3 Gallon Rubbermaid & Beersmith

After many years of extract/grain brewing I finally made the foray into AG with a converted 3 Gallon Rubbermaid cooler to make a 3 Gallon batch. I was looking great through the pre-boil gravity. However, after siphoning the cooled wort into the carboy and adding the gallon or so of water (I do this because I have a 3 gal pot, so while I'd like to do a full boil I don't have the room) to come to the 3 gallons total, I mixed the two with some carboy swirling and had a gravity of 1.040 when I should have had a 1.053. Since I started with a BeerSmith Brewhouse Effeciency of 73% (first time so went with this number), my poor results essentially brought me down to 55%. I'm not sure how I could make it so good till late in the game and than slip so awfully. I left some wort in the bottom of the pot, as there was a lot of trub (it looked like a human brain was sitting down there)- but it couldn't have been more than a quart. Any ideas? Any advice would be appreciated.

One lingering thing that I'm having trouble getting an answer on is the initial strike temperature of the mash. I preheated the mashtun as I've often read to do, and through BeerSmith added 7.59 quarts of water at a strike temp 165.9F to get a mash temp of 154F. First I added the water to the preheated cooler, than stirred in the 6.07 lbs of grain. I than measured the temp of the grain & water and came up with 141F - way short of 154F. I had an equipment profile with the mashtun, is there anything I can do to adjust it to get closer to the target? Do you know any reason why it might be that off?


Thanks!
Mike

two things, what did you get your strike water up too? and what was the temperature of the grain?

what i do if i fall short of the temp. i want, i typically have another pot with some boiling water or close to, so you can add just enough to get it to that temperature, or the opposite, if its too high, add come cold water.

I don't preheat my mash tun (5 gal rubbermaid). I do use this calculator...
http://www.rackers.org/calcs.shtml
...and add 10 degrees. I put the heated water in the tun and let the temperature drop to the strike temp (usually 10-15 mins) and then dough in. I'm always at the desired mash temperature or no more than 1 or 2 degrees away.

Thanks so much for the quick replies. I appreciate the help, I know getting your equipment down for AG is a learning process, but getting some experienced intelligence to speed the process is great!

Estimated Grain Temp:68F

So I should have said in my previous email, when the strike water yielded a 141, instead of the targeted 154 I boiled a quart of water and got the temp to 153. I was very happy that after an hour the temp was the same - so the cooler itself worked quite well.

All things being equal the 165.9 strike water looks way too low, but all the independent calculators that I've seen online are around 170. My gut tells me with the difference I experienced I need to start up around the 180s. At least go up 10 degrees and have a couple of cups of boiled water at the ready to be safe as Rustbucket suggested.

You shouldn't need to start that high. I have everything built into my spreadsheet regarding strike temp etc... Typically always hit the temp just fine. Would recommend putting your water in the tun about 4 - 5 degrees higher than the strike temp (assuming you already preheated the tun). Allow it to come down to about 2 - 3 degrees above and begin adding your grains while stirring. Once fully mixed check your temp and you should be quite close.

Here is a link to my spreadsheet if you'd like to take a look at it:

https://www.homebrewtalk.com/f36/cps-brew-chart-1-0-a-213673/

A couple of things.
Firstly, if you are doing a partial boil with AG, then you are almost certainly going to get lousy efficiency. You need to sparge to very close to the full volume in order to rinse most of the sugars out of the grain.
Secondly, I checked out your strike water temperatures, and they looked about right to me. My calculations recommended 167.7F, but my grain temperature was at 60F.
You say you pre-heated the cooler. Like shelly belly said, the easiest way to do this is to add your sparge water about 10 degrees hotter than you need, and wait for it to cool down. I wouldn't try the rackers calculator as it gives results about 2 degrees greater than what I know works for me. If you pre-heat the tun, you do need to wait for several minutes (at least 10) to allow the tun to be warmed up. Also, if you preheat the tun, you need to express the weight of the tun as 0. If your thermometer is accurate, your volumes and weights are accurate, and you preheated the tun properly, then you would have got very close to the required temp of 154.

-a.

ajf said:

A couple of things.
Firstly, if you are doing a partial boil with AG, then you are almost certainly going to get lousy efficiency. You need to sparge to very close to the full volume in order to rinse most of the sugars out of the grain.

Click to expand...

I think this is the main culprit. If I understood correctly, you topped off in the carboy with water? If you were calculating in BeerSmith without taking into account adding water in the carboy, then that's why the numbers were so different. It sounds like BeerSmith wasn't considering an addition of water, especially if the preboil gravity matched.

Thanks for the info. Beersmith was absolutely aware of the top off water as it was built into the equipment profile. I am boiling 2.89 gallons of wort for a 3gallon batch, the water is replacing what is evaporating in the boil. Certainly, as ajf suggested a slightly bigger brewpot would improve my effeciency.

The next time I will not preheat, but put in slightly higher strike water and let it come to temp, than stir in the grains. Just in case I will have some hot water ready to bring a low temp up.