Not hitting OG with BIAB system

[Ward Chillington]

Maybe I missed it but.....what kinda numbers are we talking about here? Target OG?? Actual OG? And are you doing 1/2 batches? You said you had only one 5 gallon and a 10 gallon electric system.

 

[Sandy Feet]

For $30, get a refractometer. You only need a drop. I have always done BIAB and that is how I do it. I take a 50ml beaker. Get a sample. Let it cool and settle a little. Then take a pipette and get a clear sample

I just broke down and ordered one on Amazon. It was only $19, and I get it tomorrow.

 

[Minbari]

I just broke down and ordered one on Amazon. It was only $19, and I get it tomorrow.

For what they cost. Makes life so much easier. Just remember, if you use it post fermentation. You have to correct for the alcohol.

 

[soccerdad]

Most things I do I have to correct for alcohol.

 

[jmcnamara]

Most things I do I have to correct for alcohol.

You just have to be the monkey in charge of the bananas!

 

[Daniel Parshley]

Forgive me for not being here in a long time. I pretty much quit drinking so I brew way way less. I have some catching up to do. Coronajax - when you say not hitting OG, do you mean that your pre boil gravity is low? That you are not getting as much from the mash as you thought? If that is the case, let the mash go another 30 minutes. The folks in OZ who pretty much pioneered BIAB always said to mash for 90 minutes to assure full saturation of the grain. If you ARE hitting the pre boil gravity but coming short at the end of the boil, then it might be that you are boiling off less than your software calculated that you would.

I usually have more volume than calculated, and sometime way more volume. My guess is the 80-80% humidity and scorching heat (high due point) has a lot to do with it.

 

[GFHomebrew]

Most things I do I have to correct for alcohol.

!
Thanks for that lol

 

[Bay Brewing]

I had the same problem with my Clawhammer. I set my mill to it's finest adjustment ~.28 and my efficiency climbed to up over 70%. I also push the heck out of the grains when draining the basket. I use a 1 gallon pitcher and press down on the grains.

 

[Brewer #300724]

I do BIAB and recently have done a couple things to boost my efficiency.
Here are the things I've done:

• Double crush grains - I always have my LHBS do this
• stir every 15 mins - I've always done this
• When stirring, lift the bag out (only for a minute or two), let it drain a little and put it back in before stirring
• I have begun mashing more that 1 hour - this was the biggest change. I used to use the iodine test and after an hour it would be a little brown but not black. By chance during a brew session I had to let the mash sit for a few hours. My OG was boosted by quite a bit. The next brew I did I mashed for 2 hours and again my OG was boosted. I haven't found the sweet spot yet but the increased mash time has made a big difference.

I'm just doing a basic BIABag in an electric kettle. It's not an all in one or BIABasket.

 

[Herm brews]

I do stove top BIAB, and until recently was regularly hitting or exceeding my recipe projected OG and abv. However, the last several batches, my extraction and brewhouse efficiency has suffered, while my pre and post boil gravities have been well below projections. The decreases occurred before I moved from Southern California to Eugene, Oregon. The brewhouse efficiency of 80% that served me well in the past needs adjusting, which in turn will affect my process - at least if I want to achieve the results that I’m looking for.
Before moving, my grains were crushed by the lhbs (Windsor) where I bought my grains, and they used a mill that apparently had a setting for BIAB. Prior to using Windsor,another lhbs allowed customers to mill their own, and there I always ran the grains through twice. In both cases, there was a good amount of flour in the milled grains.
Now in Eugene, I bought my own mill and have continued double milling, with the rollers set to “credit card” width. Both of the batches I have brewed here have been disappointing in the aspect of low OG and efficiency. I know I could add DME or other tricks, but I just want to get back to how my batches were before, without any tricks.
I’ll be following this thread.

 

[Pricelessbrewing]

I usually have more volume than calculated, and sometime way more volume. My guess is the 80-80% humidity and scorching heat (high due point) has a lot to do with it.

Humidity can definitely affect your boil off rate a bit, but it shouldn't have a huge impact, maybe a quarter gallon or so?

 

[Brewer #300724]

I do stove top BIAB, and until recently was regularly hitting or exceeding my recipe projected OG and abv. However, the last several batches, my extraction and brewhouse efficiency has suffered, while my pre and post boil gravities have been well below projections. The decreases occurred before I moved from Southern California to Eugene, Oregon. The brewhouse efficiency of 80% that served me well in the past needs adjusting, which in turn will affect my process - at least if I want to achieve the results that I’m looking for.
Before moving, my grains were crushed by the lhbs (Windsor) where I bought my grains, and they used a mill that apparently had a setting for BIAB. Prior to using Windsor,another lhbs allowed customers to mill their own, and there I always ran the grains through twice. In both cases, there was a good amount of flour in the milled grains.
Now in Eugene, I bought my own mill and have continued double milling, with the rollers set to “credit card” width. Both of the batches I have brewed here have been disappointing in the aspect of low OG and efficiency. I know I could add DME or other tricks, but I just want to get back to how my batches were before, without any tricks.
I’ll be following this thread.

