Strike Calc Off ?

The Brew Mentor

The Brew Mentor

Well-Known Member
Lifetime Member
Established Member
Joined
Aug 19, 2012
Messages
2,784
Reaction score
4,368
Points
113
Hey Larry,
I used the software today to brew the Celebration clone. http://www.brewersfriend.com/homebrew/r ... tion-clone
It seems like the strike water calculator is off.
I had 13.25 lbs. of grain @ 70° and 16 Qts. of water. Your calc said 169.2 for the H2O for my mash temp of 155°
I added the H2O to my 48 qt. cooler and let it come down and rest at 169° and then added my 70° grains.
The result was very high. I quickly added about 1/2 gallon of 70° water and stirred down to 155°,
??? I would normally check this as it didn't seem right , but I was brewing at home and didn't have my other software on this laptop.
I don't know what happened, but it was way high and thankfully I was able to quickly correct it.
By the way, The Bitch Slap went mini BOS in a Comp with +/- 500 entries and 30+ IPA entries
:mrgreen:
 
Check out this equation and see if it makes sense:
http://www.howtobrew.com/section3/chapter16-3.html

In doing some reading, I found a couple posts where this formula has caused overshooting, or undershooting, but it seems to vary with the brewer (likely differences in their equipment and process).
http://www.homebrewtalk.com/f36/problem ... ons-58771/

In this case, I think process is worth examining. The formula assumes the mash tun is going to absorb a lot of heat. Even if you pre-heat the tun with 1 qt of boiling water, it will still suck energy out of the strike water. It sounds like you stabilized the strike water in the tun at 169F, and then added the grain - which explains the high temp. Next time, try starting with a cold tun, add the water at 169, then immediately add the grain, and see where it ends up.

Equipment is also good to look at: It could be you have a really awesome mash tun that holds heat well. In that case, keep your Mash Strike Heat Loss at zero. My tun is a cheap coleman 48qt cooler - I enter a value of +5 for Mash Strike Heat Loss and I hit my targets just fine.

My last question would be - were all the readings taken from the same thermometer? If no, make sure all the thermometers are calibrated.
 
So your calculator assumes heat losses to the tun. That makes sense as to why I was high. I always preheat my tun and figure no thermal losses for the tun.
I question having a preset number. Is there a value somewhere in the equipment where I can enter 0 as my heat loss to the tun? I may have just missed it.
I really want to use the program in my clinics as a tool and guide to follow on brew day, but I have to figure out my mistake first.
Brian
 
Off the Mash Calculator page;
These calculations assume zero heat loss. If you do not pre-heat your tun, a few degrees will be absorbed by the mash tun.
 
The Brew Mentor said:
Off the Mash Calculator page;
These calculations assume zero heat loss. If you do not pre-heat your tun, a few degrees will be absorbed by the mash tun.
Click to expand...

Good catch, that is wrong and will be updated. An FAQ will also be created.
 
Larry,

You also need to account for the slaking heat that is generated when water is added to grain. This heat also depends on the moisture content of the grain. There may have been a BYO article about this a while back since the author asked me to for feedback on his draft.

Slacking heat doesn't seem to be included in Palmer's formula. It's not mentioned in the HBT discussion.

Slaking heat is also called heat of hydration and it can be significant. I once had a particularly dry batch of Munich malt and with this malt I always overshot my temp by ~2 C. It was very noticeable. But for most malt the slacking heat should be fairly consistent.

Kai
 
We are open to adopting a more accurate equation. Anybody have references?
 
Hey Kai
Let me be the first to welcome you to the forum. I have followed you for many years and I appreciate all you have done to further the home brew community. Most of your stuff is a level beyond my understanding, and sometimes my eyes glaze over when you are explaining something, but thank you for all your contributions. I especially enjoyed your historical writings of German brewing processes. The historical aspect has always brought it home as to why we do what we do, because someone figured it out a long time ago. I am currently on a German lager kick, with southern German pilsner, dopplebocks, and marzen as my favorite, with an occasional roggenbier to spice things up.
Again, welcome and brew strong.
 
Thanks chessking.

I do try to make complex topics understandable, but sometimes it doesn't work without math and chemistry :)

On the other hand, most of what I write about can easily be hidden from the brewer through calculators like BF. But it's still useful to know how things works so one can make sense of calculator outputs.

Strike water temp is an interesting topic that I haven't thought of much so far. Mostly b/c I tend to work based on past experiences.

Kai
 
The next release will include an FAQ about this. At least it will be clearer. We also clarified the language on the page so it is less confusing - we hope. This equation works fine for me, but you have to go into it knowing it could take some adjustment.

In a future release we will investigate updating the equation. I will start a new thread in the feature request section when that kicks off.
 
