Mash water volume

[Hiphop]

Hey I have been all grain brewing for about 1-2 years now and just had a quick question about mash water volume. Is there a certain reason to go with 1quart of water per pound of grain vs 1.5quarts of water per pound of grain? I usually do 1quart/pound because of limited space in mash tun when doing 10-12 gallon brews. I normally don’t have issues with mash temp and don’t really taste a difference. I didn’t know if there was a scientific reason why you would go with a certain volume per pound

Thank you so much for the advice

 

[RPh_Guy]

I ignore mash thickness entirely. It really doesn't matter.

Half of the water is used for the mash and half for the batch sparge.

 

[BrewingAroundtheRrealm]

When I had a smaller 5 gallon cooler for a mash tun I routinely used 1 qt./pound. When I upgraded to a 10 gallon mash tun I changed to 1.25 qt./pound. The only difference is in the amount of sparge water required. 2 sparges in the 5 gallon. 1 sparge in the 10 gallon. I think the main advantage of using 1.25 is that I'm saving time. I only have 1 sparge to deal with.

I haven't detected a difference in flavor or profile.

 

[JimRausch]

Shouldn't be a difference in flavor profile, but I have found with my system that a thicker mash = a lower yield. In my 5G drink cooler-with-a-braid system, I generally mash in with about 4G and sparge with the same, but the mash thickness varies depending on what my grain bill is. Above 13 lb. of grain, I go to my larger cooler system.

 

[Hiphop]

Shouldn't be a difference in flavor profile, but I have found with my system that a thicker mash = a lower yield. In my 5G drink cooler-with-a-braid system, I generally mash in with about 4G and sparge with the same, but the mash thickness varies depending on what my grain bill is. Above 13 lb. of grain, I go to my larger cooler system.

I have both a 5 gallon and a 10 ten gallon Home Depot round cooler. I usually use the ten gallon cooler for all the mashes. (I found less of a chance of a stuck sparge) I usually end up going with a 1.5quart per pound of grain which end up around 3.8-4 gallons of mash water. I usually round up to 4 gallons to account for water loss of the grains soaking up water. When you say you have less yield, what do you mean? Do you mean less sugar or less wort?

 

[RM-MN]

I didn’t know if there was a scientific reason why you would go with a certain volume per pound

There sure is a scientific reason to mash with that certain volume. In fact there are 2. One is that my mash tun is too small and I need to use less water so it plus the grain fit the mash tun. The other is for efficiency. Mashing a little thicker allows you to do a double batch sparge which should get you higher efficiency than a single batch sparge. In practice this may not work out because the thicker mash gets you lower efficiency and the double sparge may not overcome that.

 

[oakbarn]

I have always used the 1.25 but sometimes add a little if I think too thick. I have made wet Mashes and they flow very easy compared to a thick one. Maybe one of the "Brew Myths" like not oxygenating the hot wort.

 

[JimRausch]

When you say you have less yield, what do you mean?

Sorry, should have said lower mash efficiency.
At 1.4qt/lb I might get my average of 75%, but with a thicker mash, say 1.0qt/lb my ME will be around 65%. I've read an explanation somewhere in the past, but can't currently find the source- too many Books!! I believe it has something to do with enzyme concentrations vs. substrate. There's a graph out there somewhere........

 

[BeerMaverick]

Germans tend to mash thinner (~2 qt/lb or higher) since they pump their mash between vessels (needs to be fluid enough) and in England they tend to mash thicker (~1 qt/lb) - this was from a BeerSmith podcast. As noted above though, I do thicker mashes in order to fit more grain in the MLT for bigger beers, but the thicker you go the lower the mash efficiency since it's tougher for water to completely surround and "wet" all the material for conversion.

 

[cactusgarrett]

Not final product related, but one issue, with my setup (larger cooler MLT) is that with less water (lower ratio) I have a harder time maintaining mash temp due to smaller thermal mass. I typically like sparging with more water, when possible, but with smaller beers I mash thinner more often than not in order to hold my sacc rest temps.

