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Old 03-21-2013, 04:48 AM   #1
Mar 2013
Posts: 7

I’ve been reading threads here for a while and tried to gain as much info as I could without creating useless threads. That being said, I would appreciate any help/insight you guys could offer.

I use RO water and add small amounts of gypsum and sodium choloride, is this best practice? The only other water I have access to is a natural spring 3 miles away or softened water out of my faucet. All the water in my building is softened.

I have about nine 1-gallon BIAB batches under my belt. Mostly Pale ales, IPAs, and even a double IPA. It’s an awful lot of work for such a small amount of beer. I just recently purchased a 30 quart boil pot, (only 13 inches of clearance from stove top to bottom of microwave) and a nice BIAB bag from Wilserbrewer (thanks again!). I am looking to do some 2.5 and 3 gallon BIAB batches, but want some insight before I do my first batch. I am trying to dial in my process.

I currently struggle with MASH temps and end up babysitting my kettle the whole time. I will notice the temp lowering, and turn on the lowest heat setting for a couple seconds then turn it off to get the temp up. Then I stir around the grain. My last 2 batches I would lift the bag and the overall temp would rise and had a reading of 160ish from near the bottom where the grain was just sitting... The overall water temp around the middle was reading 152 before hand and dropping. Is this common? I assume a false bottom type thing would help prevent this as well as improve water circulation. Maybe one such as this:


Also I have 2 thermometers. A standard mercury thermometer and a metal probe with dial. The metal probe with dial regularly reads about 3-5 degrees higher than the mercury one… Did I get a bad thermometer? I wouldn’t want to think I am mashing at 154 and have it actually be 158, that would be bad news.

I have been doing a double crush of my grains and upping the grain bill by about 15%, but my last 3 batches I have over shot my O.G. by a couple points; .176 actual versus .170 in recipe, etc. Is this cause for concern? I typically do a 70 minute rest in the low 150s, and then a 10 minute 170 rest (mash out). Then I let the bag drain into a sieve that sits in a separate kettle and once I get my wort close to boiling I add those runnings back in. I don’t currently sparge and apply very little pressure to bag when its draining. Should I be worried about a slightly higher OG, anything I should adjust?

I have tried a couple different fermentation styles with my 1 gallon batches. Leaving in primary until bottling, dry hopping in primary vessel once fermentation “complete”, or racking to secondary and dry hopping in secondary. I didn’t notice much difference from either method in my beers. However moving to 3 gallon I am worried about headspace…
A 3 gallon glass carboy would be nice if I use secondary, but leaves little room for blow off in the case of a 3 gallon batch. A 5 gallon bucket leaves lots of room for primary, but I don’t think I can dry hop in it because if I open the lid and reintroduce oxygen, there may not be enough CO2 to push all that new oxygen back out… What do other people use for their trial/half batches? Is it best to use a 5 gallon bucket for primary, rack to a 3 gallon secondary to dry hop (usually 10-14 days later for me), dry hop per schedule, then rack to bottling bucket?

The only nice thing about the 1 gallon batches was I was able to have several different types of beer in the fridge at once. Moving to 3 gallon I wouldn’t be able to fit 2-3 different batches in the fridge all at once. My question is, being that I mostly do IPAs with hop forward flavors, can I just put half the bottles in the fridge after 3 weeks of bottle conditioning. And leave half bottle condition for another week or so? I assume no ill effects will happen, but at one point will I start to lose the hop flavors? I have tried to save an IPA for 6 months, and it was very malty at that point so I know 6 months is too long haha.

I apologize for the super long post, but would appreciate any feedback/insight/suggestions/comments etc.


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Old 03-21-2013, 05:05 AM   #2
Sarge's Avatar
May 2011
Sherman, Tx
Posts: 135
Liked 6 Times on 4 Posts

Welcome Miss!!!
I have done several small BIAB batches and the best way I have found to maintain mash temp is to place the mashtun in the oven. I'll preheat the oven to 170 (lowest mine will go) and then turn the oven off and then put in the mashtun. Mash temp rarely drifts.

Originally Posted by miss0033 View Post
I currently struggle with MASH temps and end up babysitting my kettle the whole time.

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Old 03-21-2013, 05:32 AM   #3
Jul 2012
Seattle, Washington
Posts: 2,104
Liked 183 Times on 158 Posts

Check out the water primer post in the brew science section.

As for your temps, try not to heat the pot. Get it to the right temp, and wrap it with a blanket or use a cooler to mash in. It's OK if it goes down a couple of degrees, and if it goes more than that, it's because you're lacking insulation.

