Fermenter's Favorite Cooler/Mash Tun Testing

[CRUNK]

Atta boy relax,and test, each system is different I have to use 10.5 gallons of water total to produce a 5 gallon batch after a 90 minute boil, loss to grain and kettle and mush tun, so point here is you need to learn your system's variances because I'm sure even conditions being identical every system will still have subtle differences.

I observed 10 guys in a club brew the exact same recipe, on their own systems, and they got 10 different tasting beers, be it however subtle the difference.

 

[jeffpn]

Maybe a lot of conversion happens in the first 10 minutes because the temps are ideal? Just spitballing here. I don't see what could be so magical about minutes 1-10.

Tractor Supply sells grains? Hmmm... I'll have to check that out!

 

[Mase]

Maybe a lot of conversion happens in the first 10 minutes because the temps are ideal? Just spitballing here. I don't see what could be so magical about minutes 1-10.

Tractor Supply sells grains? Hmmm... I'll have to check that out!

Yup! Cracked Corn! 50 lbs sack for $8.00. Should better replicate an all grain mash (thermal mass wise). The deer will love me this afternoon as they will have 50 lb of cracked corn to munch on.

And cracked corn converts between 145 and 150 degrees. Wondering what a person could do with corn mash... hmm

 

[Mase]

Long story short, I lost several degrees in the first 20 minutes, but then only 2 degrees every 20 minutes all the way through 90 minutes. In fairness, I ran this test in the garage at 37 degrees. I am confident that the dramatic temp drop was due to a 37 degree mash tun, and the two degree drop every 20 minutes had to have a lot to do with me opening up the mash tun for a minute to get the temp.

Although I hoped the 3 tests would yield exactly what to do, they did give me some direction and some expectations. Will update again once we put an all grain brew through it.

 

[CRUNK]

You could try a test also, warming your grains in a oven to see what affect it will have.

 

[GFHomebrew]

Long story short, I lost several degrees in the first 20 minutes, but then only 2 degrees every 20 minutes all the way through 90 minutes. In fairness, I ran this test in the garage at 37 degrees. I am confident that the dramatic temp drop was due to a 37 degree mash tun, and the two degree drop every 20 minutes had to have a lot to do with me opening up the mash tun for a minute to get the temp.

Although I hoped the 3 tests would yield exactly what to do, they did give me some direction and some expectations. Will update again once we put an all grain brew through it.

Did you pre heat your mash tun mase? I'm thinking if you were to boil the kettle and pour in some boiling water first whilst your waiting for you hot liquor tank to hit strike temp then you might save yourself that initial temperature drop? I think that seven degrees may be due to warming up the tun then it evens out and you get that steady measured decline.

Mate it's summer here in the land down under and I couldn't believe it but on the weekend I got a 1c temperature drop throughout my 60 minute mash I'm one lucky ba$&@rd.

 

[Mase]

I absolutely agree with you Trialben. Being in the garage at 37 degrees with a grain temp of around 56 degrees was a bit to cold and the mash would have to lose temp to heat up the mash tun.

I also think that opening the lid every 20 minutes to take a test temperature had a big effect as well because the mash has to lose heat every time I open in 37 degree (f) ambient air just to reheat the space.

For what it's worth, regarding the airspace between the top of the mash and the poorly insulated lid, we are thinking of placing a piece of aluminum foil over the mash so the mash doesn't have to lose as much heat by trying to heat all the air space.

I also think that the cracked corn would hold less thermal mass as after 90 minutes, there was no real hydration of the mash as you could always see the corn under a few inches of water, whereas a mash is much "thicker", if that makes sense.

As I mentioned earlier, I didn't get the answers/results I was hoping for in the testing, but it gave me guidance on how to work with the equipment to better maintain temperature throughout the Mash.

I am confident that by preheating the mash tun, having the grains at a higher ambient temperature (56 degrees in the 3rd test), wrapping the mash tun in a blanket, and the "thicker" mash from an all grain as opposed to water or cracked corn will all aid in maintaining a couple degree loss over at least a 60 minute window.

This is all part of the "learning your equipment" that is so crucial to successful home brewing.

I will update again when we do our first all grain in a couple weeks and instead of opening the mash tun for temp readings, I will use a probe digital thermometer as long as I can figure a way to get the probe into the mash tun with out leaving heating out.

 

[jeffpn]

Make sure that you consider that the mash doesn't have a consistent temperature throughout. In other words, sticking a probe in one spot so you don't have to open the lid might not give you a real indicator of the average temperature. I think it's best to stir the mash before you take a temperature reading.

 

[Mase]

Make sure that you consider that the mash doesn't have a consistent temperature throughout. In other words, sticking a probe in one spot so you don't have to open the lid might not give you a real indicator of the average temperature. I think it's best to stir the mash before you take a temperature reading.

I guess I could have expanded on that, good catch. I do mix the temperature probe like I am stirring water in the mash to get an even temperature reading. That's one of my concerns with relying on a thermometer on a pot as it may be an accurate thermometer, but it may not be reading the average temperature.

 

[GFHomebrew]

That aluminium foil on top of the mash is a goer I do this as well and wrap with an old blanket every little bit helps. I stir the mash every 20 minutes or so an then take a temperature reading then. I'm thinking of adding a thermowell into my keggle for constant temperature readings. The good thing about doubling your mash tun as your kettle is that you can directly heat your mash if it's dropped a bit and also do step mashes. There is some trial and error with this too as I've found it will continue to heat after you've killed the flame usually 1c ish.

 

[Nosybear]

That aluminium foil on top of the mash is a goer I do this as well and wrap with an old blanket every little bit helps. I stir the mash every 20 minutes or so an then take a temperature reading then. I'm thinking of adding a thermowell into my keggle for constant temperature readings. The good thing about doubling your mash tun as your kettle is that you can directly heat your mash if it's dropped a bit and also do step mashes. There is some trial and error with this too as I've found it will continue to heat after you've killed the flame usually 1c ish.

