Mash Question

[Jerkey]

I was watching a brew TV video about all grain brewing. In the video the guy mashed for the standard hour and then he added near boiling water to the mash to raise the temp to 170 and then stirred the grain up and closed the lid and let it set for 10 minutes then he did the vorlof and fly sparged as usual. Is this method unusual.

https://youtu.be/AcRXjdlcvKY

 

[pharaohpierre]

Well to me that is somewhat unusual if he added the 170F water to the mash without transferring the wort to the kettle first. I'm assuming that he did transfer the wort and now he is sparging to get the second runnings. The reason for the 170 water is because the enzymes (in 1 hour) have converted the starch to sugars in the original mash and now this temperature will help denature the enzymes and prevent any unwanted enzyme activity. This is normal and highly advised to make sure you collect all that sugar from the mash.

I hope I answered that correctly given that I have not seen the video

 

[Natdavis777]

I was watching a brew TV video about all grain brewing. In the video the guy mashed for the standard hour and then he added near boiling water to the mash to raise the temp to 170 and then stirred the grain up and closed the lid and let it set for 10 minutes then he did the vorlof and fly sparged as usual. Is this method unusual.

This is called a "Mash Out". By raising the mash temp, you denature the enzymes and "lock in" your mash profile. This is very common among brewers. The reason they used near boiling water vs say 170F water, is that it take a smaller amount of boiling water to raise the temp of the entire mash volume (thus saving more sparge water volume).

After the mash temp is raised, you can vorlouf/sparge as usual. This process doesnt have to be done, but enzymatic activity can still take place during the sparge if the mash stays within the given enzymatic temp ranges.

 

[SpeedYellow]

A mash out at 170 is fine, but isn't necessary. If you have a specific reason to want to stop the enzymes from continuing to convert, then go ahead and do it. I feel that that water is better used as sparge water personally.

 

[Jerkey]

https://youtu.be/AcRXjdlcvKY

 

[tsl346]

I use this process every brew. I like to get to 170 for mash out because at the higher temperature the sugars will dissolve more into the water and you will get higher efficiency and I have seen it be more consistent. With this method and a 40-50 minute fly sparge I consistently get 78-82% efficiency. I use boiling water because

1) You can easily measure the amount of boiling water needed to raise your mash to 170
2) You use as little water as possible to get to that temp, leaving more water for sparging

 

[SpeedYellow]

I use this process every brew. I like to get to 170 for mash out because at the higher temperature the sugars will dissolve more into the water and you will get higher efficiency and I have seen it be more consistent. With this method and a 40-50 minute fly sparge I consistently get 78-82% efficiency. I use boiling water because



1) You can easily measure the amount of boiling water needed to raise your mash to 170

2) You use as little water as possible to get to that temp, leaving more water for sparging

Can you cite to anything that shows that adding water for a mash-out results in greater efficiency? Seems to me that instead of tossing in, say, 1.5 gal of water for the mash-out, you could have better used that water later as sparge water. So you'd get better efficiency by NOT mashing out since you'll have more water to sparge with. (Of course, if you direct heat, this isn't applicable).

 

[Natdavis777]

I pretty sure there is something cited on this site about solubility of sugar in different temps, and there is no difference in solubility in lower mash temps vs mash out temps. I want to say Gavin_C posted about it.

Either way, I average 78-82% whether I mash out or not. I base my increased efficiency on proper pH, minimized dough balls, and an appropriate fly sparge speed.

 

[Natdavis777]

Nevermind, it was @doug293cz here in this thread.

 

[Jim311]

As a pretty new brewer I can't help but think people put way too much energy into sparging efforts and maximum efficiency when in reality your efficiency has little to do with overall flavor (within reason).

 

[day_trippr]

otoh, for folks that have been brewing for a decade or more, trying to hit theoretically sound numbers can make the mundane more interesting.

And that mash-out thing has been SOP for fly-sparging for like forever...

Cheers!

 

[tsl346]

Can you cite to anything that shows that adding water for a mash-out results in greater efficiency? Seems to me that instead of tossing in, say, 1.5 gal of water for the mash-out, you could have better used that water later as sparge water. So you'd get better efficiency by NOT mashing out since you'll have more water to sparge with. (Of course, if you direct heat, this isn't applicable).

No direct heating, using an igloo cooler mash tun. And no citation, just what I have experienced. Call it pseudo science but going to this method jumped my efficiency up about 10% instead of fly sparging with the full volume of water. It has also been more consistent.


