Herms Temps

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sama

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with these herms setups,i notice theres a temp varaition from actual mash to hx output(where most probes seem to be). Does that meen your not actually getting a sugar profile of say a 67c mash.?? like,if you soak a cup of grain in water,and that mash is at 65c ,if you collect just wort,heat it to 67c,does the profile change? or does the actual cracked grain need to be infused at 67c to obtain a "medium body profile" for instance?? do you get what i meen lol?? sort of like is the worts prfile changing when i mash out or am i just stopping the grain from any further conversion.. like,.so confusing,like (spoken like a 15 year old girl)
 

Crusty

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with these herms setups,i notice theres a temp varaition from actual mash to hx output(where most probes seem to be). Does that meen your not actually getting a sugar profile of say a 67c mash.?? like,if you soak a cup of grain in water,and that mash is at 65c ,if you collect just wort,heat it to 67c,does the profile change? or does the actual cracked grain need to be infused at 67c to obtain a "medium body profile" for instance?? do you get what i meen lol?? sort of like is the worts prfile changing when i mash out or am i just stopping the grain from any further conversion.. like,.so confusing,like (spoken like a 15 year old girl)
It's a really good question & it's been discussed here before somewhere. When doing a single infusion in an esky mash tun or an urn like myself, my mash temp is the actual temperature that I will be resting at. A herms or rims will be a bit different. The actual hex temperature will be at your set point but the temperature of the mash will lag behind somewhat. How long it takes to catch up will be variable from one system to another. How important that is is debatable but if aiming for a sacc rest off 66deg at hex exit, what actual temp is the mash. Considering conversion happens in the first 15-30mins or so, you may not be getting what you are aiming for.
 

Helles

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Dont know what your talking about but
My HERMS coil is in the HLT @ 75'c
Dont know what temp wort comes out But
It works perfectly 80% eff
Low final gravity @ low mash temp 63'c (Light body etc)
So if you pump quick enough enzymes are not denatured and still convert

Not sure if this is what your talking about as post made no sense ( well i dont think it did)
 

Helles

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It's a really good question & it's been discussed here before somewhere. When doing a single infusion in an esky mash tun or an urn like myself, my mash temp is the actual temperature that I will be resting at. A herms or rims will be a bit different. The actual hex temperature will be at your set point but the temperature of the mash will lag behind somewhat. How long it takes to catch up will be variable from one system to another. How important that is is debatable but if aiming for a sacc rest off 66deg at hex exit, what actual temp is the mash. Considering conversion happens in the first 15-30mins or so, you may not be getting what you are aiming for. This is another reason I sold my rims system & went to BIAB in the urn. My sacc rest is my mash temp that I am aiming for.

The ACTUAL mash temp is what the ACTUAL mash temp is
The only thing i consider is how long the wort is in the HERMS /RIMS
Will this time denature the enzymes
And adjust mash temp and Water/grain ratio to match what you want ( i use FG to do this)
 

Adam Howard

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Once you crack the grain and mix it with water the contents of the grain becomes soluble and the grain bed is essentially just a load of husk. Heating the liquid in the mash to the desired mash temp is all you need as both the enzymes and the starches to convert are in the liquid and not in the grain bed.
 

sama

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Yeh Adam and crusty got what I was getting at. consider a single infusion mash at 65.if you drain that wort off,and heated it to 67 would it alter the sugar profile,ie would it now have a profile akin to a mash that was original infused for 67c?
 

Thirsty Boy

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Wort temp is the important one - your mash will always lag behind your heat-ex temp a little, although if you have an efficiency flow set-up, not for long and not by much. But that's only for Ramps - if you are doing a single infusion at X degrees, then there is (or should be) no difference between the mash temp and the ex heat-ex temp.

