bluesman on March 16, 2011, 01:19:18 PM
From my experience, anything 1.25-1.75qt/lb is the sweet spot (no pun intended) for the best mash efficiency.
Did you actually have problems above 1.75 qts/#?  I never have.

I've mashed a few batches around the 2.0-2.3 range in the past with mixed results that I can't definitively point one way or the other to efficiency related issues. However there are some published experiments., I believe Kai can comment on the exact data that reflects some loss of efficiency with W:G ratios above 2.0.

Title: Re: Water to grain ratio for mash tun.
Post by: bluesman on March 16, 2011, 01:48:48 PM
I know this will eventually get Kai's attention. The following was taken from braukaiser.com. This experiment was conducted by Kai.

The chart gives the expected first wort extract/gravity based on the mash thickness at the time that the sample is pulled. To simplify the calculations this table assumes an 80% potential extract content in the grist (which is typical for most base malts) and 100% mash efficiency. Use these numbers as a benchmark for comparing your measured first wort gravities.
 

(http://www.braukaiser.com/wiki/images/3/3c/First_wort_gravity.gif)

I think that thinner mashes aid in better extraction of soluble sugars but I also remember reading about a thickness cutoff where there are diminishing returns.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 16, 2011, 05:26:38 PM
I guess you could take 0.5qt/lb of grain as your bound water, subtract that from the mash ratio, then multiply by the SG points to get your overall efficiency.  Otherwise its hard to see what the effect of increasing the mash water is.
Title: Re: Water to grain ratio for mash tun.
Post by: tygo on March 16, 2011, 06:18:10 PM
I think that thinner mashes aid in better extraction of soluble sugars but I also remember reading about a thickness cutoff where there are diminishing returns.

I'm sure there are diminishing returns.  You can only go so high on the efficiency.  But I don't see how decreasing the thickness could decrease your efficiency.  In my experience it's always been in the opposite direction but I haven't taken it to any extremes to see.
Title: Re: Water to grain ratio for mash tun.
Post by: bluesman on March 16, 2011, 06:35:48 PM
I think that thinner mashes aid in better extraction of soluble sugars but I also remember reading about a thickness cutoff where there are diminishing returns.

I'm sure there are diminishing returns.  You can only go so high on the efficiency.  But I don't see how decreasing the thickness could decrease your efficiency.  In my experience it's always been in the opposite direction but I haven't taken it to any extremes to see.

My wording is a little misleading here. There is certainly diminishing returns and the mash efficiency can be impacted by conversion. Practically speaking, mash pH is about the only thing I can think of that would impact the efficiency of a very thin mash. If there is a very large ratio of water to grain that would prevent the pH from adjusting to the targeted zone it could be detrimental to conversion.
Title: Re: Water to grain ratio for mash tun.
Post by: redbeerman on March 16, 2011, 06:42:50 PM
Dilution of enzymes may be a side effect of a thinner mash, thus decreasing efficiency as well.
Title: Re: Water to grain ratio for mash tun.
Post by: Hokerer on March 16, 2011, 06:46:51 PM
Dilution of enzymes may be a side effect of a thinner mash, thus decreasing efficiency as well.

...sounds familiar :)...

I'd think you'd also be driving the enzyme concentration too low

...although the responses were pretty generally against that as an issue.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 16, 2011, 07:01:39 PM
I don't recall going much above 2 qt./lb. but I didn't see any problems at that point that would indicate that the enzymes were too diluted.
Title: Is mash thickness calculated to include dead space?
Post by: wuertele on March 16, 2011, 07:35:17 PM
My MLT has a false bottom, and I have quite a bit of wort in the recirculation plumbing at any given time.  In fact, I have wort sitting about an inch above the grain bed that doesn't contact the mash until it drains into it.

When I calculate mash thickness, should I include *all* my wort (i.e. the volume of my strike water), or just the wort that is in contact with the grains?

If it is just the wort in contact with the grains, I would have to subtract out 2 gallons from my false bottom, a gallon or more for my plumbing, and about a gallon for the wort abobve the top surface of the grain.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 16, 2011, 08:38:49 PM
I guess you could take 0.5qt/lb of grain as your bound water, subtract that from the mash ratio, then multiply by the SG points to get your overall efficiency.  Otherwise its hard to see what the effect of increasing the mash water is.

I started to do the math and realized it'd be more accurate to judge the conversion by multiplying the qt/lb number by the first runnings points.  If you do that you see a slight increase in the total points converted over the range of 1qt/lb through 3.35qt/lb.  So there is obviously no decrease in conversion due to a thin mash and/or diluted enzymes.  Its another matter how much you can run off versus the volume left to sparge with, I think we can still assume that euqal runnings is something to shoot for there.  But for someone like me who is giving no-sparge a try, its comforting to know that I can add more water to the mash if I want.

