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Thick vs Thin Mash

Wildrover

Grandmaster Brewer
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I was watching the latest basic brewing video where they were talking about mash thickness and how a thinner mash (2.0 qts of water per lb of grain as opposed to 1.25) will provide greater efficiency. 

I'm wondering why this is and if you can make up for it with sparge volume.  More specifically, I'm thinking that the thinner mash will make it easer for dissolved sugars to get into the solution as well as flow out of the Mash Tun?

I'm also thinking that raising the mash temp to mash out temps as well as good volumes of sparge water (for batch spargers) will accomplish the same thing?

Personally, as of late, I've been fairly happy with my efficiency.  So, if this is the case, do I even care if my ratio is 1.25, 1.5 or 2.0 qts/lb?  In other words, aside from potentially raising the efficiency are there any other benefits (negatives) to raising (lowering) your mash ratio? 
 
Thinner mash thickness leaves you with less water for Sparging which is the only downside. To compensate you would need to boil for more than an hour and no mash out, unless you decoct the Mash Out which has it's own benefits.
Cheer's
Preston
 
I more often read of the mash water ratio affecting fermentability than efficiency, but I could see how the higher dilution with water would make the sugars flow more easily. 

From Palmer's How to Brew, some other considerations beyond efficiency:

        "The grist/water ratio is another factor influencing the performance of the mash. A thinner mash of >2 quarts of water per pound of grain dilutes the relative concentration of the enzymes, slowing the conversion, but ultimately leads to a more fermentable mash because the enzymes are not inhibited by a high concentration of sugars. A stiff mash of <1.25 quarts of water per pound is better for protein breakdown, and results in a faster overall starch conversion, but the resultant sugars are less fermentable and will result in a sweeter, maltier beer. A thicker mash is more gentle to the enzymes because of the lower heat capacity of grain compared to water. A thick mash is better for multirest mashes because the enzymes are not denatured as quickly by a rise in temperature."

 
I've never heard of efficiency being at all affected by mash thickness either before that basic brewing video (the latest on their website by the way).  I think they got this information from a conversation they had with someone else regarding attenuation (one of their podcasts)

At any rate, I'm wondering how much it really impacts efficiency and if their results are just an anomaly.  Having said that, the fermentability issue is interesting.  So I guess if I want a drier higher alcohol beer I should go thin but a maltier, more full bodied beer I should go thick?

So, now this really begs the question, does a high temp, thin mash, say around 158 or a thick low temp mash cancel each out?     
 
Wildrover said:
So I guess if I want a drier higher alcohol beer I should go thin but a maltier, more full bodied beer I should go thick?

So, now this really begs the question, does a high temp, thin mash, say around 158 or a thick low temp mash cancel each out?     
Yes, and perhaps, based on Palmer's take.  I would think, however, that keeping the water ratio consistent (at whatever fits your system well) and tinkering first with the mash temp, temperature steps, and overall duration would yield more interesting changes in the fermentability of the wort.  Total mash time is another variable to consider.  I was cutting conversion short until a friend told me to check the gravity during the mash.  When gravity stops changing, conversion is complete. 
 
Would checking for starch with iodine work as well?

Wish me luck. I'm about to head downstairs and start getting things set up to do my first AG brew tomorrow. Get ready for a bunch of "What did I do wrong?????" questions.

Mark
 
stoloma said:
Would checking for starch with iodine work as well?

Perhaps for some, but I was using iodine and never got the "black flash" people describe, but the first time I checked gravity the Brix went something like 14, 19, 21, 21 from 45 minutes to 75 minutes.  So I figured I had cut short some mashes, thinking conversion was complete.  It's another use for the refractometer I already had, which is nice. 
 
I have a related question.  When you are going to do multi-step infusion mashing. You start with a low grain/water ratio or Thick mash. This thins as you add water to change steps. In the discussion you all are having, are you referring to the dough in ratio or final mash ratio?
 
Pirate Point Brewer said:
I have a related question.  When you are going to do multi-step infusion mashing. You start with a low grain/water ratio or Thick mash. This thins as you add water to change steps. In the discussion you all are having, are you referring to the dough in ratio or final mash ratio?
Actually it is the infusion ratio in general, which could be either. BeerSmith allows you to change the ratio for each step infusion. So you can start with a dough in of .9 "Water to grain ratio" and as you add water you change the infusion ratio (like 1.7) to bring up the temps. If you don't, you would have to heat the water above the boiling point to reach the desired temp's.

Clear as mud right!

Cheers
Preston
 
stoloma said:
Would checking for starch with iodine work as well?

Wish me luck. I'm about to head downstairs and start getting things set up to do my first AG brew tomorrow. Get ready for a bunch of "What did I do wrong?????" questions.

Mark

I have had actually had some success with the iodine test, not always though but it can and does work.  You take a baseline measure at the beginning and for me its always fairly black.  After about an hour to an hour and a half when I check it again the iodine should stay the iodine color, if it changes then conversion isn't finished. 
 
UselessBrewing said:
Pirate Point Brewer said:
I have a related question.  When you are going to do multi-step infusion mashing. You start with a low grain/water ratio or Thick mash. This thins as you add water to change steps. In the discussion you all are having, are you referring to the dough in ratio or final mash ratio?
Actually it is the infusion ratio in general, which could be either. BeerSmith allows you to change the ratio for each step infusion. So you can start with a dough in of .9 "Water to grain ratio" and as you add water you change the infusion ratio (like 1.7) to bring up the temps. If you don't, you would have to heat the water above the boiling point to reach the desired temp's.

