First AG batch in the books...

[bgrubb7]

Well, my first AG batch was a little rocky, but successful nonetheless. Now I know what every means by getting your processes down first, then worry about the little details!

My temp calculations (used the tastybrew.com online calculators) were nowhere close.

6.625 lbs grain bill
1.25 ratio.

My 153 target mash gave me a strike temp of 167. After reading an earlier post, I decided to heat a little hotter to 170, then dump into my cooler-tun to preheat, then let cool until it got down to 167. Then I dumped my grains in and stirred, but my temp only dropped to around 158. No biggie, I dumped some ice in and stirred till it got down to around 153.

10 minutes later, by mash temp had dropped 5 degrees! (yes the lid was closed) I drained off some of the mash, reheated and dumped back in. Had to do this one more time to get back up to 153. 10 min later, I dropped another 5 down to 148. Drain a little, reheat, redump and repeat. After about a half hour of doing this, I was at 154, and was finally holding my temps. The next half hour saw a drop to 151.

I think some of my problem is in the fact that my cooler is almost too big. 50qt cooler, with a 6.625 grain + mash water only filled 1/3 of the cooler. Plus even though I preheated with my strike water, it wasn't enough. The cooler was in the unheated garage all night, so it was ice cold. Dumping in the strike water only heated the bottom half of the cooler. I think it took the first 30 min of the mash for the internal temp of the entire cooler to even out, since the last 30 min didn't drop near as much. I'm thinking a smaller cooler may have also been a little more efficient??

Anyways, onto the sparge. I split my sparge into 2 separate 2 gal batches. First batch I heated to 180, and dumped. I undershot it at around 160 due to the fact that I had let too much time pass, and my grain temps had dropped to around 140 something. Second sparge I overshot it at around 175 (run get more ice), by overcompensating from my first batch with hotter sparge water. Anyways, towards the end of the second sparge, I tasted the runoff, and it tasted about right, very little sweetness, but not astringent. Cooled down my sample wort, and my pre-boil gravity was right on the money to Beersmiths estimated 1.030.

So when checking your efficiency in beersmith do you use your pre-boil Gravity or post-boil? If I use pre-boil, then I'm right at 75%, if I use post-boil (1.038) then I'm way over that.

Overall it was a success, but I was a little on edge for a while chasing my temps all over the place. It would have been much easier if I had the ability to heat my mash vessel. I could pick up another boil pot and convert to a mash tun. I've got enough stuff to make another shutoff valve/SS hose setup. I would rather use the cooler method if possible, as I really don't want to have to babysit a flame for an hour in order to keep my mash stable. The 50qt cooler I used is actually a good one - it will hold ice for days on end, so I just didn't think that it would loose temps like that. I have some smaller coolers that I could try, if that would be better.

 

[njnear76]

So when checking your efficiency in beersmith do you use your pre-boil Gravity or post-boil? If I use pre-boil, then I'm right at 75%, if I use post-boil (1.038) then I'm way over that.

When taking the gravity, you have to account for the amount of wort.

For example: Preboil 1.038 with 7.25 gallons of wort would be equal to post boil: 1.050 with 5.5 gallons of wort.

To calculate efficiency, you have to take in account the amount of grains as well.

Here's an example:

1.0 lb Chocolate Malt
1.0 lb Crystal Malt
1.0 lb Munich Malt
0.5 lb Black Patent
8.0 lb British Two Row

7.25 gallons of wort gravity: 1.043
5.5 gallons of wort gravity: 1.057

You can calculate your efficiency pretty easily by changing the wort volume in beer smith to equal what you collected, then changing the efficiency in beer smith until your real gravity matches the beer smith gravity. In this example I got 74%.

To heat up your mash tun, I would make sure that you swish the water around a lot. I let mine sit for about 5-10 minutes until it warms up.

Mike

 

[bgrubb7]

I'm at work, and don't have Beersmith handy, but here's the grain total:

6 lbs. UK Mild Ale
0.125 lbs. UK Chocolate
0.25 lbs. UK Amber
0.25 lbs. UK Brown

My recipe called for 6 gal preboil, and 5.25 postboil. with a preboil of 1.030 and a postboil of 1.034

My actual preboil was 6.25gal @ 1.030, and a post boil of 5.25gal @1.038

So I adjust my Boil volumes in Beersmith to what they actually were, then change my efficiency numbers till the recipe gravity matches my actual post-boil gravity?