For the record, 1.05 qt/lb gives 116 pts, and 3.35qt/lb gives 134 pts.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 16, 2011, 09:27:17 PM
I’ve been pretty busy and ran into this thread only now. Since I have done my fair amount of thinkering with different mash thicknesses, let me chime in.

Mash thickness and efficiency:

Based on my observations, thin mashed can convert faster and more complete compared to thick mashes. But that will only show up a difference when the thick mash didn’t achieve close to 100% conversion efficiency.

If the conversion efficiency between both mashes is the same a thin mash will have a better efficiency into the BK due to the larger amount of sparge water available in thick mashes. But that gain in efficiency is not necessarily good for beer quality.

Enzyme dilution:

The BIAB brewers have shown us that even in very dilute mashes the enzymes are not too diluted. You have to keep in mind the enzymes can also be inhibited by too much substrate or product (substrate inhibition) because their active sites get too crowded.

pH
mash pH is a function of distilled water pH of the grist, residual water alkalinity and mash thickness. In its simplest form it can be written as:

mash_pH = grist_pH + B*RA*R

(acid additions are reflected in the residual alkalinity for simplicity)
where B is a constant, RA is the residual alkalinity of the water and R is the mash thickness. You’ll notice that doubling R doubles the increase in mash pH over the distilled water pH of the grist, and you may be tempted to compensate a high RA with a low R (thick mash), but any water that you are not using in the mash you’ll be using during the sparge where it raises your sparge an then the boil pH too much. In the end you see that alkalinity is the problem and not mash thickness.

Personally I like using thin mashes where I use about 50-60% of the total water in the mash and the rest for sparging.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: richardt on March 16, 2011, 10:19:36 PM
Like KGS, I tend to fill my 10 gallon round Rubbermaid cooler with the grist, and then add the water.

Doing it the other way (i.e., adding the grist to the water in the cooler) raises two concerns for me:
1.)  I may not be able to get all the grist in the 10 gallon cooler

I tend to brew high-gravity brews and/or 10 gallon batches, so it is not unusual to see 7 or 8 gallons of dry grist filling the cooler before the water is added.

2.)  More enzyme damage may occur if I add the initial amounts of grist to the entire mash volume of hot water.

High initial "strike" temp of water in the mash cooler could have a disproportionate effect on the first addition of grist and lead to enzyme denaturation.  On the other hand, a quicker drop in strike water temp should occur if strike water is added to the entire amount of grist, and less damage occurs to the enzymes.

What say you?
Title: Re: Water to grain ratio for mash tun.
Post by: Will's Swill on March 17, 2011, 12:08:38 AM
I'd say that you'd not see much enzyme damage because you won't remain at high temp all that long even when adding grist to water.


If the conversion efficiency between both mashes is the same a thin mash will have a better efficiency into the BK due to the larger amount of sparge water available in thick mashes.


Was this a typo?  I would think that more sparge water would lead to higher efficiency so that if you see any effect at all it would be that thicker mashes are more efficient.  Or am I missing a secondary effect here?
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 17, 2011, 12:13:08 AM
Yes, that's a typo.

Thanks for catching that.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: jeffy on March 17, 2011, 12:18:25 AM
Like KGS, I tend to fill my 10 gallon round Rubbermaid cooler with the grist, and then add the water.

Doing it the other way (i.e., adding the grist to the water in the cooler) raises two concerns for me:
1.)  I may not be able to get all the grist in the 10 gallon cooler

I tend to brew high-gravity brews and/or 10 gallon batches, so it is not unusual to see 7 or 8 gallons of dry grist filling the cooler before the water is added.

2.)  More enzyme damage may occur if I add the initial amounts of grist to the entire mash volume of hot water.

High initial "strike" temp of water in the mash cooler could have a disproportionate effect on the first addition of grist and lead to enzyme denaturation.  On the other hand, a quicker drop in strike water temp should occur if strike water is added to the entire amount of grist, and less damage occurs to the enzymes.

What say you?

I say I have no enzyme issues by adding the grist all at once to the hot water in the mash tun.  Pour and stir, then check the temp.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 17, 2011, 12:56:29 AM
I say I have no enzyme issues by adding the grist all at once to the hot water in the mash tun.  Pour and stir, then check the temp.