 

[RM-MN]

Not final product related, but one issue, with my setup (larger cooler MLT) is that with less water (lower ratio) I have a harder time maintaining mash temp due to smaller thermal mass. I typically like sparging with more water, when possible, but with smaller beers I mash thinner more often than not in order to hold my sacc rest temps.

Two things to think about:

1. How long is your mash period compared to how long it takes to get full conversion? Have you ever taken samples during the mash to determine when you have full converion?

2. Thinner mashes have higher efficiencies. Whether this offsets the lessened amount for sparging is the question. Any ideas on that?

 

[cactusgarrett]

1. I haven't measured in ages, but I typically found conversion (with "standard" grists) in 20min. I don't mash anything shorter than 45min (for step mashes), or 60min for single infusions.

2. I should have clarified: i batch sparge, so i find the improved efficiency i get via thin mashing is more or less negated by the hit i take sparging with less water.

 

[RM-MN]

less water (lower ratio) I have a harder time maintaining mash temp due to smaller thermal mass

but I typically found conversion (with "standard" grists) in 20min

I don't mash anything shorter than 45min (for step mashes), or 60min for single infusions.

2. I should have clarified: i batch sparge, so i find the improved efficiency i get via thin mashing is more or less negated by the hit i take sparging with less water.

The second quoted part answers the first. If conversion is done in 20 miutes, the loss of temperature in a 60 minute mash is of no consequence. Only the temperature loss in the first 20 minutes matters. After conversion is done the mash is only extracting color and flavors and that can happen at a much lower temperature.

I wondered if the improved efficiency of the thin mash would be offset by the lesser amount of sparge water. You seem to have answered that. Thanks.

 

[RPh_Guy]

After conversion is done the mash is only extracting color and flavors and that can happen at a much lower temperature.

Are you sure about that?

I've seen a lot of experiments that suggest mash duration affects fermentability (the sugar composition), which indicates that the enzymes are continuing to work beyond the very short timeframe it takes to get a negative iodine test.

Also if that's true, there's absolutely no point to step mashes or mash out?

 

[RM-MN]

Are you sure about that?

I've seen a lot of experiments that suggest mash duration affects fermentability (the sugar composition), which indicates that the enzymes are continuing to work beyond the very short timeframe it takes to get a negative iodine test.

Also if that's true, there's absolutely no point to step mashes or mash out?

You're asking a complicated question. When the iodine test is negative there is no starch where the iodine can reach. It may be that the starch is so far inside the grain particles that the iodine doesn't react to it in the time we expect for the test but given more time it may and that starch then could be converted if given enough time for the water to reach it. With very finely milled grains that I use, the starch gelatinizes nearly instantly, the enzymes get activated, starch is converted, and .....there is no more starch for the enzymes to work on. At mash temperatures the enzymes are quickly denatured and that stops all conversion.

With my testing, I get negative iodine results very quickly, the gravity no longer goes up, and the wort ferments to the expected FG. Longer mashes don't seem to have any effect on this.

If your grains are not milled as fine, such as what is needed for a conventional mash tun, the starches gelatinize slower which allows the brewer more control over the fermentability. Step mashes do different things than a single infusion, and mash efficiency is lower because not all the starches are converted. Mash outs (fly sparge only) stop further conversion during the long sparge.

There are other reasons for a step mash too. Protein rests are useful for some grains and recipes. Those are step mashes.

 

[RPh_Guy]

It's my understanding that the enzymes continue to will cleave dextrins for about 2-3 hours at mash temp.
Therefore temperature throughout this timeframe will affect fermentability to some extent.
*** I agree the large majority of the enzyme activity happens early in the mash and so dropping a few degrees isn't really something to worry about. ***
FWIW I only measure mash temperature after dough in and about 20-30 mins later. It's very stable in my round cooler, which I pre-heat and further insulate with blankets/towels.

Kai's an expert, right? I'm certainly not.
http://braukaiser.com/wiki/index.ph...nd_efficiency_in_single_infusion_mashing#Time

Edit: oh, and since this thread is about mash thickness, also on that page:
http://braukaiser.com/wiki/index.ph...ncy_in_single_infusion_mashing#Mash_thickness
For a thin mash (1.2qt/lb) efficiency can vary slightly based on mash temp. For thicker mashes (2.4qt/lb) it doesn't, and also mash thickness doesn't affect fermentability.