To Jeffpn's point: At homebrew scale we can't control our temperatures closely enough to even worry about a whole lot of control unless we're using some kind of recirculation setup like HERMS or RIMS - I'm not. So my mash technique: Get it close and forget about it for an hour or so. Obsessing over a degree or two at a single point in the mash when there could be a ten degree temperature differential between the center of the mass and the edges of the tun is a bit absurd to me. A degree or two difference from actual temperature given my converted cooler process probably won't make enough of a difference I or anyone else could detect. One thing I can say with great certainty: That degree or two's worth of obsession at our scale won't make that much of a difference in the outcome.

 

[Mase]

Obsessing over a degree or two at a single point in the mash when there could be a ten degree temperature differential between the center of the mass and the edges of the tun is a bit absurd to me. A degree or two difference from actual temperature given my converted cooler process probably won't make enough of a difference I or anyone else could detect. One thing I can say with great certainty: That degree or two's worth of obsession at our scale won't make that much of a difference in the outcome.

Great insight! Since we are new to brewing (2 extracts and one BIAB), and with the volumes of information available online and in books, until one starts brewing, one doesn't know how much an affect (great or little) being off on targets really means. Although there is a ton of information available for brewing techniques, very little of the information indicates how critical or what may or may not happen if you miss targets.

breathing a slight sigh of relief!

 

[jeffpn]

I bet I'd make a lot of brewers cringe if they saw how I make beer. I have 2 editions of the same book, which is my entire brewing library. No YouTube videos, no podcasts. I know just enough to make the beer that I like.

 

[Mase]

I may be stretching it a bit here with the comparison (brewers and bakers), but as a noob, If I were to make a cake from a recipe, and the temperature said 350 for 40 minutes, and then I realized that i baked that cake at 340 for 40 minutes, or if the recipe calls for a 2 cups of flour and I only put in 1 and 3/4 cups, until the cake is baked and I can taste it, I wont know if those misses were critical or not. An experienced baker doesn't use box kits, rather from scratch (all grain comparison) and already knows how much they can drift away from the recipe ingredients or time before it effects things. Seeing everyone's responses has helped me to at least understand that not being exact is not a failure.

This forum has helped me more in the past week since I joined, then 3 solid months and countless (less solid) months of research online and in a couple books and hundreds of videos.

 

[jeffpn]

Not to mention that you can go as shallow or as deep into brewing knowledge as you want, and still make good beer. You don't have to know everything. I know people that were quite happy and entertained by making a hopped extract kit served from the funny looking keg. Other people do an unhopped extract boil with their own hop additions. I did that for years. I also liked the convenience of buying a kit. I'll start a war here by saying I do all grain now, BIAB. It's fun to me, and it's what I like. All I added go my existing extract set up was a bag to hold the grains for the mash. I don't want to devote the floor space to a 3 vessel set up. I'm where I'm at, and probably as far as I'll go, since everyone views homebrewing as a progression.

 

[Mark D Pirate]

I know old guys been brewing kits for 20 years , never felt the need to go further .
The beer is not to my liking to be honest as its thin and bland and sometimes presents off flavours due to ambient brewing or slight infection or under pitching the winter brews
They agree mine is very tasty but a bit wanky ( pretentious )
Really news to make another kit lager so I can show them how a well handled and correctly brewed beer can taste !

As has been said , its your beer and your hobby so you can do almost whatever you like and you'll still end up with beer

 

[Mase]

I know old guys been brewing kits for 20 years , never felt the need to go further .
The beer is not to my liking to be honest as its thin and bland and sometimes presents off flavours

Do you think kits are much better today as the demand is higher and the kits are fresher and with better ingredients then the kits even a few years ago?

I guess I will find out if our first all grain tastes noteably better than the 3 kits that we have brewed, but I have to say that the beer we have made is delicious and far better then anything I have purchased in the same style as a commercial beer.

Hmmm... in looking at beer kit reviews I often see where the all grain kit reviews typically show less "stars" as opposed to the extract kits of the same particular recipe that typically have higher reviews/stars. Is that because the kits are predominately made/reviewed by noobs, and all grain brewers are more experienced and a better judge of the taste/body, etc., etc.?

 

[jeffpn]

You may have a point. And it might tie into what I was talking about, where some people don't desire to learn everything there is to know about brewing, and other people are hypercritical about everything.

I first start brewing Brewers Best extract kits a bit over 20 years ago. I was quite happy with them, especially their Pale Ale kit. When I resumed brewing about 3 years ago, I bought their extract kits again. They seemed as good as they were when I started brewing. I've been doing BIAB for the past 2 years or so. Ive never had any problems or complaints with their extract kits.

 

[jmcnamara]

to your point Mase, i think brewing is more like cooking rather than baking (i don't much like the rigidity of baking)

i don't like to measure ingredients when i cook, preferring to just eyeball it and adjust to taste. as long as you have even a general idea of your ingredients, it'll usually turn out just fine. maybe not the greatest, but edible / drinkable at least

 

[Mase]

to your point Mase, i think brewing is more like cooking rather than baking (i don't much like the rigidity of baking)

i don't like to measure ingredients when i cook, preferring to just eyeball it and adjust to taste. as long as you have even a general idea of your ingredients, it'll usually turn out just fine. maybe not the greatest, but edible / drinkable at least

I actually should have used a cooking analogy rather than baking as I remember my wife telling me not to long ago that cooking allows for a good bit of flexibility where baking does not.

Thinking about trying an all grain with the new hops out of South America (Southern Star)