Agreed.
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 17, 2011, 02:23:46 AM
If the conversion efficiency between both mashes is the same a thin mash will have a better efficiency into the BK due to the larger amount of sparge water available in thick mashes.
Was this a typo?  I would think that more sparge water would lead to higher efficiency so that if you see any effect at all it would be that thicker mashes are more efficient.  Or am I missing a secondary effect here?
One secondary effect is that a lot of brewers are limited, not by sparging efficiency, but by conversion efficiency.  It's really the only way to explain the less than 75% efficiencies that so many homebrewers report.  Mashing thin improves conversion efficiency which can give a lot of people a bigger gain, with a reduced risk of of oversparging, than increasing their sparge volume.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 17, 2011, 03:21:56 AM
I fully concur with that.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: tschmidlin on March 17, 2011, 06:36:00 AM
I say I have no enzyme issues by adding the grist all at once to the hot water in the mash tun.  Pour and stir, then check the temp.
I haven't notice any problems when I add half the grist to the hot water, stir, then add the other half.  This tends to happen when I do 10 gallon batches.
Title: Re: Water to grain ratio for mash tun.
Post by: oscarvan on March 17, 2011, 08:36:37 AM
FWIW.... Coleman 70 qt extreme.... 22 pounds of grist for most of what I brew, 10 gallons of water...=1.8 qt/g  All the grain in the cooler, all the water on top, cooler half full. Easy stirring, no spilling lots of room. Careful don't whack the thermometer. Nice soup close lid. RDWHAHB.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 17, 2011, 04:10:40 PM
I fully concur with that.

Kai

I concur also...I've seen it in my own brewing.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 17, 2011, 04:35:01 PM
Comparing conversion of 1qt/lb to 3.4qt/lb, the thinner mash increased converson by 16%.  2qt/lb was 9.5% more efficient.  This would definitely compensate for reduced sparge volume resulting from using a higher mash volume.  I'm not sure this aspect was included in the study that concluded that equal runnings were ideal.  I haven't seen that info.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 17, 2011, 04:48:34 PM
Comparing conversion of 1qt/lb to 3.4qt/lb, the thinner mash increased converson by 16%.  2qt/lb was 9.5% more efficient.  This would definitely compensate for reduced sparge volume resulting from using a higher mash volume.  I'm not sure this aspect was included in the study that concluded that equal runnings were ideal.  I haven't seen that info.

No, that aspect has not been included in that analysis and it cannot be included since conversion efficiency is not only a function of mash thickness but also a function of time, temperature, enzymatic strength, crush, mash profile, pH and the ones I forgot to list or don’t know about ;).

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: andyi on March 17, 2011, 04:57:28 PM
I need 7.75 gals to boil pot to get a post-boil 6gal batch (5.25 to the fermentor).  My mash ratio is around 1.7qts/1lb an that gives me roughly 50/50 on mash and sparg.

My efficiency is at 75%.  I am more concerned with consistency than max efficiency - also no dough balls.

Title: Re: Water to grain ratio for mash tun.
Post by: richardt on March 17, 2011, 05:07:24 PM
Thanks everyone. 

Stirring a thick 10-gallon mash filled to the brim in a 10 Gallon round Rubbermaid with a long plastic spoon is getting old.
Not to mention the long(er) lauters due to grain bed compaction if I over-crush.

I'm thinking there's a Coleman 70 qt extreme cooler-->mashtun on my list of things to ask for Father's Day.
It certainly might make my brewday more enjoyable.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 17, 2011, 06:29:54 PM
Comparing conversion of 1qt/lb to 3.4qt/lb, the thinner mash increased converson by 16%.  2qt/lb was 9.5% more efficient.  This would definitely compensate for reduced sparge volume resulting from using a higher mash volume.  I'm not sure this aspect was included in the study that concluded that equal runnings were ideal.  I haven't seen that info.

As Kai says, it wasn't taken into account, but if you'd like to read the data, it's here...

http://home.roadrunner.com/~brewbeer/files/nbsparge.html
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 17, 2011, 09:14:22 PM
Thanks Denny, I'd seen the link (I think you posted it) but it hadn't worked for me before.

Kai I'm not sure what you're saying.  Yes there are a number of variables that affect conversion efficiency, I think its reasonable to think that for a given set of conditions, a thinner mash would convert slightly better than a thick mash.  Maybe its not the case, I'm really not even sure why a thinner mash would give better conversion.  I wouldn't have predicted it.  It would be interesting to know the machanism, someone mentioned a postive effect on gelatinization and that seems reasonable.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 17, 2011, 10:13:37 PM
Maybe its not the case, I'm really not even sure why a thinner mash would give better conversion.  I wouldn't have predicted it.  It would be interesting to know the machanism, someone mentioned a postive effect on gelatinization and that seems reasonable.

