What is impact of mash with more than 1.5 quarts of water per pound of grains?

[jcueland]

Everywhere I've read you should have a water ratio of between 1.0 - 1.5 quarts per pound of grain for the mash. I recently started my mash with 1.0 quart per pound at 120 degrees and then increased it to 150 degrees by adding boiling water. My intention was to keep it at 1.5 quarts per pound but ended up having to add more water to a ratio of 2.0 quarts.

What impact will mashing with a ratio above 1.5 quarts per pound have on my beer? Everything else went normal...I was able to get a final wort of 5.5 gallons with an original gravity of 1.048 (my goal was 1.042).

 

[tjmac5071]

In my experience no impact. Not sure if you adjust your water or not but I run an occasional full volume mash and just adjust accordingly. If you do not adjust then mash pH could be a bit of a problem.

I am more and more convinced that grain and water wants to become beer and traditional rules are much more flexible than previously believed. In fact I used to mash at 1.25 and never deviated. Then slowly worked towards maxing out my mash tun before sparge to account for my smaller HLT. No Ill effects noted then moved to full volume for 5 gallon batches and only do that now for 5 gallons. I am looking to upgrade in the near future to a 20 gallon tun to eliminate sparging at all for all batches and streamline the brew day

 

[applescrap]

I use more than 1.5 qt per pound on every brew as do most biab brewers. Full volume brewing or sparge, grains move or water moves. Its personal choice/preference. Go with 60 percent total volume, and 40 percent total volume for sparging.

 

[RM-MN]

With the higher water to grain ration you get faster and possibly more complete conversion (as evidenced by your higher than expected OG) but you then have less sparge water to add to hit your preboil volume.

 

[Silver_Is_Money]

For simplicity, I always start with 5 gallons of strike water, so my lowest gravity recipes mash at a bit more than 2 qts. of water per pound of grist (>2:1). And my highest gravity recipes come in at about 1:1. And the rest of my recipes fall everywhere in-between.

 

[mongoose33]

I now BIAB but when I used a mash tun I'd typically use 4-4.25 gallons of strike water for up to 13 pounds of grain.

I'd then sparge w/ 4 gallons.

One key to this--and I think it's relevant to both BIAB as well as using a mash tun--is stirring the mash at about 15 and 30 minutes. My efficiency went up significantly when I did that versus just letting it sit.

*************

When I do BIAB for a similar amount of grain, I use 7.25 gallons of strike water. But I also have set my grain mill gap at about .020 as opposed to the .035 i used when using a mash tun.

As luck would have it, I get the same efficiencies between the two methods with those two differences--more water and finer crush with BIAB.

That's convenient from a recipe point of view as I thought I'd have to recalibrate recipes when I moved from traditional AG brewing to BIAB. But no. Made me pretty happy.

**********

Stir. Don't whip up a froth, but using a mash paddle or or similar gently stir around as well as trying to bring the mash at the bottom to the top.

 

[schematix]

I do no sparge which results in high water to grain ratios. Typically 2.5-3 qt/lb.

Works great but you do have to consider mash pH. Easy enough though.

 

[WestMichBrewer]

I stick to 1.25 qts/lb.
I use a calculator to do the math and try not to round up too much.
I use this figure only for consistency.
I know that if my grain is at room temp, I preheat my tun, and heat the water to mash temp +14 degrees, I will hit my mash temp after I mash in.

 

[Yooper]

I do no sparge which results in high water to grain ratios. Typically 2.5-3 qt/lb.

Works great but you do have to consider mash pH. Easy enough though.

That's my experience. If you have alkaline water especially, the mash pH can rise quite a bit with a higher volume of mash water.

Because I do a traditional mash/sparge, I usually go about 1.5 quarts/pound so I have enough sparge water. It's thin enough to stir easily and recirculate, but not too thin so that I limit my sparge.

If I was doing no-sparge (and I might soon), I would just ensure my mash pH was 5.3-5.5 or so.

 

[dmtaylor]

In my experience no impact. Not sure if you adjust your water or not but I run an occasional full volume mash and just adjust accordingly. If you do not adjust then mash pH could be a bit of a problem.

I am more and more convinced that grain and water wants to become beer and traditional rules are much more flexible than previously believed.

+1. No impact.

 

[Lefou]

With the higher water to grain ration you get faster and possibly more complete conversion (as evidenced by your higher than expected OG) but you then have less sparge water to add to hit your preboil volume.

