BIAB strike water amount and yeast pitching

[lilbova3]

Hey all, have a few questions for ya.

I'm new to brewing and decided to jump right in with all-grain brewing. I've done one BIAB brew. Followed a clone recipe and cut it in half. I cut it in half because I do everything via stove top and am worried about getting a full boil. My clone's efficiency was pretty poor. I am using Brewtarget for my next brew and have lowered the efficiency to offset the BIAB and have upped my grain bill to hit my target OG.

First question, strike water amount. I found a website to help with this.

Double IPA (love my hops and ABV high)
Grain Bill: 8.8 lbs
Batch size: 3.5 gallons
Strike water amount 6.5
Boil size: 5 gallons (assuming 1 gallon loss per hour, I'm doing a 90 min boil that will leave me with around 3.5 gallons, right?)
Mash at 151-152. Mash out at 170.

Does that strike water amount sound right?

Second question. Since it's a smaller batch but I'm expecting a high OG, should I pitch one, one and a half, or two smack packs of yeast? I've read the higher gravity beers need more yeast. Is that correct?

Please help! Thanks in advance!

 

[dbkdev]

Hey all, have a few questions for ya.

I'm new to brewing and decided to jump right in with all-grain brewing. I've done one BIAB brew. Followed a clone recipe and cut it in half. I cut it in half because I do everything via stove top and am worried about getting a full boil. My clone's efficiency was pretty poor. I am using Brewtarget for my next brew and have lowered the efficiency to offset the BIAB and have upped my grain bill to hit my target OG.

First question, strike water amount. I found a website to help with this.

Double IPA (love my hops and ABV high)
Grain Bill: 8.8 lbs
Batch size: 3.5 gallons
Strike water amount 6.5
Boil size: 5 gallons (assuming 1 gallon loss per hour, I'm doing a 90 min boil that will leave me with around 3.5 gallons, right?)
Mash at 151-152. Mash out at 170.

Does that strike water amount sound right?

Second question. Since it's a smaller batch but I'm expecting a high OG, should I pitch one, one and a half, or two smack packs of yeast? I've read the higher gravity beers need more yeast. Is that correct?

Please help! Thanks in advance!

What are you losing 1.5 gallons to before you even start to boil? Or is 5 gallons the amount going into your fermenter, and not your boil volume?

 

[lilbova3]

Losing 1.5 gallons from grain absorption and mash. Is that not right, too much you think?

 

[dbkdev]

Losing 1.5 gallons from grain absorption and mash. Is that not right, too much you think?

You shouldn't be losing any to evaporation during mash, since your pot should be covered / insulated. If you are losing 1.5 gallons to the grain bag you take out, you should be letting it drain more/squeeze more out of it back into the kettle. You are talking about BIAB right?

 

[G-Hog]

I do 5 gal BIAB batches and start off with 7.5 gals of water. I only do a 60 minute boil and I end up with a little over 5 gal in the fermenter. And no way should you be losing 1.5 gal to grain absorption.


Sent from my iPhone using Home Brew

 

[lilbova3]

Thanks for the help all. I did a little more researching and I'm still finding out info, there's so much out there, and found a great BIAB website with an excel spreadsheet. Really like it and is a little more explanatory I feel.

Just ordered stuff for my next batch, hope it goes well.

 

[dobe12]

I believe a normal system (non-BIAB) absorbs about .1 - .125qt/lb. BIAB is less, but all depends if you squeeze and how much. I BIAB and estimate around .0825qt/lb of absorption when figuring out my mash/sparge water.

 

[tmendick]

first and foremost, what efficieny did you get?.


Two questions that help ususally

1. How is your crush?
2. Did you squeeze the bag?

To answer your yeast question, using my 80% effeciency I get 1.062 as the starting gravity. According to http://www.yeastcalculator.com/ you should need 151 billion cells, the date the yeast was manufatured effects the amount of cells in a pack so I would still assume almost 2 pack unless you get a really fresh one.

Good luck and welcome to BIAB

 

[lilbova3]

Efficiency was only around 55%.

Pre ordered my grain crushed. Didn't crush it any extra even though I've heard more crushing could help efficiency.

Yes I squeezed the bag. Maybe should try squeezing more next time.

Also with it being my first time I had an issue controlling my mash temp. I was worried about keeping a constant temp so I kept it over the heat. Found out the hard way that's no good. I caught it late and was around 170* (because of keeping my kettle on the heat) instead of my 151* I wanted. Next time I know to take the kettle off of the heat, wrap it and cover it. This could have led to less sugars available as well.

 

[KIAKillerXJ]

Efficiency was only around 55%.

Pre ordered my grain crushed. Didn't crush it any extra even though I've heard more crushing could help efficiency.

Yes I squeezed the bag. Maybe should try squeezing more next time.