Clear as mud right!

Cheers
Preston



Thanks Preston,

I'm a "Preston" also, not too many of us around!  You aren't unclear, I'm just a little slow. John Palmer indicates that the characteristics of a your wort can be changed by the ratio of water/grain of the mash, as well as temperature.  Thick mash's leave the wort less fermentable but with more "Malt" characteristics. A thinner mash will make a more fermentable wort.  Similar to lower vs higher mash temp.  His general recomendation is a water/grain ratio of 1.5 qts/lb @ 155 F, holding the temp within +- 2 F.  So my question was that if I aim for these targets, do I dough in with say 1.0 qt/lb so that water, either hot or cold, can be added to control temp, or do I dough in at 1.5 qt/lb and do what ever I must later in the mash to hold temp?
 
Pirate Point Brewer said:
.......So my question was that if I aim for these targets, do I dough in with say 1.0 qt/lb so that water, either hot or cold, can be added to control temp, or do I dough in at 1.5 qt/lb and do what ever I must later in the mash to hold temp?

If you're doing a single infusion (i.e., one mixing of water to grains) then BeerSmith calculates the water temp needed with that single infusion to "hit the mash temp" target you seek.  So, if assuming 14# of grain, a mash temp of 155F, with a ratio of 1.5 quarts of water per pound of grain, BSmith will say, for example, to use 21 quarts of water at 165F.  Once the mash is fully mixed, you should be fairly close to 155F.  One Caveat:  this is where your equipment matters because we all have different hardware.  BSmith's calculations are much better after you enter your measurements into your customized "equipment profile" that best describes your equipment.  Without that, BSmith is making a best guess from whatever "generic" equipment profile you selected. 

If you're doing a mult-step temperature mash, BSmith will suggest a lower ratio and temp for the first infusion, and then higher temps for the second infusion to boost the overall blended temps.  Every scenario will differ, depending on your mash profile you seek. 

One last caution:  starch conversion starts immediately as does enzyme "death" if your mash temps are too hot.  Have some ice cubes ready to quickly cool things down in case you overshoot the mash temps.  As you "dial in" your equipment into BSmith, this risk decreases to near zero and you'll be hitting your targets reliably. 

Hope that helps. 
 
+1 MaltLicker
Many variables, same outcome (((BEER)))  ;D

So is Preston your first, middle, or last name? It's my first name.

Cheers
Preston
 
UselessBrewing said:
+1 MaltLicker
Many variables, same outcome (((BEER)))  ;D

So is Preston your first, middle, or last name?

Cheers
Preston


Preston is my first name. Thanks for asking!
I'm also a Texan by birth but we now live in Southeast Michigan. 

Your reply is great. I have been attempting to do something similar. Because I was unsure of myself and did not wish to end up heavy on water and have to boil it down to batch size, I made a single infusion with a strike temp of 165 F looking for a mash temp of 155 F. I was afraid to go higher in strike water temp for fear of shocking/killing a portion of the grain. This has usually left the mash a little low in temp so rather than thin the mash by adding more water, I would do small decots, about 2 qts at a time, to bring the temp up. Since making a mash/lauter tun (48 qt chest & bazooka screen) I have made 3 batches as described above. Efficiencies rang from 63% to 68%. The discussion does leave a couple of more questions. I hope you don't mind;

* What is max safe temp of infusion water that will not kill enzymes?
* What is max safe mash time in the 145 to 155 F range to not extract tannins?
New but closely related topic
* In a single Batch sparge, is there a good ration between mash/sparge volume to use when targeting a desired boil kettle volume yet still extract the most sugar?

Thanks & all the best of the season in Texas - I'm too old to be this cold in Michigan!
Preston
 
Pirate Point Brewer said:
The discussion does leave a couple of more questions. I hope you don't mind;
Not at all.
* What is max safe temp of infusion water that will not kill enzymes?
That depends on the Mash Profile you are using, and the amount of water in the MT already. Different enzymes die off at different temperatures. Use the Strike/Infusion Temp calculator in BeerSmith, IT WORKS! As a Reference, there are some really good books that cover this in great detail. How to Brew (www.howtobrew.com) by John Palmer is one of them.
* What is max safe mash time in the 145 to 155 F range to not extract tannins?
If you stay in that range for 45 min to an hour, you should not get any tannins (also known as Polyphenols). I'm not so sure that time is a factor. Take a tripple Decoction for instance, This process can leave the grains on water for as long as 8 hours. If it was an issue, I would think it would raise its ugly head during that process! RIGHT? Usually the tannins come from over sparging and to much heat. Hops can also bring out a Tannin flavor. I have read that 2/3 of tannins come from the process, and 1/3 from the hops.
New but closely related topic
* In a single Batch sparge, is there a good ration between mash/sparge volume to use when targeting a desired boil kettle volume yet still extract the most sugar?
Most people use 1.25 qt/lb which is the default in BeerSmith. But you this is flexible and you can adjust as needed. If you are making a really big beer that has 20# of malt in it for 5g batch. You may find that 1.25 is to much, and you wont have any water left for the sparge, so you adjust as needed.

So what it comes down to, is this. I have no Hard Fast answers, Experiment and Learn, but most of all BREW!

Hope this helps
Cheers
Preston
 
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