First BIAB-just a few questions please?

[Pelican521]

I'm going to do my first partial mash today with the BIAB method. It's an Oatmeal Stout kit from Northern Brewer. I'm pretty excited!

The instructions say to heat 5 quarts of water to 164, mash grains for an hour, then heat mash kettle to 170 and pull out bag and drain. Next to sparge with 5 quarts of 170 slowly. Finally to top up the boil kettle with your normal boil volume and proceed as you would an extract kit.

My plan is to wrap a heating pad around my kettle and wrap it up with a sleeping bag to hold the temp for the hour. I tested the heating pad last night and it got up to 140 after an hour so I think this should help a lot with holding the temp.

Do you have any comments or tips on any of these instructions as far as water volume and strike temp/etc.

Also, as far as the boil goes it says to top up to your normal volume, is 3 gal ok? I don't want to go full boil cause I don't have a chiller and don't want to take too long cooling with my ice bath.

Thanks,

 

[mysteryshrimp]

The heating pad is a good idea. That's how I make yogurt. I still do brew in a bag occasionally, and when I do it's in a small igloo cooler.

164 should be fine, but keep an eye on temperature to make sure that it drops to below 158 after adding the grains. above 158 for any length of time, and you'll start denaturing enzymes.

For a stout a partial boil is fine. There is a technical limit to hop utilization, so an IPA or anything else that's fairly bitter could be an issue, but a stout is fine.

Boil some water now, put it in the fridge. The colder it is, the faster the chilling.

 

[ZombieBrew83]

Check out the calculators on tasty brew:

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Hitting your mash temp is delicate balancing act. I would aim low and add more heat if necessary. Assuming you are doing this on a stove. I BIAB and mash with 2qts/lb of grain even when doing a partial mash. It is always better to boil as close to full volume as mysteryshrimp illustrated above.

Did you get your grain double crushed? Or did you crush it yourself? This can be a huge difference in your efficiency.

 

[unionrdr]

I do PB/PM BIAB & don't have any issues with hops utilization. I usually mash 5lbs of grains in 2 gallons of water. I heat it to 152-155 with a cake cooling rack in the bottom of my BK/MT with a 5G paint strainer bag. At 150F,I pour in the grains & stir with my plastic paddle to break up dough balls & get the grains evenly wetted. When the temp comes up where I want it(I have a floating thermometer lashed to the kettle handle in the mash),I put the lid on. Then place it in my winter hunting coat & wrap it up for the 1 hour mash.
Since my BK/MT is 5 gallons (20QT),I heat 1.5G of water to 165-168F to sparge with while the mash is working. I place my SS collander on top of the BK/MT & sparge to get boil volume of 3.5 gallons. Since 5lbs of grains equals a 3lb bag of DME,it's about 50% of the total fermentables & I use that for all hop additions. I add all the extract (3lb plain DME or 3.3lbs plain LME) as a late addition to keep the color light & flavor cleaner.

 

[cherrob123]

I have only brewed with the partial mash method. I have about 25 batches under my belt and have honed my technique down pretty well.

I mash with three gallons in an igloo water cooler at 156 deg. I mash with my grains in a muslin bag. Once I am done with that, I transfer back into the boil kettle and sparge with 2.5 gallons of 170 degree water. That's my boil volume.

I have found that if I boil moderately to lightly, my target OG comes out right on the nose. I lose too much volume if I boil vigorously.

I am building a mash tun with a false bottom out of a 6 gallon Igloo and I intend to start all grain brewing this summer.

 

[Pelican521]

Thanks guys, very helpful stuff.

I was kind of worried about the strike water being so hot. Just to clarify, there's only 4 lbs of grains to the 5 qts of strike water.