1st BIAB by the Numbers

[Culln5]

Hey Guys,
I completed my first BIAB yesterday and here's what took place:

• 8 Gallon Pot
• 11.2lbs of Grains
• Mashed In at 153 with 7 gallons of water
• Mashed for 60 mins at 148 (stirring occasionally)
• Pre-boil gravity was 1.046 (Beersmith estimate was 1.050)
• 60 minute boil
• Hung and squeezed the ever-loving crap out of it
• Measured OG of 1.064 (Beersmith estimate 1.056)
• Measured Efficiency 78.9% (Beersmith set at 72%)

I was pleased that I was close to my pre-boil estimate but confused why I was so far over my OG. Then I started to think..... My pre-boil was taken before the edition of 1.2 lbs of rice extract syrup. Could this have skewed my numbers so greatly? Is it because I had to squeeze the bag to get to my boil volume?

George

 

[FLOutlander]

I'm pretty sure the rice extract has something to do with it. Quick question...how in the world did you fit 7 gallons of water AND 11lbs of grain into an 8 gallon pot? How much headspace was left? How full was the pot when you started the boil?

Outlander

 

[Salpino]

Rice syrup has a potential gravity of around 1.045, so definitely a contributing factor. Squeezing the bag helps to get every last gravity point pre-boil. If the bump wasn't due to the rice syrup--which it probably is-- it could be that you boiled off more than estimated. Did you hit your estimated post-boil volume?

 

[Culln5]

I'm pretty sure the rice extract has something to do with it. Quick question...how in the world did you fit 7 gallons of water AND 11lbs of grain into an 8 gallon pot? How much headspace was left? How full was the pot when you started the boil?

Outlander

There was between a quarter to half inch of headspace with the grains and I estimate 6.25 gallons of wort for the boil.

George

 

[Culln5]

Rice syrup has a potential gravity of around 1.045, so definitely a contributing factor. Squeezing the bag helps to get every last gravity point pre-boil. If the bump wasn't due to the rice syrup--which it probably is-- it could be that you boiled off more than estimated. Did you hit your estimated post-boil volume?

The Beersmith numbers included the rice syrup in the recipe. I probably came up a bit short post boil. I was using a 6.5 gallon glass carboy for the first time and it did look light to me. However, I measured the height and turned to HBT to see if someone could convert my height (12.25") to gallons and the formula I found says 5.3 gallons......

George

 

[Culln5]

Rice syrup has a potential gravity of around 1.045, so definitely a contributing factor. Squeezing the bag helps to get every last gravity point pre-boil. If the bump wasn't due to the rice syrup--which it probably is-- it could be that you boiled off more than estimated. Did you hit your estimated post-boil volume?

Do you think I should have added the rice syrup after the mash and measured my OG before the boil? I originally measured the OG before the boil or any additions after the mash.

George

 

[Salpino]

Do you think I should have added the rice syrup after the mash and measured my OG before the boil? I originally measured the OG before the boil or any additions after the mash.



George

George[/QUOTE]


If you plan to brew BIAB with extracts or fermentable syrups, your best bet is to create the recipe, noting the estimated preboil OG, then remove the rice syrup, noting the estimated preboil OG before the syrup. That way you know how many points you need after the mash to hit your numbers and you can control how much syrup to add in order to get spot on.

 

[Culln5]

George

If you plan to brew BIAB with extracts or fermentable syrups, your best bet is to create the recipe, noting the estimated preboil OG, then remove the rice syrup, noting the estimated preboil OG before the syrup. That way you know how many points you need after the mash to hit your numbers and you can control how much syrup to add in order to get spot on.[/QUOTE]

OK....

This is WITHOUT the rice syrup in the recipe:

• Estimated Pre-Boil Gravity - 1.043
• Estimated OG - 1.049
• Estimated FG - 1.009

This is WITH the rice syrup in the recipe:

• Estimated Pre-Boil Gravity - 1.050
• Estimated OG - 1.056
• Estimated FG - 1.011

This is the MEASURED numbers:

• Measured Pre-Boil Gravity - 1.046 (pre rice syrup)
• Measured OG - 1.064 (post rice syrup)
• Measured FG - TBD

So you're saying I should need a PB of 1.043 (without rice) and an OG of 1.056 (with rice)?

