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BIAB 7.5 Gallon Kettle

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illomenbrewery

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Hey whats going on guys I have a noob question, but I am new to BIAB. I want to BIAB using my 7.5 gallon kettle, but from what I have read and seen I think I would be mashing/boiling pretty close to the top of my kettle. What would you recommend? Should I just take 1 gallon of water off of the boil recipe and add it in when transferring wort to carboy (pretty much like when extract brewing)? I do have a burner I use outside for brewing. I would be brewing different styles of beer from low to high gravity.

Thanks for the help!
 
I use a 30qt also, and mash up to 16lbs. But I don't mash in the total water volume, instead doing a dunk sparge to top off. It requires another pot, but that pot can be smaller. If the sparge pot is too small to hold the other half of the water plus wet grain, then dunk, drain, pour more water. I sparge in hot water, but some claim that cold water works as well. This should also improve your efficiency.
 
JohnSand describes my method exactly. If you don't have a pot, a food safe 5 gallon bucket also works well for the dunk sparge. I've been using cold water recently as it is then easier to squeeze the bag. The downside is that it will take longer to heat to a boil.

To provide more exact numbers, I typically mash with 5 to 6 gallons (for a big beer, I could mash with even less; on very small beers (OG 1.030) I can do full volume BIAB). I keep (8 - mash volume) gallons available (typically 2 to 3g) for the dunk sparge. After water loss in the grain, I have about 7 gallons at boil time (probably a little less given thermal expansion of the water). After boil and cool, I have about 5.5 of wort + trub (all of which goes in the fermenter).

Perhaps the trickiest part here is boil overs. After hot break, I add Fermencap-S to tame the foam and liberally apply cold water from a spray bottle when adding hops. So far, 30+ brews and no boil overs. Of course, I've just jinxed myself for tomorrow's brew day...
 
One additional point, if you wanted to skip the dunk sparge, it only adds a very small amount of additional sugar (mashing with about 5.5 gallons, I got 4.5 gallons at about 1.070; the dunk sparge contributed 2 gallons at 1.015 or so). Throw in an extra pound or two of base grain, and you could just as well skip the sparge step.

I might try this tomorrow....
 
I'm currently doing 5 gal BIAB batches in an 8 gal kettle (5.5-5.7 gal to fermentor.) I managed a 1.073 beer with a 14 lb grain bill, just barely (did have some slopping during mashing and a minor boil over.) Any bigger beer would need a larger kettle (or DME supplementation.) I wish I would have gone for at least a 10 gal kettle, and am now looking at a 16 gal for my next upgrade. That would give me plenty of space for very big beers at 5 gal, and up to 1.065-1.070 beers at 10 gal. (cross posted from here: https://www.homebrewtalk.com/f244/15-19-gal-kettle-5-gal-batch-482228/#post6265483)

I should add that I have 4 inches of "dead" space in my BK below my bag due to the basket I use to hold the bag (I have a 32 qt Bayou Classic SS pot with perforated basket.) I pour sparge with the basket suspended above the BK.

Brew on :mug:

BIAB Ladder Hoist 1.jpg
 
JohnSand describes my method exactly. If you don't have a pot, a food safe 5 gallon bucket also works well for the dunk sparge. I've been using cold water recently as it is then easier to squeeze the bag. The downside is that it will take longer to heat to a boil.

To provide more exact numbers, I typically mash with 5 to 6 gallons (for a big beer, I could mash with even less; on very small beers (OG 1.030) I can do full volume BIAB). I keep (8 - mash volume) gallons available (typically 2 to 3g) for the dunk sparge. After water loss in the grain, I have about 7 gallons at boil time (probably a little less given thermal expansion of the water). After boil and cool, I have about 5.5 of wort + trub (all of which goes in the fermenter).

Perhaps the trickiest part here is boil overs. After hot break, I add Fermencap-S to tame the foam and liberally apply cold water from a spray bottle when adding hops. So far, 30+ brews and no boil overs. Of course, I've just jinxed myself for tomorrow's brew day...