Think about it this way - when you start ramping you have the original mash temp... thats the temp of the liquid coming out of the bottom of the mash tun, then you have the temp of the liquid going in the top which will be higher and you have the "mash temp" which presumably you measure in the middle somewhere that you can sort of consider an average. As the heat ex adds heat to the system, all the temps will approach your target temp, the heat-ex temp will get there first, followed by the mash temp and eventually even the wort exiting the MT - then the heat ex will stop adding "ramp" heat and just go into maintaining temps by adding back any losses that occur.

The way I handle it, is to consider the mash in two parts. There are ramps and rests. Rests are when the system has become stable, ramps are getting there. When I'm planning a mash schedule, I look at how long the ramp will take and the temp differential, and I think of it as a pseudo rest at its average temperature. My system ramps to a stability at around 1 per minute, so a typical mash for me might be....

Mash in at 55 rest for 5 mins - ramp to 65 over 10mins - rest at 65 for 60min - ramp to 78 over 12mins - sparge

And that equates mentally to a series of rests with "instant" temperature changes of

mash in at 55 and rest for 5mins - rest at 60 for 10mins - rest at 65 for 60mins - rest at 71 for 12mins - sparge

If you dont account for ramp times, then I find things tend to end up a little more fermentable than I was planning.
 

Crusty

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Wort temp is the important one - your mash will always lag behind your heat-ex temp a little, although if you have an efficiency flow set-up, not for long and not by much. But that's only for Ramps - if you are doing a single infusion at X degrees, then there is (or should be) no difference between the mash temp and the ex heat-ex temp.

Think about it this way - when you start ramping you have the original mash temp... thats the temp of the liquid coming out of the bottom of the mash tun, then you have the temp of the liquid going in the top which will be higher and you have the "mash temp" which presumably you measure in the middle somewhere that you can sort of consider an average. As the heat ex adds heat to the system, all the temps will approach your target temp, the heat-ex temp will get there first, followed by the mash temp and eventually even the wort exiting the MT - then the heat ex will stop adding "ramp" heat and just go into maintaining temps by adding back any losses that occur.

The way I handle it, is to consider the mash in two parts. There are ramps and rests. Rests are when the system has become stable, ramps are getting there. When I'm planning a mash schedule, I look at how long the ramp will take and the temp differential, and I think of it as a pseudo rest at its average temperature. My system ramps to a stability at around 1 per minute, so a typical mash for me might be....

Mash in at 55 rest for 5 mins - ramp to 65 over 10mins - rest at 65 for 60min - ramp to 78 over 12mins - sparge

And that equates mentally to a series of rests with "instant" temperature changes of

mash in at 55 and rest for 5mins - rest at 60 for 10mins - rest at 65 for 60mins - rest at 71 for 12mins - sparge

If you dont account for ramp times, then I find things tend to end up a little more fermentable than I was planning.
Top post TB.
This is kinda what I was getting at. Ramping from protein rests or from sacc rest to mash out there is certainly a lag in the mash temp compared to the hex exit. I'm unsure how far or how long the lag is or was, I can't remember but on a couple of occasions, my PID was reading 60deg when ramping from protein rest to sacc rest but the mash temp was quite different. I stuck a thermo in the grain bed & could see what I expected, the top of the grain bed was hotter than the middle of the mash & I assume the bottom of the mash where the wort exits would be different again. So the mash temp I assume was an average of all of these. I often thought about the PID sitting nicely at 66deg & wondered how long before the grain bed caught up to the actual target mash temp. I guess it doesn't matter too much as the beers were on par with what I was aiming for anyway.
 

hsb

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It doesn't matter what temperature the grain bed is, it's the liquid being recirculated through it that's extracting the sugars, is my take on HERMS. Ignore the grain bed and focus on good recirculation and monitoring HEX exit temp?
And be consistent from brew to brew is most important of all, that way if there is a 'problem', you can address it.

I follow manticle's excellent collated advice on rest temps and almost always do a protein rest, a short low rest 63C, longer high rest 68C, then mashout - exact times/temps vary by style, but I feel I get a more balanced profile than a straight 66C mash. YMMV. IMHO. etc..
 

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