First biab

tomoncanterbury · October 07, 2017, 02:45:54 PM

Just finished our first ag biab brew day. I mashed in at 160F and mashed at 152 for 60mins. Ended up with 1.056 og and we were aiming for 1.067. Gave us an efficiency of about 67%. I was wondering if anyone could offer some tips on how to improve mash efficiency.

Thanks

mikegraham · October 07, 2017, 04:47:06 PM

Playing with the grain crush will help and make sure there is no dough balls in the mash. But with efficiency that is not bad for a first brew.

tomoncanterbury · October 07, 2017, 05:21:23 PM

Ah thanks for the tips. Maybe a finer crush on the grains. Also, my thermometer crapped out with 20 minutes left in the mash so I had to go by feel so better temperature control obviously.

mikegraham · October 07, 2017, 06:25:00 PM

I would bet the mash was done the conversion at that point. Finer crush will probably help but 67 isnt a bad efficiency for a first batch

robcoombs · October 08, 2017, 10:08:38 AM

I'm not a biab brewer but from what I've heard that method typically has a little lower efficiency.

It is important to track pre boil gravity as well to see if you are getting a good mash efficiency vs efficiency overall. For example, you can be very close on preboil gravity but off on OG. Which means you may need adjust your boil off volume etc within software like BeerSmith.

Sent from my SM-G935W8 using Tapatalk

feldmann · October 08, 2017, 01:31:22 PM

I'll echo what Rob said. I started all grain with BIAB and I used to get around that for efficiency. If you plan for it, its not a big deal.

Two Wheeler · October 09, 2017, 08:31:44 PM

Hey Tom,

I am a BIAB brewer and will agree with what everyone has said so far. My worst efficiency was 55%, my best was 78%. There are three things that really affect my efficiency. Crush, Time and draining.

For the crush, my mill tends to loosen up over time and when it does, my efficiency drops. If I have a bad efficiency day, I'll tighten up for the next brew day and it will usually improve it up to 10%.

Mash time- I know there is conflicting science on this, but I personally find that mashing for 90 mins vs 60 will help my efficiency.

Draining- it's hard to completely rinse the sugars out of the grains using BIAB. I have modified my process from the typical BIAB to include a rinse/sparge stage. I hang my bag from the rafters of my garage, over the pot. I have a ratchet pulley to help lift and keep it suspended. When designing my recipe in beersmith, I will put 3-4 gallons (for a 10g batch) in the "kettle top up" field. This makes the mash a bit thicker. Once the mash is over I will hoist the grain bag, then pour over the 3-4 gallons on top of the grain bag. This gets more sugars into the wort, and also allows you to make a bigger beer with your pot!

As the boys have said- it's really not the number that matters. At our scale it's not costing you much (other than pride

). My biggest issue is keeping it consistent. I don't mind getting 65% when I planned the recipe for that.

shazapple · October 10, 2017, 08:52:31 AM

I do a fairly fine crush and get around 72% efficiency most brew days. My crusher is cheap and the teeth aren't as grippy as they once were so I have to run things through with a wide gap, then the narrowest gap I can get.

I stir the mash a couple times and stick to a 60 minute mash window mainly because I'm impatient. I have had a couple longer mashes and they do seem to get better efficiency.

I used to "squeeze the bag" but now I just let it drain in a colander/bucket.

I use Brewers Friend and have my efficiency set to 70%, mainly so I can avoid doing all the little 'tricks' to keep my efficiency up. It means I end up adding more grain but that is fine with me.