 

[Lil' Sparky]

After you add your strike water to your cooler, let it sit for a bit with the lid closed.

Then after you add your grains, stir until you think everything's mixed really well, and then stir some more. I think that's the key to getting really stabilized mash temps.

Probably what happend is you took the temperature before the mash had really stabilized, then you added the ice, which will take some more time to stabilize, so you probably added too much, and the cycle continues, and continues to frustrate you.

How are you measuring your mash temps?

 

[njnear76]

I'm at work, and don't have Beersmith handy, but here's the grain total:

6 lbs. UK Mild Ale
0.125 lbs. UK Chocolate
0.25 lbs. UK Amber
0.25 lbs. UK Brown

My recipe called for 6 gal preboil, and 5.25 postboil. with a preboil of 1.030 and a postboil of 1.034

My actual preboil was 6.25gal @ 1.030, and a post boil of 5.25gal @1.038

So I adjust my Boil volumes in Beersmith to what they actually were, then change my efficiency numbers till the recipe gravity matches my actual post-boil gravity?

76% efficiency @ 6.25 gallons 1.030
80% efficiency @ 5.25 gallons 1.038.

I think that the reason why there was such a differance between the 6.25 and the 5.25 gallons is due to a small grain bill.

Great job though. Anything above 75% efficiency is very good.

Looks like a good 3.6 - 3.7% brew.

I usually only take the pre-boil gravity. You can try my calculator/dirctions if you like. This might take out some of the guesswork on brew day.

By the way, in adition to what Sparky said, you might want to get a good digital thermometer.

 

[bgrubb7]

Probably what happend is you took the temperature before the mash had really stabilized, then you added the ice, which will take some more time to stabilize, so you probably added too much, and the cycle continues, and continues to frustrate you.

Looking back, I think that is exactly what happened! I was making corrections before corrections needed to be made. Plus I didn't preheat well enough. I used a standard dial type brewing thermometer that was calibrated to 33 in ice water before hand. A digital unit would be better, as I assume it would instantly show any temp changes during a stir, and would indicate wether or not the entire mash temp was stabilized.

I ran the recipe and boil numbers through Tastybrew.com and using the post-boil volume and gravity I'm coming up with 82% total efficiency. Pretty amazing considering I spent most of the mash chasing my tail!

 

[Lil' Sparky]

The other undesirable thing about the dial thermos is that you have to open the cooler to take a peak. Probe thermos are nice in that regard, but most of them aren't waterproof. If you go this route, do a search on waterproofing the probe with silicon tubing. You'll be happy you did.

Really, it sounds like you had a very good first AG brew. I bet next time you don't have these same problems, and you can be concentrating on the cold homebrew in your hand instead of the temp fluctuations of your mash.

 

[bgrubb7]

Hope your right, Sparky.

Ya, digital thermo is on my list right now.

So the size of the cooler really shouldn't matter as long as it's preheated good enough?

 

[missing link]

Eliminating dead space in your cooler will help it hold temps longer. There is a member here that made a styrofoam float that floats on the water to help slow the temp loss.

My 5 gallon cooler loses almost nothing once heated with 5 gallons of water in it. My 12 gallon loses temp quickly when it is only half full, especially if I open it to stir. Luckily I am using heating elements so any temp drop can be adjusted by just plugging the cooler in and stirring for maybe 2 or 3 minutes.

I have 2 all grains down now and I am still getting my steps in order.

Linc

 

[bgrubb7]

Eliminating dead space in your cooler will help it hold temps longer. There is a member here that made a styrofoam float that floats on the water to help slow the temp loss.

My 5 gallon cooler loses almost nothing once heated with 5 gallons of water in it. My 12 gallon loses temp quickly when it is only half full, especially if I open it to stir. Luckily I am using heating elements so any temp drop can be adjusted by just plugging the cooler in and stirring for maybe 2 or 3 minutes.

I have 2 all grains down now and I am still getting my steps in order.

Linc

You wouldn't happen to have any pics/links to your setup or a similar one would you? I'd love to be able to add heat to my tun, but want to stick with the converted cooler setup for its heat retention properties, rather than a converted boil pot & flame.

 

[jds]

There is a member here that made a styrofoam float that floats on the water to help slow the temp loss.

I've seen ping pong balls (well, they were 'industrial use' floats for parts washers, but basically, ping pong balls) used for the same thing. They insulate the liquid surface well, and help reduce heat losses through the surface.