This is what I have on this:

"But while thick mashes offer better protection for the enzymes, they also inhibit the enzymatic activity through the reduced availability of free water and the sugars acting as competitive inhibitors [Briggs, 2004]. In addition to that the gelatinization of starch is also slower and happens at higher temperatures in thick mashes and as a result thinner mashes are known to give more fermentable worts at normal mashing temperatures. " (source (http://braukaiser.com/wiki/index.php/Starch_Conversion#water_to_grist_ratio))

I would not have predicted it either and only after having seen a fairly dramatic effect in my mashing experiments did I start proposing the idea that thinner mashes can give you better efficiency.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: Will's Swill on March 18, 2011, 12:52:32 AM
Is this only under the assumption that you're not getting 100% conversion efficiency already?  I use 1 qt/# mash, 2 qt/# sparge and routinely get low 80's efficiency.  I fly sparge and I'm sure I could up that because I sparge with my 3/8" valves wide open, I figure my time is worth more than the lost efficiency.

I need 7.75 gals to boil pot to get a post-boil 6gal batch (5.25 to the fermentor).  My mash ratio is around 1.7qts/1lb an that gives me roughly 50/50 on mash and sparg.

My efficiency is at 75%.  I am more concerned with consistency than max efficiency - also no dough balls.



Wow, you're losing 12.5% of your extract to the kettle.  Why so much dead space?  Or is this loss to trub or something?
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 18, 2011, 10:55:45 AM
Is this only under the assumption that you're not getting 100% conversion efficiency already?  I use 1 qt/# mash, 2 qt/# sparge and routinely get low 80's efficiency.
Of course.  Mashing thinner isn't going to magically give you 120% conversion, but most brewers aren't hitting 100% conversion, IME.  In fact, since you mash so thickly and reserve more water for fly sparging, you might be making up for sub-optimal conversion by sparging more strenuously.  There's two extremes that will get you 80% efficiency.  One is to get 85% conversion and push lauter efficiency to 95%.  The second is to get 100% conversion and only push for 80% lauter efficiency.  The latter situation is more apt to produce superior beer.

It's popular to say, "I don't care about efficiency, I just want to make good beer."  Well, it's not about saving a couple bucks on grain; knowing your efficiency and how you achieve it can help you produce better beer.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 18, 2011, 11:54:14 AM
Of course.  Mashing thinner isn't going to magically give you 120% conversion, but most brewers aren't hitting 100% conversion, IME.  In fact, since you mash so thickly and reserve more water for fly sparging, you might be making up for sub-optimal conversion by sparging more strenuously.  There's two extremes that will get you 80% efficiency.  One is to get 85% conversion and push lauter efficiency to 95%.  The second is to get 100% conversion and only push for 80% lauter efficiency.  The latter situation is more apt to produce superior beer.

It's popular to say, "I don't care about efficiency, I just want to make good beer."  Well, it's not about saving a couple bucks on grain; knowing your efficiency and how you achieve it can help you produce better beer.

Well said.  I suppose "equal runnings" is a compromise that would mostly put you in the middle of the two extremes.
Title: Re: Water to grain ratio for mash tun.
Post by: bluesman on March 18, 2011, 02:56:20 PM
Well said.  I suppose "equal runnings" is a compromise that would mostly put you in the middle of the two extremes.

Finding the optimum ratio of mash/sparge water additions in an effort to maximize conversion/lautering efficiencies can be a daunting task but I've been aiming for 1.5qt/lb for mash thickness and following up with the required volume of sparge water to achieve my targeted kettle volume. I think that conversion should be given a little more weight than lautering efficiency, that's why I target 1.5qts/lb and add the balance for sparging. YMMV
Title: Re: Water to grain ratio for mash tun.
Post by: Will's Swill on March 19, 2011, 12:47:19 AM

There's two extremes that will get you 80% efficiency.  One is to get 85% conversion and push lauter efficiency to 95%.  The second is to get 100% conversion and only push for 80% lauter efficiency.  The latter situation is more apt to produce superior beer.


How does one result in a superior beer over the other (assuming you end up with the same amount of extract)?

Is a negative iodine test enough to confirm 100% conversion, or is some other test needed?
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 19, 2011, 01:36:20 AM

There's two extremes that will get you 80% efficiency.  One is to get 85% conversion and push lauter efficiency to 95%.  The second is to get 100% conversion and only push for 80% lauter efficiency.  The latter situation is more apt to produce superior beer.
How does one result in a superior beer over the other (assuming you end up with the same amount of extract)?