NatDavis

As for the Kai experiment this seems like a different test because he did get to a mashout temp on each, which is the time where there will be the most sugar able to be dissolved. Also, no hard data to back this up, but just because the water itself can hold all of the sugar in the mash, it does not mean that the rate at which the water takes that sugar into solution is the same.

 

[doug293cz]

As for the Kai experiment this seems like a different test because he did get to a mashout temp on each, which is the time where there will be the most sugar able to be dissolved. Also, no hard data to back this up, but just because the water itself can hold all of the sugar in the mash, it does not mean that the rate at which the water takes that sugar into solution is the same.

There is no "rate at which the water takes that sugar into solution" because the sugar is in solution when it is created from the starch. The reaction takes place in solution in the water. There is never any solid sugar to dissolve. So, the fact that sugar dissolves faster in hotter water doesn't matter because the sugar starts out dissolved.

The fact that sugar solubility is higher at higher temperatures plays no role because the sugar concentration in wort is well below the saturation level, even at room temperature. Room temperature wort is saturated at about 44 weight % (SG of about 1.200), and at mash temps saturation is 66.7% (SG of about 1.330.) You don't need hotter water to keep the sugar in solution.

Brew on

 

[tsl346]

There is no "rate at which the water takes that sugar into solution" because the sugar is in solution when it is created from the starch. The reaction takes place in solution in the water. There is never any solid sugar to dissolve. So, the fact that sugar dissolves faster in hotter water doesn't matter because the sugar starts out dissolved.

The fact that sugar solubility is higher at higher temperatures plays no role because the sugar concentration in wort is well below the saturation level, even at room temperature. Room temperature wort is saturated at about 44 weight % (SG of about 1.200), and at mash temps saturation is 66.7% (SG of about 1.330.) You don't need hotter water to keep the sugar in solution.

Brew on

Good points and it makes sense that it is all already in solution but I'm not sure I'm following all of what you're saying. Can you help me understand what sparging is actually doing then? If all that sugar is already dissolved into the water, then it seems that just draining out the wort from the mash tun should give you all the sugars that can be removed from the mash. Are you just replacing some of the water with sugar dissolved in the grains with fresh water?

 

[SpeedYellow]

If all that sugar is already dissolved into the water, then it seems that just draining out the wort from the mash tun should give you all the sugars that can be removed from the mash.

Remember that after you drain the mash tun, you leave behind lots of your sugary wort, namely 1.3 gallons for every 10 lbs of grain. So you're grabbing most of that sugar when you add your batch sparge water.

 

[doug293cz]

Remember that after you drain the mash tun, you leave behind lots of your sugary wort, namely 1.3 gallons for every 10 lbs of grain. So you're grabbing most of that sugar when you add your batch sparge water.

Actually, you leave more than 1.3 gal of wort behind if your apparent absorption is 0.13 gal/lb. Let's say you mashed 10 lbs of grain having 80% extract potential (dry basis) with 6.8 gal of water, and you recovered 5.5 gal of wort (no sparge process). Your apparent grain absorption is (6.8 gal - 5.5 gal) / 10 lbs = 0.13 gal/lb. However, that wort is at 11.9˚Plato, which is 11.9% sugar and has an SG of 1.048. The wort contains 5.74 lb of sugar and 5.08 gal (42.3 lb) of water, so you actually left 6.8 - 5.08 = 1.72 gal of your strike water in the spent grain. More importantly, you also left 1.95 lb of sugar in the spent grain (dissolved in the 1.72 gal of retained water). Total wort retained in the spent grain is 1.87 gal. So, the true retained water is 0.172 gal/lb and true retained wort is .187 gal/lb.

We normally only deal with the apparent grain absorption rate, as that is what we need to do our batch calculations (Total brewing water = Volume to BK + apparent grain absorption rate * lbs of grain)

Brew on

 

[doug293cz]

Good points and it makes sense that it is all already in solution but I'm not sure I'm following all of what you're saying. Can you help me understand what sparging is actually doing then? If all that sugar is already dissolved into the water, then it seems that just draining out the wort from the mash tun should give you all the sugars that can be removed from the mash. Are you just replacing some of the water with sugar dissolved in the grains with fresh water?