Something else to add here. If you desire to do a decoction - and some do - adding a measure of water above 1.5qt/lb helps. Just account for absorption in grain and evaporation during the boil. I will sometimes use up to 2qt/lb of grain during a decoction.

 

[stz]

There are differences in mashing thick or thin. How much difference this makes to your beer is negligible and depends on other factors, but as a rule mashing thick protects the enzymes from being denatured as readily and allows for faster (less dilution of enzymes) and a more complete conversion. If your water has residual alkalinity it can also bring up the pH more than you'd like dependent upon grist composition. A thinner mash makes hitting mash temperature easier, it makes a stuck mash less likely and can make run off quicker/easier. I use 2.5 l/kg as a starting point which is basically 1 qt/lb though 2.7 l/kg is fairly common. Some here love 3:1 which I don't really see the need for, but each to their own.

 

[schematix]

I do no sparge which results in high water to grain ratios. Typically 2.5-3 qt/lb.

Works great but you do have to consider mash pH. Easy enough though.

Just to add to this a bit...

Mashing thin will effectively dilute the acidity of your grains. Sometimes this is to your benefit, sometimes not.

This is easy to handle though - just plug in your grain bill and full mash volume into any one of the water calculators out there and it'll tell you where you're at.

For my system a no sparge brew day is easier and for that a thin mash is naturally required. I get 100% conversion efficiency, great attenuation, great body and great foam. There are a lot more important things to worry about than the mash thickness.

 

[RM-MN]

There are differences in mashing thick or thin. How much difference this makes to your beer is negligible and depends on other factors, but as a rule mashing thick protects the enzymes from being denatured as readily and allows for faster (less dilution of enzymes) and a more complete conversion. If your water has residual alkalinity it can also bring up the pH more than you'd like dependent upon grist composition. A thinner mash makes hitting mash temperature easier, it makes a stuck mash less likely and can make run off quicker/easier. I use 2.5 l/kg as a starting point which is basically 1 qt/lb though 2.7 l/kg is fairly common. Some here love 3:1 which I don't really see the need for, but each to their own.

This was thought to be the case but it appears that it was in error as the dilution would have to be extreme to cause problems and the conversion rate seems to be as high or higher with a thin mash and complete conversion isn't uncommon.

Your comment on pH is spot on though. I usually have to add a bit of acid to get the pH I want with my thin mash.

 

[doug293cz]

This was thought to be the case but it appears that it was in error as the dilution would have to be extreme to cause problems and the conversion rate seems to be as high or higher with a thin mash and complete conversion isn't uncommon.

...

Yes, Kai Troester (Braukaiser) did some experimentation with this, and did indeed find that thinner mashes have a faster conversion rate. The reason for this is a little counter intuitive. Both starch and amylase enzymes are very large molecules, and in order for them to interact, specific locations on each of them have to come into contact in order for a starch molecule bond to be cleaved. At high concentrations, mobility of the molecules is reduced, and it is harder for them to align themselves the way they need to be (Kai refers to this as "substrate inhibition"), thus slowing down saccharification. Thinner mashes increase the molelcular mobility, thus increasing the saccharification rate.

Brew on

 

[mongoose33]

Yes, Kai Troester (Braukaiser) did some experimentation with this, and did indeed find that thinner mashes have a faster conversion rate. The reason for this is a little counter intuitive. Both starch and amylase enzymes are very large molecules, and in order for them to interact, specific locations on each of them have to come into contact in order for a starch molecule bond to be cleaved. At high concentrations, mobility of the molecules is reduced, and it is harder for them to align themselves the way they need to be (Kai refers to this as "substrate inhibition"), thus slowing down saccharification. Thinner mashes increase the molelcular mobility, thus increasing the saccharification rate.

Brew on

And that would explain why stirring the mash helps with conversion, wouldn't it?

 

[doug293cz]

And that would explain why stirring the mash helps with conversion, wouldn't it?

I believe that the primary mechanism for stirring speeding up conversion, is that the shear forces break up the layers of gelatinized starch on the surfaces of the grits. This gets the gelatinized starch into solution faster (your point, I believe), and then allows water better access to the un-gelatinized starch, so that it can be gelatinized sooner than it would have been without stirring. Starch cannot be acted on by the enzymes until it has been gelatinized, thus gelatinization is the primary rate controlling step in a mash.

I believe wort recirculation has a similar effect, although the shear provided by recirculation is less than that provided by stirring. But, then the continuous nature of the recirc allows more time for the shear to act. Whether stirring or recirc has more of an effect over the whole mash, I don't know, and probably depends a lot on the specifics of a particular process.

Brew on