Is a negative iodine test enough to confirm 100% conversion, or is some other test needed?
The more strenuously you sparge, the more potentially undesirable compounds like polyphenols you'll extract.  Perhaps you've heard the word "oversparging" used to refer to this.

An Iodine test will only tell you if the already solubilized starches have converted.  Luckily, measuring conversion efficiency is even easier than an iodine test.  All you need to do is measure the gravity of the mash liquor and compare it to the mash thickness to know that you've fully removed all (or most) of the potential sugar from the grain.  Luckily, Kai's done the heavy lifting there, so you can use one of his tables:
(http://www.braukaiser.com/wiki/images/3/3c/First_wort_gravity.gif)
Title: Re: Water to grain ratio for mash tun.
Post by: Will's Swill on March 19, 2011, 02:18:14 AM
But a thinner mash would not result in more solubilized starch would it?  So your presumption is that a thicker mash means oversparging (given that the same total amount of water is used for strike/sparge in the thick and thin cases).  I acidify (acidulate?) my sparge water in an effort to prevent oversparging, but perhaps I'm in need of an experimental batch to see if there's a taste difference... :)
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 19, 2011, 04:02:56 AM
Thinner mashes seem to make it easier for the extract to be extracted from the grain. How exactly, I don't know, but i have a few ideas.

However, thin mashes are not required to get close to 100% conversion efficiency. Let's not forget that. If you haven't tried mashing thin and you are looking for something new to try, go for it. 

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: beveragebob on March 19, 2011, 08:51:37 AM
Awesome thread. Being a "continuous" or fly sparger with adequate space in my kettles I've always used the ROT that one should not go lower on the mash side of 1:1 ratio of MT water to HLT "sparge water"

btw and not to hijack the thread....is Ken Schwartz still around in the homebrewing scene somewhere?Just wondering.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 19, 2011, 02:18:46 PM
btw and not to hijack the thread....is Ken Schwartz still around in the homebrewing scene somewhere?Just wondering.

He mentioned in an email some years back the he's no longer active in brewing.  IIRC, his website even disappeared for a while, but he put an archival version back up.
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 20, 2011, 04:56:37 PM
But a thinner mash would not result in more solubilized starch would it?  So your presumption is that a thicker mash means oversparging (given that the same total amount of water is used for strike/sparge in the thick and thin cases).
Sorry for the slow reply, It's been a brutal week at work... Anyway,

Yes, for some brewers, thinner mashes may result in more starch gelatinization, which is synonymous with more solubilized starch.  But, yes, mashing thinner is not required to get 100% conversion efficiency, but it helps a lot of brewers who are having trouble getting good conversion efficiency.

No, I'm not presuming that a thicker mash means oversparging.  What I'm trying to say is that, without measuring your conversion efficiency, you don't know whether you are achieving the efficiency through good conversion or strenuous sparging.  Generally, pushing gravity higher by sparging would be considered less desirable than by conversion.

Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 20, 2011, 08:55:13 PM
All this talk of mashing thin got me curious to try it for myself.  Today I mashed two small 5lb batches of a Vienna lager grist, 2lb pils, 2lb Vienna, 1lb light Munich.  On the first I used a 3qt/lb mash ratio and got 75% efficiency preboil.  On the second I used 3.2qt/lb and also got 75%.  I mashed at around 150F for two hours in each case, then just drained and boiled.

I did two batches because I inadvertantly added double the hops to the first batch, so my solution was to make another with no hops to get the intended IBUs.  Poor reason, but replicating an experiment is sound science.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 21, 2011, 12:52:52 AM
Lennie,  did you see a change in efficiency compared to your usual procedure?

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: gmac on March 21, 2011, 03:28:53 AM
All this talk of mashing thin got me curious to try it for myself.  Today I mashed two small 5lb batches of a Vienna lager grist, 2lb pils, 2lb Vienna, 1lb light Munich.  On the first I used a 3qt/lb mash ratio and got 75% efficiency preboil.  On the second I used 3.2qt/lb and also got 75%.  I mashed at around 150F for two hours in each case, then just drained and boiled.

I did two batches because I inadvertantly added double the hops to the first batch, so my solution was to make another with no hops to get the intended IBUs.  Poor reason, but replicating an experiment is sound science.