George

 

[Salpino]

If you plan to brew BIAB with extracts or fermentable syrups, your best bet is to create the recipe, noting the estimated preboil OG, then remove the rice syrup, noting the estimated preboil OG before the syrup. That way you know how many points you need after the mash to hit your numbers and you can control how much syrup to add in order to get spot on.

OK....

This is WITHOUT the rice syrup in the recipe:

• Estimated Pre-Boil Gravity - 1.043
• Estimated OG - 1.049
• Estimated FG - 1.009

This is WITH the rice syrup in the recipe:

• Estimated Pre-Boil Gravity - 1.050
• Estimated OG - 1.056
• Estimated FG - 1.011

This is the MEASURED numbers:

• Measured Pre-Boil Gravity - 1.046 (pre rice syrup)
• Measured OG - 1.064 (post rice syrup)
• Measured FG - TBD

So you're saying I should need a PB of 1.043 (without rice) and an OG of 1.056 (with rice)?

George[/QUOTE]


Exactly. Without knowing the preboil gravity with the syrup, however, you won't know if the higher OG is due to too much syrup or a higher than expected boil-off rate. To be that close on the preboil without the syrup (3 points) and then that far off on the OG, I have to suspect that either your scale needs calibrating or you boiled off more than beersmith expected.

 

[Culln5]

The Beersmith numbers included the rice syrup in the recipe. I probably came up a bit short post boil. I was using a 6.5 gallon glass carboy for the first time and it did look light to me. However, I measured the height and turned to HBT to see if someone could convert my height (12.25") to gallons and the formula I found says 5.3 gallons......

George

I transfered to a secondary last night and my bottling volume was only 4 gallons. So, I was off by a full gallon somewhere. Maybe I boiled too aggressively...... I did like the taste though!

George

 

[Salpino]

I transfered to a secondary last night and my bottling volume was only 4 gallons. So, I was off by a full gallon somewhere. Maybe I boiled too aggressively...... I did like the taste though!

George

Wildly varying boil-off rates is the toughest part of brewing the same beer over and over with consistent results, and is one of the main reasons I went full electric with my system.

Glad to hear the beer turned out well!

 

[johnodon]

What did you set the "batch size" to in Beersmith?

The average full volume BIAB recipe usually calls for ~8.5 - ~9 gallons of water for a 5.5 gallon batch size. Unless I am reading wrong (or you omitted it), your total water used was only 7 gallons.

Did you top off after the boil/coiling? I'm guessing not.

John

 

[Culln5]

What did you set the "batch size" to in Beersmith?

The average full volume BIAB recipe usually calls for ~8.5 - ~9 gallons of water for a 5.5 gallon batch size. Unless I am reading wrong (or you omitted it), your total water used was only 7 gallons.

Did you top off after the boil/coiling? I'm guessing not.

John

For the 11lb grain bill Beersmith called for 7 gallons of water. After the mash and squeezing the ever loving daylight out it, I estimate that 6.5 gallons was leftover for the boil...... Now, I did have an issue with the flow of wort coming to a stop when I was transferring it through the kettle's 1/2" drain. I have since attributed the shortage to back pressure from the primary being only slightly below the drain and the drain hose being on the bottom of the carboy. Thus I was short transferring. I marked the carboy and filled it with water and I believe I transferred about 4.25 gallons to the primary and lost .25 gallons to trub afterwards.

George

 

[johnodon]

That seems like an awfully low water volume to me. Almost all of my recipes for 5.5 gallon batches call for at least 8.5 gallons of water. Here is my BIAB adaptation of BM's Kona's Fire Rock Pale Ale (11 lbs of grains). It calls for 9 gallons of total water.

It seems that most "squeezers" lose anywhere from .07 - .10 gallons of water per pound of grain. If we take the middle as an average (.085), that means that you lose almost a full 1 gallon of water to grain absorption alone for an 11 lb. grain bill. That brings you down to 6 gallons now. Add on top of that 1 gallon per hour of boil off and you are now down to 5 gallons. Trub...that varies. But you can see how the water volume quickly falls.

I will say this. Since I just started again (and with new equipment), I have yet to dial in my equipment. however, I do remember that the default Beersmith properties for BIAB were pretty close and I did not have to do much adjusting to the equipment profile.