Taking my previous response further, we can calculate the difference between no sparge and batch sparge:

                     No-Sparge   1 Sparge
                     ---------- ----------   
Grain Weight          10 lb      10 lb
Strike Volume         6.8 gal    4.05 gal		
1st Run-Off Volume    5.5 gal    2.75 gal
1st Run-Off Sugar     5.74 lb	 4.57 lb
Mash Retained Sugar   1.95 lb    3.11 lb
Sparge Volume         0          2.75 gal
2nd Run-Off Volume    0          2.75 gal
2nd Run-Off Sugar     0          1.85 lb
Mash Retained Sugar   1.95 lb    1.26 lb

Total BK Sugar        5.74 lb    6.43 lb
Lauter Efficiency     74.6%      83.6%

So when you sparge you leave more sugar in the grain on initial run-off, but you get that back and more when you add the sparge water to rinse more of the sugar from the grain.

Brew on

 

[SpeedYellow]

Taking my previous response further, we can calculate the difference between no sparge and batch sparge:

[:

Thanks for the detailed write up! I never thought about it at this level of detail, but it makes sense. Very cool!

 

[tsl346]

Taking my previous response further, we can calculate the difference between no sparge and batch sparge:

Brew on

Great info, thanks!

I have always heard it said as "rinse" the grains but from what you described that's not necessarily what's happening since the sugar is not really in the grains to be "rinsed", right? After you have drained your first runnings, you now have grains + water with a certain amount of dissolved sugars in it. Then you're adding fresh water and all of the sugar is dispersing into the total amount of water and equilibrating. Then you are draining it leaving the same amount of water as before with less sugar. Is this a reasonable way of thinking about it? And of course with fly sparging it's basically the same thing except with a gradient through the mash tun, not fully equilibrated.

If this is right then I do think I understanding the sparging process better overall but it doesn't necessarily answer what I was originally thinking. If you're fly sparging I would think that the rate of equilibrium of the sugars into the rest of the water would matter and then wouldn't the temperature of the mash out effect this?

 

[tsl346]

Time for my own experiments!

And more BEER!!!

 

[slym2none]

So... a mash-out at 170 happens pretty quickly, and that's why there is no tannin extraction?

I have always heard of mashing out at 170, but to never let the water & grains get above 160 because of astringency due to tannin extraction.

 

[SpeedYellow]

So... a mash-out at 170 happens pretty quickly, and that's why there is no tannin extraction?

I have always heard of mashing out at 170, but to never let the water & grains get above 160 because of astringency due to tannin extraction.

No, the current thinking is that you get tannin extraction due to pH and temp both being high. If your pH is normal then you won't get tannin extraction even at like 180F. I'm not claiming this as truth, only what some folks are saying.

 

[slym2none]

*takes notes*

 

[doug293cz]

Great info, thanks!

I have always heard it said as "rinse" the grains but from what you described that's not necessarily what's happening since the sugar is not really in the grains to be "rinsed", right? After you have drained your first runnings, you now have grains + water with a certain amount of dissolved sugars in it. Then you're adding fresh water and all of the sugar is dispersing into the total amount of water and equilibrating. Then you are draining it leaving the same amount of water as before with less sugar. Is this a reasonable way of thinking about it? And of course with fly sparging it's basically the same thing except with a gradient through the mash tun, not fully equilibrated.

That's pretty much it. Although it's really the retained wort volumes that are equal on the two runnings, and the water volumes are slightly different.

If this is right then I do think I understanding the sparging process better overall but it doesn't necessarily answer what I was originally thinking. If you're fly sparging I would think that the rate of equilibrium of the sugars into the rest of the water would matter and then wouldn't the temperature of the mash out effect this?

Yes, temperature is important for fly sparging for the reason you state. Fly sparging is a dynamic (non-equilibrium) process. You want all of the sparge water to get as close as possible to the equilibrium sugar concentration at each level of the grain bed as it passes by. If the water passes thru too quickly, or is too cold, then it doesn't come as close to equilibrium at each vertical level, so more sugar is left behind.

Brew on

 

[doug293cz]

No, the current thinking is that you get tannin extraction due to pH and temp both being high. If your pH is normal then you won't get tannin extraction even at like 180F. I'm not claiming this as truth, only what some folks are saying.

Yes, the pH has to be above about 6 in order to have significant tannin extraction. If this weren't the case, then all decoction mashed beer would have high tannin levels, since a portion of the mash is actually boiled.

Brew on

 

[slym2none]

Thanks for continuing my education!!!