Also with it being my first time I had an issue controlling my mash temp. I was worried about keeping a constant temp so I kept it over the heat. Found out the hard way that's no good. I caught it late and was around 170* (because of keeping my kettle on the heat) instead of my 151* I wanted. Next time I know to take the kettle off of the heat, wrap it and cover it. This could have led to less sugars available as well.

Yea, thats WAY to hot. Probably good reason for your poor efficiency.

 

[tmendick]

How long did you mash for? lots of the BIAB orginators recommed a 90 minute mash.

 

[lilbova3]

I mashed for 70 and mashed out at 20 compared to a normal 60 and 10. You think 90 min would be more beneficial?

 

[tmendick]

shouldn't make that big of a difference. I would say find a LHBS (Local HomeBrew Shop) and crush grain there, so you can ask about grain crush in person. In my experience, online shop crushes vary too much.

Mashout shouldn't be ncessary at all though. I just do a 90 min at 151ish mash debending on style.

 

[lilbova3]

I don't have a LHBS unfortunately. Just have to hope for the best I guess.

 

[ElJefeBrews]

I do 1 gallon BIAB-ish brews and I use 12 cups water for mash and 20-21 cups for sparge. After a 60 minute boil my volume is usually perfect. Hope that helped

 

[dobe12]

If crush is the issue, which I assume it is playing some part in 55% eff, you should get your own mill. The Cereal Killer is only $100 w/free shipping. I got one last fall along with a 10 gallon pot and larger grain sack and my efficiency jumped from 70'ish to 80-85% for average grain bills.

As for mashing times, I ran an experiment last week where I checked gravity with a refractometer and saw that conversion was complete between 30-45min. Now, I realize there are TONS of factors playing a role and yes longer mashes will yield higher efficiency in most cases, but in general I believe the majority of conversion happens in under an hour. Actually a large portion of conversion happens in the first few minutes (1.036 at 2.5min into mashing, 1.054 at 45 & 60min), but it slowly tapers off from then until about the 30-45min mark. I also completely understand these were just my findings from one mash. Water/grain ratio, pH, grist, temp, time, etc..... are all factors.

 

[dbkdev]

Efficiency was only around 55%.

Pre ordered my grain crushed. Didn't crush it any extra even though I've heard more crushing could help efficiency.

Yes I squeezed the bag. Maybe should try squeezing more next time.

Also with it being my first time I had an issue controlling my mash temp. I was worried about keeping a constant temp so I kept it over the heat. Found out the hard way that's no good. I caught it late and was around 170* (because of keeping my kettle on the heat) instead of my 151* I wanted. Next time I know to take the kettle off of the heat, wrap it and cover it. This could have led to less sugars available as well.

Heat it to like 162, kill heat, stir in grain slowly (temp should drop to like 151/152) cover/wrap. I bought some hot water heater tank insulation, cut it to the shape of a jacket for my pot, and covered the yellow insulation coming out of my cuts with duct tape for a smooth edge. I also made a lid cover, not in the picture below.

Additionally, I don't have a good spot for a pulley, so had to come up with another solution. I had an old 5 gallon pot laying around, and I usually plant peppers/tomatoes in pots on my deck. I took a pot stand (similar to the one pictured below, but with less of a grate), and placed that over my 5 gallon pot, legs surrounding it. Took out my grain bag after mash in held it for a minute to drain over my kettle, than transferred it to sit on top of the 5 gallon pot. Squished/squeezed it a few times, and let it drain, eventually added back in after i was satisfied i had enough out of it, while raising my temp to a boil.

 

[lilbova3]

I've read my strike needs to be somewhere between 159-162. So I will try to get it in that range. Thanks all for the help. Brew day should be Tuesday.

 

[jtratcliff]

Your poor efficiency was almost surely due to your high mash temps.... You're denaturing the amylase enzymes (both alpha & beta) at those temps and not getting fermentable sugars.

Don't over compensate with too much extra grain expecting low efficiency again. If you keep your mash temps in check, you'll do a lot better.

Use a mash calculator. It can tell you where your temps need to be for given amounts of water and grain. I use the mash wizard in Brewtarget and find it to be pretty accurate.

 

[emachine]

I did the exact same thing with mash temps on my first AG biab. My efficiency turned out to something like 35%. Putting my pot in the oven (turned to low) was the trick that helped me get temp loss under control.

 

[lilbova3]

I'm using the website BIABRewer now. Looks pretty legit, very in depth. Any other BIABers ever use that site and their excel spreadsheet calculator for their BIABs?

 

[JBCSL]

I also do 3.5 gal batches BIAB. One thing I found essential for getting good efficiency is using a frying cage to keep the bag off the bottom. I usually get at least 75% efficiency that way. One time I skipped the cage on a lazy brew day and ended up with 55%, all other things being equal. Typically for a grain bill of 8 and a half lbs I would use about 4.5 gal strike water, with at least a gallon of that water under the cage.