So mashing 5-6 gallons, and 2 gallons for dunk sparge. I am trying to find some videos of dunk sparging, but are you just taking the Bag and dunking it in the sparge pot like a tea bag? If so how long would you dunk it for? I am thinking of getting a 10 gallon cooler and just mash in there. I know I could technically just do all grain the regular way if I get the mash tun, I just like the idea of having a bag easier cleanup etc. Plus if i go away from BIAB I will need to buy a cooler conversion, false bottom, and another pot or cooler. The thing i am afraid of is trying to boil 6.5 or 7 gallons of wort in a 7.5 gallon pot. i am guessing there would be a really big chance of boilovers once the hops are introduced.
 
I dunk sparge by putting the grain bag into the other pot with hot water and let it sit. While the boil kettle is heating to boil, I stir the grains to help extract sugar. I add the sparge to the boil a little at a time, making up for boil off. I also "squeeze" the grain bag by putting it in a colander in the sparge pot and pressing on it with a plate. No burns, no sticky hands.
You are right to worry about boil-overs, I had three yesterday. It's no big deal outside, but a terrible mess on a stove. Watch your heat and your pot, keep a spray bottle and spoon handy. Add your hops a little at a time, don't just dump them in. You can add the sparge as you go along. This knocks down your boil briefly, it's not a big deal. I prefer to end up a bit low on volume, you can always add water if you need. This makes for an easier boil. The last few times on my stove, I hit my numbers and volumes pretty well. It does take practice. I'm still dialing in my process on the patio burner. If you are on a stove, you could also split your boil into two pots, with less worry of boil-over.
 
So mashing 5-6 gallons, and 2 gallons for dunk sparge. I am trying to find some videos of dunk sparging, but are you just taking the Bag and dunking it in the sparge pot like a tea bag? If so how long would you dunk it for?

I put the bag in an empty 5 gallon bucket and then poor water over it until the bucket is full. Any extra water not used in the "dunk", I add directly the boil kettle. I usually leave the bag in the bucket for 10 minutes, give or take, while I do some clean up or measure out hops.

I am thinking of getting a 10 gallon cooler and just mash in there. I know I could technically just do all grain the regular way if I get the mash tun, I just like the idea of having a bag easier cleanup etc. Plus if i go away from BIAB I will need to buy a cooler conversion, false bottom, and another pot or cooler.

Use a bag in a cooler instead of a manifold is a perfectly valid way of lautering. If I was really committed to making 5 gallons of a barley wine, I could see myself doing this. For anything lower ABV, I don't think it is strictly necessary.

The thing i am afraid of is trying to boil 6.5 or 7 gallons of wort in a 7.5 gallon pot. i am guessing there would be a really big chance of boilovers once the hops are introduced.

Again, I've done 30+ stove top batches with no boil overs in a 30qt pot. Try to keep the volume at about 28qt or less to start. Moderate the heat when adding hops. Go slow. Use a spray bottle to control foam. I recommend Fermcap-S/anti-foam drops.
 
Success! I tossed in an extra pound of grain and came in just a touch high on my OG without the dunk sparge.
 
Success, yay! Did you do a dunk sparge and read the gravity? I put a false bottom in my 5 gallon bucket, (the drilled bottom of another 5 gallon bucket) and there is almost no dead space. I mash in my BK, put the bag into my Zapap tun, then pour in the BK water, drain my first runnings off and then fly sparge until I hit my desired O.G./volume, and then see if there is any sugar left in the grain to make a starter out of. I don't have an insulated mash tun, and it is one extra step doing it this way, but my beers are consistent, and for that I don't mind.
 
Success, yay! Did you do a dunk sparge and read the gravity?

I didn't dunk sparge this time. I just drained the bag and added top off water to get to full volume for the boil.

In the past, when I have dunked, the sparge seemed to contribute less than 10% of the total sugars. Adding an extra pound of base grain is about as effective.
 
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