 

[RM-MN]

Alpha amylase, the enzyme that breaks the dextrines, can survive longer than beta amylase at mash temperatures but my reading say that both are denatured quickly at mash temperatures although qucikly was not defined in terms of minutes or hours.

 

[Smellyglove]

Just to sum up and add to what others above have written:

After for instance 20 minutes, you get a negative iodine reading, it only means that the gelatinized and soluble starches has been converted. Iodine does not show starch positive on starches that has not come into solution.

Further, if this sample was taken at 65C, then you ramp up to 73C, you will most likely read a positive test at that temperature, because some starches are not soluble before a given temperature is reached. So there's more starches to convert at 65C, which will not convert unless you turn up the heat.

There's a lot of enzymatic activity going on after conversion is done. If you mash at 65C, tightly milled, you'll have conversion pretty quickly, but you will not get a high fermentable wort for instance, since the Beta amylases haven't had enough time to do their job, they work slower, because they work on the fruits of the Alpha Amylase.

So trying to do a Saison with a non diastaticus strain or no sugar, and mashing at 65C until conversion is complete, will not make a dry saison like a 2hr mash at that temperature would yield.

It's also possible just just hold back a percentage of the grist, and add it to the mash after a while if you're mashing for a long time, to get fresh enzymes into the mash.

 

[Hiphop]

So from all the responses I have recieved I can say that water volume

Just to sum up and add to what others above have written:

After for instance 20 minutes, you get a negative iodine reading, it only means that the gelatinized and soluble starches has been converted. Iodine does not show starch positive on starches that has not come into solution.

Further, if this sample was taken at 65C, then you ramp up to 73C, you will most likely read a positive test at that temperature, because some starches are not soluble before a given temperature is reached. So there's more starches to convert at 65C, which will not convert unless you turn up the heat.

There's a lot of enzymatic activity going on after conversion is done. If you mash at 65C, tightly milled, you'll have conversion pretty quickly, but you will not get a high fermentable wort for instance, since the Beta amylases haven't had enough time to do their job, they work slower, because they work on the fruits of the Alpha Amylase.

So trying to do a Saison with a non diastaticus strain or no sugar, and mashing at 65C until conversion is complete, will not make a dry saison like a 2hr mash at that temperature would yield.

It's also possible just just hold back a percentage of the grist, and add it to the mash after a while if you're mashing for a long time, to get fresh enzymes into the mash.

This is exactly what I needed for the importantance of mash temp and I will save your response for future reference but the question I had originally was would the volume of water to grain effect the outcome of beer. I love the science in your response and was looking for the science response like your answer but to the question of mash volume not temperature

 

[doug293cz]

... the question I had originally was would the volume of water to grain effect the outcome of beer. I love the science in your response and was looking for the science response like your answer but to the question of mash volume not temperature

The answer is: you will never be able to tell. There are so many variables in the process, that unless you could control all of them precisely, or ran hundreds of replicates to randomize the effects of the other variables, you can't know that a difference in taste between two beers with different mash thicknesses was due to the mash thickness, or some other variable that wasn't the same between the brews. Brulosophy tries to run experiments like this, and much more often than not, the tasting panel can't taste the difference between the beers. Unless a particular variable has a huge effect on the outcome of the beer, detecting any difference is next to impossible.

And, you can't go by unverified theory to decide which is better. Brewing texts stated that thick mashes would convert faster than thin mashes. Made sense since thick mashes have a higher concentration of enzymes (theory was higher enzyme concentration causes faster conversion.) However, when Kai Troester tested this theory, he found that thinner mashes actually converted faster. There was another variable that was more important than enzyme concentration that affects conversion rate.

Use a mash thickness that works for your process, and don't worry about it.

Brew on

 

[Smellyglove]

What the guy above said. Find the mash thickness that works best for you, and mash away. There are a tonnes of other factors which contribute to the final quality of the beer, figure out those first, then do what you feel you need to do to the mash thickness.