Try to control your fermentation temps. It's really important, and hard to get a handle on. The good thing about smaller batches is they're easier to control. Put the whole carboy in a basin of water. This will help stabilize the temp. Take wort temp readings by attaching a remote thermometer to the outside of the carboy, and then covering it with insulation.
Then you can control the temp by adding ice or wet towels, or warming by turning up the heat or adding warm water. The warm water won't last long, so adding a small heater to the room is better.
The idea is to ferment at the lower end of the range (check the range of the yeast you are using on-line) until the action slows/krausen drops, then raise a degree per day until your at the upper range. Let it sit on the yeast for 3 weeks before even thinking of moving it. It will clean up the beer. Temperature control will greatly improve your beer.
Keg #1: Brown Bomber Bourbon/Oak Vanilla Porter
Keg #2: The Bollocks ESB
Keg #3 Lawnmower APA
Fermenter: Empty
Bottled: Mjolnir Mead, Lazy Daze Hefe.

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Old 03-21-2013, 06:36 AM   #4
Dec 2010
Northern California
Posts: 99
Liked 18 Times on 13 Posts

No worries about all the questions. No matter how many years you do this stuff, there are always more things to learn.

For BIAB mashes, the bigger and thicker the mash, the more stable the temp will be. Hopeful as you start brewing larger batches, the temp will maintain a little better/longer. Insulation is key if it continues to drop tho.

Regarding fermentation, I brew mainly 1-3 gallon batches. While there is a rampant fear of leaving too much head space and over-oxygenating your beer post-fermentation, CO2 is heavier than ambient air and will most likely remain blanketed over your beer even if you open up the top and throw in some dry hops. If you're worried tho, you can always put in the hops towards the end of primary fermentation, making sure that the CO2 fills the gap.

You don't need to put all of your fermented, bottle-conditioned beers into the fridge. In fact, some of them would probably improve with a little aging (at cellar temps preferably--between 50-60F). I just had a Belgiam Golden Strong I brewed last March that hadn't ever been in a fridge before last week and it tasted magnificently. If you put them all in your fridge, they won't age much, if at all. And if you calculated your priming sugar correctly, and waited to bottled till fermentation was completely finished, then you should be totally fine.

And about that thermometer. If you're at all unsure about its accuracy, you can calibrate it two ways:

1) COLD: Fill an insulated cup with crushed ice and then with water. Wait a few minutes, put the stem of the thermometer in the middle of the cup, avoiding the sides and bottom. It should read 32F. (Accurate to 0.1F)

2) HOT: Boil some distiller water an test it. It should read 212F
(Accurate to 1.0F)

The ice method is faster, safer, and more accurate.

Happy brewing!
Check out my latest homebrewing thoughts, recipes, tastings, and happenings at Ten Bottle Brewing. Drinking, researching, and brewing just about every style, with an emphasis on the bacteria-laden variety. Enjoy and brew on!

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Old 03-22-2013, 07:14 PM   #5
Mar 2013
Posts: 7

Thanks for the responses guys!

So I might give the oven a try, but 200 is the lowest my oven goes... So I am going to first try going 1 degree above my desired temp, wrapping in blankets/towels and not worrying about a 3-4 degree drop over the 60-70 minutes. I also assume 4.25 gallons or more is going to hold temps much better than 2.5 gallons. Plus my bigger brew kettle is a much nicer kettle with an 8 mm sandwich bottom. I didnt quite get an answer to the false bottom question, but I will probably get one and play with it because its only about $8.

Once I am at my temp should I remove it from the burner? Or just turn the burner off and leave it on there? I have been removing it from the burner (which could help explain heat loss I guess), because I assumed even while burner is off, it was still quite warm and could be heating my mash higher than I want...

Ran the cold test on the thermometers. Mercury was dead on at 32 deg, just ever so slightly above. And the metal probe read 36 degrees, and is probably going in the trash, bad $16 "investment." I just cant afford a nice $80 digital probe yet...

Right not my fermemters sit in a basement that stays a pretty steady 64-66 degrees. But I will try the water method you've described as well. I havent really monitored ferm temps, other than just the overall room temp. I bought some "fermometer" strips for my new primary.

I will also try adding a week to primary. I have currently been doing 12-14 days then going to secondary, but now I will try going 21 days primary, adding the hops to start secondary, and doing secondary only as long as dry hop (usually 10-12 days), then bottle and let the bottles sit for 3 weeks as well.

I would also like to try cold crashing before bottling, because I havent done that yet, to see if that improves my beer. I (knock on wood) havent had any "bad" batches yet per se, just lookign to make better beer and more of it!

Thanks again guys!

Brewbob, I read through your blog a bit, cool stuff. I noticed you use the whirlfloc tablet for some of your 2.5 gallon batches. I assumed since it was meant for 5 gallon that I couldnt use it or would have to break it in half. Do you use the whole tablet or break it in half?

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