Is this right?  3qt/lb for the first, 3.2 for the second?  I would think that 0.2 qt/lb wouldn't really be the difference between thick or thin.
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 21, 2011, 11:05:29 AM
On the first I used a 3qt/lb mash ratio and got 75% efficiency preboil.  On the second I used 3.2qt/lb and also got 75%.
Is this 75% with No-Sparge?  That's about what I see mashing thin without a sparge, depending on the amount of grain.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 21, 2011, 01:12:11 PM
Lennie,  did you see a change in efficiency compared to your usual procedure?
Kai
Kai, with my "conventional" 1.5-2qt/lb and a batch sparge, I'd get anywhere from 75-80% typically.  If I mashed at 2qt/lb I'd drain off 1.5qt, that should give me 75% right there.  A sparge would bring me to 90% theoretically.  I have almost no dead space in the tun and I drain it thoroughly.  I have to attribute my results as coming from differences in conversion.  I seem to be losing upwards of 10% of my sugar in the thicker mash.  This is in spite of my fairly fine crush and extended mash time.  I did see another 5% when I started doing a short beta rest/mashout so I knew I was leaving some behind.  The beta rest gives me a less dry beer though so its not a universal way of improving my efficiency.  Decoction also worked and I could get a dry product with this method but its more work.

Is this right?  3qt/lb for the first, 3.2 for the second?  I would think that 0.2 qt/lb wouldn't really be the difference between thick or thin.

These were both thin, they were replicates not a control and an experiment.  I only did 3.2 so I wouldn't need to add additional water to the kettle.
On the first I used a 3qt/lb mash ratio and got 75% efficiency preboil.  On the second I used 3.2qt/lb and also got 75%.
Is this 75% with No-Sparge?  That's about what I see mashing thin without a sparge, depending on the amount of grain.
Yes I mashed with all my water, then just drained and boiled.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 21, 2011, 01:40:58 PM
Quote
Kai, with my "conventional" 1.5-2qt/lb and a batch sparge, I'd get anywhere from 75-80% typically.  If I mashed at 2qt/lb I'd drain off 1.5qt, that should give me 75% right there.

Lennie, I’m running these numbers (1 lb , 2 qt) through my batch sparge simulator (http://braukaiser.com/wiki/index.php/Batch_Sparge_and_Party_Gyle_Simulator) and I’m getting only 68% on the 1st run off (assuming 0.12 gal/lb absorption). The run-off volume is 1.5 qt. It also assumes 100% conversion efficiency.

To make a ~ 12Plato beer with 15% boil-off I have to add 1.2 qt/lb sparge water. This additional batch sparge bumps efficiency by ~20 points to 88%. In the end you get 2.7 qt @ 10.3 Plato pre boil wort.

With 0.1 gal/lb grain absorption, I get 72% efficiency with the first runnings and 90% if you combine both 1st and 2nd runnings.


Quote
I seem to be losing upwards of 10% of my sugar in the thicker mash.  This is in spite of my fairly fine crush and extended mash time.  I did see another 5% when I started doing a short beta rest/mash-out so I knew I was leaving some behind.  The beta rest gives me a less dry beer though so its not a universal way of improving my efficiency.  Decoction also worked and I could get a dry product with this method but its more work.

You may want to fill out portions of the efficiency spreadsheet (http://braukaiser.com/documents/efficiency_calculator.xls). I’m using this on almost every batch to calculate my efficiencies since it also corrects for temperature and can tell me what boil-off I need to aim for to get my target gravity. It also tells me how much conversion efficiency I’m getting. If I’m still well below 100% I tend to give the mash more time or raise the mash temp. I know that if I don’t take care of that problem right there I’ll likely miss my target gravity.

Do you happen to have a record of your first wort gravities? That and mash thickness is what you’ll need to calculate conversion efficiency.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 21, 2011, 04:26:47 PM
I see, I was just going by my own simplified version of an efficiency calculation.  I use 0.125gal/lb (0.5qt/lb) absorption.  I don't have first runnings measurements, I haven't been taking those since I've had consistent results that I thought were adequate as far as sugar recovery.  Since I'm getting something similar with this 3+qt/lb method I might continue with it for the time being, just to see if theres a difference in beer quality.  It would seem that it could only help, not hurt, and its easier to just heat water once and then run it all off.  The few points difference between this and batch sparging, doesn't seem to make a huge difference.

I thought my 75-80% efficiency was pretty typical for a batch sparge.  It always made me wonder why I wouldn't get closer to the 88% you've got as a predicted amount, I think incomplete conversion is the most obvious answer.  I've let the mash go for two hours before and still only get my usual efficiency.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 21, 2011, 04:50:31 PM
I played with your calculator a bit.  it looks like with my conventional 2qt/lb batch sparge I'm probably getting in the range of 83-88% conversion.  With the 3qt/lb it looks like I got 95% conversion.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 21, 2011, 06:31:50 PM
I thought my 75-80% efficiency was pretty typical for a batch sparge.  It always made me wonder why I wouldn't get closer to the 88% you've got as a predicted amount, I think incomplete conversion is the most obvious answer.  I've let the mash got for two hours before and still only get my usual efficiency.