Kai,
Welcome to BF Forum.
It's good to have you checking in. I too have learned a lot from your comments and videos.
It's nice to see someone as respected as you, in the brewing community, on a newer forum. I thought your involvement in the HBT and other forums would keep you pretty busy.
I typically use BeerSmith as software but I like what Larry is doing here and hope to be able to use his program as a tool in clinics that I put on in the store.
I hope he will be able to work this out.
I wonder what formula Brad Smith uses? I nail my temp every time with his calculations.
He probably wouldn't be interested in sharing with Larry! :shock:
Thanks Again
Brian
 
The Brew Mentor said:
I thought your involvement in the HBT and other forums would keep you pretty busy.
Click to expand...

I like to branch out and HBT got too big for me a long time ago. I’m looking into the science forum once in a while. In general I’m looking for interesting topics these days as opposed to jumping on every question I could answer. I also like to stick to my blog and wiki for copyright control.

I typically use BeerSmith as software but I like what Larry is doing here and hope to be able to use his program as a tool in clinics that I put on in the store.
Click to expand...

I haven’t used BeerSmith, or any other recipe software for a long time.

I wonder what formula Brad Smith uses? I nail my temp every time with his calculations.
He probably wouldn't be interested in sharing with Larry! :shock:
Click to expand...

I don’t think there is much original research done by the BeerSmith team. He likely uses a formula that accounts for aforementioned slaking heat and they have been published. It’s just a matter of digging through the research and publications to come up with a formula that works.

Cheers,
Kai
 
The next release will include an upgrade that will let you infuse a colder temperature of water to bring down temps if you over shoot. We are also going to beef up the FAQ on this section as well.

Longer term we can look into replacing this equation with something more robust. However the feedback Kai is giving us is keeping us plenty occupied at the moment. We will be rolling out some neat improvements in the near future!
 
LarryBrewer said:
The next release will include an upgrade that will let you infuse a colder temperature of water to bring down temps if you over shoot. We are also going to beef up the FAQ on this section as well.
Click to expand...

It would be nice if you could include an option to add ice. Ice is very efficient in lowering temps due to the heat absorbed by melting. That would be a nice tweak on this feature.

Kai
 
Interesting idea, I set it up so it protects you from adding water a -10 degrees (since that is not possible), and it warns you about that and tells you to increase the infusion amount, or raise the target temperature.

I will add this idea to the TODO list when we update the equation for this section.

Ice cubes would take some prep - you want them to be from a quality water source, and they have to be prepared the night before brew day. Would you be adding them by weight? That would get even more input intensive on the screen. Plus there is the volume expansion issue when water freezes.
 
LarryBrewer said:
Ice cubes would take some prep - you want them to be from a quality water source, and they have to be prepared the night before brew day. Would you be adding them by weight? That would get even more input intensive on the screen. Plus there is the volume expansion issue when water freezes.
Click to expand...

I just take them out of the freezer. Since I have R/O water hooked up to the fridge I don't see a problem. with that. Most should have a carbon filter for their ice from the fridge. Without it there might be a slight chlorine/chloramine concern.

I would want to add them by weight. This is the easiest. I would have to look at the screen to see how this best fits. Maybe a button to select water or ice. I also don't know how much the actual temp of the ice matters. I.e. 20 F vs. 30 F, for example. But if most of the cooling comes from melting, it could be safely ignored by assuming a standard freezer temp.

Kai
 
I like the ice idea, I would be concerned that new brewers would run with the idea and think they could use it as well in an extract batch.
I can't tell you how many new brewers think that they came up with the idea of using ice as their make up water.
Then, I have to go through the whole "Is your ice sanitary, Where did it come from" conversation of why not to.

I don't think you need to have an adjustment formula other than for step infusion mashes.
I think a simple statement like " After strike water is stirred in, if your temp settles +/- 2°, leave it alone. If you're off more than that, you can stir in a little boiling water or cold water until you get in your temp range." would suffice.

Your program can do a lot, but Brewers at this stage also need to be able to think and work to dial in their own systems.
JMO
Brian
 
I was just working through the calcs. for a new Brew and realized that I have a 5 quart void space in the mash tun. This is the area under the filter screen. I want to determine the proper strike water volume and temperature for 11.25 lb of grain with a ratio of 1.5 qts/lb.

Question: How do I account for the 5 qt. dead space under the filter screen? Add an extra 5 qts of strike water?
How do you mix the dead space water into the grain? Using the pump to recirculation it will cool it down.

Thanks:

Tom McLean
 
That's a tricky one. It debatable either way if the mash ratio includes that area (and ultimately that is your call).

I'd strike by 'volume' not by 'mash thickness' in the Brew -> Mash Calculator section. That way it will be clearer. Since you can't stir under the false bottom, it may take longer for the temperature of the mash to equalize.

I think you will need to do a few trials and dial it in. Always pad a little in cooler weather. I use a copper manifold, not a screen, so I don't have experience with this scenario.
 
You must log in or register to reply here.
Copyright © 2007-2024 Brewer's Friend, Inc. - Send Feedback - Terms - RSS Feed - Do Not Sell or Share My Personal Information

Back
Top