John

 

[notixx]

Hey Guys,
I completed my first BIAB yesterday and here's what took place:

• 8 Gallon Pot
• 11.2lbs of Grains
• Mashed In at 153 with 7 gallons of water
• Mashed for 60 mins at 148 (stirring occasionally)
• Pre-boil gravity was 1.046 (Beersmith estimate was 1.050)
• 60 minute boil
• Hung and squeezed the ever-loving crap out of it

• 
  
  
  
  .... did you boil with the grain bag in the water? and then squeeze after? im confused......

 

[Culln5]

.... did you boil with the grain bag in the water? and then squeeze after? im confused......

No, I just listed it out of order.... I mashed the grains, hoisted, drained, "squoze", then boiled.

George

 

[Culln5]

That seems like an awfully low water volume to me. Almost all of my recipes for 5.5 gallon batches call for at least 8.5 gallons of water. Here is my BIAB adaptation of BM's Kona's Fire Rock Pale Ale (11 lbs of grains). It calls for 9 gallons of total water.

It seems that most "squeezers" lose anywhere from .07 - .10 gallons of water per pound of grain. If we take the middle as an average (.085), that means that you lose almost a full 1 gallon of water to grain absorption alone for an 11 lb. grain bill. That brings you down to 6 gallons now. Add on top of that 1 gallon per hour of boil off and you are now down to 5 gallons. Trub...that varies. But you can see how the water volume quickly falls.

I will say this. Since I just started again (and with new equipment), I have yet to dial in my equipment. however, I do remember that the default Beersmith properties for BIAB were pretty close and I did not have to do much adjusting to the equipment profile.

John

Here's what Beersmith calculated for me....

Mash Schedule: BIAB, Light Body
Total Grain Weight: 11 lbs 3.2 oz
----------------------------
Name Description Step Temperat Step Time
Saccharification Add 27.81 qt of water at 152.8 F 147.9 F 60 min


George

 

[Culln5]

Maybe my equipment profile is off?

Equipment Profile: 8 Gallon BIAB Kettle
Batch Size: 5.25 gal

Mash Tun Volume: 8.00 gal
Mash Tun Weight: 10 lbs
Mash Tun Specific Heat: 0.12
Lauter Tun Deadspace: 0.00 gal

Boil Size: 6.22 gal
Boil Time: 60 min
Evaporation Rate: 8.0 %
Calculate Boil Size: TRUE
Kettle Top Up Water: 0.00 gal
Hop Utilization Adjustment: 100.00 %

Trub/Chiller Loss: 0.25 gal
Cooling Loss: 4.00
Top Up Water into Fermenter: 0.00 gal

Created with BeerSmith 2 - http://www.beersmith.com
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George

 

[JDGator]

cooling loss of 4 seems really high. i checked mine out on BS and i'm at .22gal

 

[johnodon]

Let me grab my equipment profile.

Looks like the big difference between our profiles is the boil off rate and trub loss.

I'm accounting for 1.25 gal/hr (which is 15%). The only way to really know for sure if to conduct a water test. Start with your normal volume of water, take a measurement, bring to a boil, start the timer for 60 mins, flame out, take another measurement. However much you lost in that hour, adjust your equipment profile accordingly.

As far as trub loss, you will have more of this with BIAB. .25 gal seems too low to me. Then again, it really only matters if you are siphoning or just dumping into the fermenter.

Batch Size: 5.50 gal
Mash Volume: 15.00 gal
Boil Volume: 8.17 gal
Mash Tun Weight: 25 lbs
Evaporation Rate: 15.3 %
Mash Tun Specific Heat: 0.12 cal/g-deg C
Boil Time: 60
Mash Tun Deadspace: 0.00 gal
Top-up for Boiler: 0.00 gal
Equip Hop Utilization: 100.00 %
Losses to Trub/Chiller: 1.15 gal
Cooling Loss (%): 4.00
Top up water for Fermenter: 0.00 gal

Notes: Sample Brew-In-A-Bag equipment profile set up for a 50 litre brew pot (diameter of 40cm or 16 inches) using a polyester grain bag to hold the grain. This profile should be used with the BIAB mash profiles available in the BeerSmith mash profiles area. The above assumes loose pellet hops and only clear, chilled wort transferred from the kettle using no trub management techniques. Experienced brewers should adjust 'Loss to Trub and Chiller' and 'Brewhouse Efficiency' accordingly to suit their trub management techniques.
Created with BeerSmith