Lennie,

The good thing is that you have something that works. Over the next few batches you can take a few more measurements to figure out where your losses are. Then you can decide if it is worth doing something about these losses.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 21, 2011, 07:19:37 PM
True, things are quite predictable.  I''ve always wondred why I'd get 75% efficiency when a simple two step extraction would suggest a higher recovery.  Now I know its got to do with conversion being product inhibited.  I found an article on product inhibition of alpha-amylase that says its 50% inhibited by 100g/L.  A 1.046 wort is 120g/L.  Plus theres temp degradation of the enzyme so you just can't leave it to mash for hours and get complete conversion.

http://www.springerlink.com/content/n17r1h56h2681251/
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 22, 2011, 10:41:02 AM
I''ve always wondred why I'd get 75% efficiency when a simple two step extraction would suggest a higher recovery.  Now I know its got to do with conversion being product inhibited. 
Well... that's certainly a factor, but these days I can get close to 100% Conversion Efficiency with a No-Sparge or a Batch Sparge, so it's not an absolute. 

For a 12°p beer, my real-world numbers give me ~75% Mash Efficiency by No-Sparge with a 3 qt/# mash (or a 2 qt/# mash and an added alpha-amylase rest at 3 qt/#, which can be slightly more efficient for me), or 87% from a 2 qt/# mash and a Batch Sparge.
Title: Re: Water to grain ratio for mash tun.
Post by: tomsawyer on March 22, 2011, 11:52:16 AM
Well... that's certainly a factor, but these days I can get close to 100% Conversion Efficiency with a No-Sparge or a Batch Sparge, so it's not an absolute.  

For a 12°p beer, my real-world numbers give me ~75% Mash Efficiency by No-Sparge with a 3 qt/# mash (or a 2 qt/# mash and an added alpha-amylase rest at 3 qt/#, which can be slightly more efficient for me), or 87% from a 2 qt/# mash and a Batch Sparge.

Whats the secret?  And how do you calculate conversion?  Everything soluble converts so the iodine test seems to me to be slightly misleading.  And, do you find any qualitative differences between the beers?  Assuming you can hit similar OG/FG with the two processes.

Next time I do one of these I'm going to use 3.7qt/lb which will give me full preboil volume, and I'm going to check the progression of the conversion every fifteen minutes with a refractometer.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 22, 2011, 02:07:09 PM
Lennie, here is something about calculating conversion efficiency:http://braukaiser.com/wiki/index.php/Troubleshooting_Brewhouse_Efficiency#Determining_Conversion_Efficiency

extract that has not contributed to conversion efficiency tends to be still bound in the grits of the mash.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 23, 2011, 12:38:33 AM
Whats the secret?  And how do you calculate conversion?  Everything soluble converts so the iodine test seems to me to be slightly misleading.  And, do you find any qualitative differences between the beers?  Assuming you can hit similar OG/FG with the two processes.
I don't think there's a magic secret to getting full conversion.  The biggest factor is crush, but a warm alpha rest and a thinner mash can push that last reluctant 10% or so to convert or help make up for a less than optimal crush.

The calculation for conversion efficiency is a little bit of a pain, because of the volume contribution from the sugar.  The easiest way is to use Kai's chart that shows the gravity of the first runnings for a given mash thickness at 100% conversion:
(http://www.braukaiser.com/wiki/images/3/3c/First_wort_gravity.gif)

I find the iodine test to be just this side of useless.  It certainly won't tell you if you have complete conversion.

As far as qualitative differences, I do get different OGs, of course, but I guess that's quantitative.  Other than that, I've been using No-Sparge for Lagers and British Ales, and I get a nice malty but soft malt profile, which is why I chose to use that technique, but I've never made the same recipe both ways to make the comparison.  I don't expect there's a huge difference in flavor, though.  More than anything else, it's just a little easier and a little faster than bothering to sparge and, at 75%, it only costs 1 # of extra grain for 5 gallons of a 12°p beer.
Title: Re: Water to grain ratio for mash tun.
Post by: oscarvan on March 23, 2011, 01:36:48 AM
I taste the wort..... I know not very scientific. But it does tell me there's a metric crap load of sugar in there, and in the "artisan tradition" that's close enough.
Title: Re: Water to grain ratio for mash tun.
Post by: tygo on March 23, 2011, 01:52:14 AM
a metric crap load of sugar

How many degrees Plato is one metric crapload ?  ;D
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 23, 2011, 02:04:52 AM
Since I wrote those efficiency articles I have come up with a better formula for CE that doesn't go though the table Malzig mentiones. Though the table is still useful to get an idea how stong of a FW one can get.

CE = extract potential * (100 – Plato) / ( Plato * R )

where
* extract potential is the grain's extract potential in %. This needs to be the "as is"  extract potential that includes the moisture content i.e DBFG * (1-1/MC) . DBFG - dry basis fine grind extract in %, MC - moisture content in %. 80% is a good estimate for the "as is" extract potential.
* Plato is the mash wort strength in Plato
* R is mash thickness in l/kg

These calculations are best done with metric values and under the hood my spreadsheet does everything with Plato and metric units.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: oscarvan on March 23, 2011, 02:24:02 AM
a metric crap load of sugar

How many degrees Plato is one metric crapload ?  ;D

Hot, very hot.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 23, 2011, 03:19:58 PM
I find the iodine test to be just this side of useless.  It certainly won't tell you if you have complete conversion.

It's amazing how this fallacy has perpetuated itself through the years.  Between the high possibility of false readings and the lack of useful info, I tell new brewers to just forget the iodine test even exists.
Title: Re: Water to grain ratio for mash tun.
Post by: Kaiser on March 23, 2011, 04:43:45 PM
I find the iodine test to be just this side of useless.  It certainly won't tell you if you have complete conversion.

It's amazing how this fallacy has perpetuated itself through the years.  Between the high possibility of false readings and the lack of useful info, I tell new brewers to just forget the iodine test even exists.

While a negative iodine test doesn’t tell you that you are done mashing a positive test at the end of mashing shows that your mash didn’t go as planned.

Kai
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 23, 2011, 04:47:09 PM
I agree, Kai, but I've also seen so many false positives after people have mashed for hours that I just don't see the value of the test.
Title: Re: Water to grain ratio for mash tun.
Post by: Will's Swill on March 25, 2011, 12:38:44 AM
Yikes!  No wonder you responded the way you did to my post about the 6 hour mash.  What is iodine reacting with to cause a false positive if not unconverted starch? 

As a side note, I do little mini mashes on the kitchen stove for my yeast starters.  One time I was getting false positives from some starchy deposit on the plate I was using for the sample test.  That makes you slap your forehead.
Title: Re: Water to grain ratio for mash tun.
Post by: oscarvan on March 25, 2011, 12:37:58 PM
Never done an Iodine test.....always meet my OG, or close.....
Title: Re: Water to grain ratio for mash tun.
Post by: euge on March 25, 2011, 04:48:59 PM
Never done an Iodine test.....always meet my OG, or close.....

I did the very first AG batch. But it was about 30 minutes in, showed conversion. I left it at that- never did it again. If one's mash is not converting then there's a serious problem. What it would be I don't know, cause it's never happened to me.
Title: Re: Water to grain ratio for mash tun.
Post by: malzig on March 26, 2011, 02:13:43 PM
I suppose the iodine test might be very meaningful to breweries like Budweiser, who are trying to convert a boatload of rice.
Title: Re: Water to grain ratio for mash tun.
Post by: oscarvan on March 26, 2011, 02:59:38 PM
I suppose the iodine test might be very meaningful to breweries like Budweiser, who are trying to convert a boatload of rice.

Yes, and every drop of sugar counts to them......

Me, heck at $0.65 a pound I am so far ahead of decent beer prices I don't really care about a point or two.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 26, 2011, 03:59:10 PM
Yikes!  No wonder you responded the way you did to my post about the 6 hour mash.  What is iodine reacting with to cause a false positive if not unconverted starch? 

It is reacting with small pieces of malt that have been gelatinized and converted.  I've seen it happen many times.  If you mashed for 6 hours, unless there was something REALLY screwed up, you converted about 4 hours earlier.
Title: Re: Water to grain ratio for mash tun.
Post by: denny on March 26, 2011, 03:59:55 PM
I suppose the iodine test might be very meaningful to breweries like Budweiser, who are trying to convert a boatload of rice.

I'm sure they have far more scientific and accurate ways to test.
Title: Re: Water to grain ratio for mash tun.
Post by: Will's Swill on March 26, 2011, 11:09:49 PM

It is reacting with small pieces of malt that have been gelatinized and converted.

If it's been converted, why would it react?