Weird that it would just change with no change in the process. I'm nowhere near 80% But this recent jump probably went from the mid 60s to the mid 70s.

 

[Zambi]

I can't really see why @Herm brews , but could your water have an impact?

 

[Sunfire96]

I do stove top BIAB, and until recently was regularly hitting or exceeding my recipe projected OG and abv. However, the last several batches, my extraction and brewhouse efficiency has suffered, while my pre and post boil gravities have been well below projections. The decreases occurred before I moved from Southern California to Eugene, Oregon. The brewhouse efficiency of 80% that served me well in the past needs adjusting, which in turn will affect my process - at least if I want to achieve the results that I’m looking for.
Before moving, my grains were crushed by the lhbs (Windsor) where I bought my grains, and they used a mill that apparently had a setting for BIAB. Prior to using Windsor,another lhbs allowed customers to mill their own, and there I always ran the grains through twice. In both cases, there was a good amount of flour in the milled grains.
Now in Eugene, I bought my own mill and have continued double milling, with the rollers set to “credit card” width. Both of the batches I have brewed here have been disappointing in the aspect of low OG and efficiency. I know I could add DME or other tricks, but I just want to get back to how my batches were before, without any tricks.
I’ll be following this thread.

If I were you I'd change the mill gap setting. Make it as small as you can while still being able to turn grain through it. Extract efficiency in BIAB is almost always because of the grain crush.

 

[Megary]

If I were you I'd change the mill gap setting. Make it as small as you can while still being able to turn grain through it. Extract efficiency in BIAB is almost always because of the grain crush.

I agree with this. The three biggest movers of BIAB efficiency for me have been, in order:

1. Crush - for BIAB, a finer, floury crush jacked up my extraction. Crush 'til you're scared as they say.
2. Mash water:grain ratio. The bigger that number, the better the extraction. In other words, for a full volume mash, smaller gravity beers lead to easier/better extraction, bigger beers the opposite.
3. Mash Time - I get better extraction from mashing for 90 minutes vs 60, or 60 vs 30.

Mash temp, Mash pH, grain bill etc. also move the needle, but FOR ME, the above 3 are the biggest players in sugar extraction.

 

[Herm brews]

I can't really see why @Herm brews , but could your water have an impact?

I’m using my own tap water now in Eugene, and it is of excellent quality. I have used brewing salts - maybe I should try a batch of unseasoned water. Not sure that would have any impact on efficiencies, but it might provide a data point.

 

[Herm brews]

I agree with this. The three biggest movers of BIAB efficiency for me have been, in order:

1. Crush - for BIAB, a finer, floury crush jacked up my extraction. Crush 'til you're scared as they say.
2. Mash water:grain ratio. The bigger that number, the better the extraction. In other words, for a full volume mash, smaller gravity beers lead to easier/better extraction, bigger beers the opposite.
3. Mash Time - I get better extraction from mashing for 90 minutes vs 60, or 60 vs 30.

Mash temp, Mash pH, grain bill etc. also move the needle, but FOR ME, the above 3 are the biggest players in sugar extraction.

As for crush, I’m running the grains through the mill twice, and getting plenty of flour. Working harder, cranking the mill by hand, just ‘cuz I enjoy the exercise. I could adjust for tighter gap, maybe only have to run grains through once?
As for water, I’m doing full volume mash, using amount dictated by recipe builder on this site. The mash seems not thick in the least, but maybe I could add a bit more.
I have always mashed for 60+ minutes, and Monday’s batch went 20+ minutes longer to accommodate lunch without positive effect. Usually, I mash around 152F-154F, dropping to ~148F-150F after an hour.
As for mash pH, I try to be in that 5.2-5.6 range.
Thanks for the input.

 

[Sunfire96]

As for crush, I’m running the grains through the mill twice, and getting plenty of flour. Working harder, cranking the mill by hand, just ‘cuz I enjoy the exercise. I could adjust for tighter gap, maybe only have to run grains through once?
As for water, I’m doing full volume mash, using amount dictated by recipe builder on this site. The mash seems not thick in the least, but maybe I could add a bit more.
I have always mashed for 60+ minutes, and Monday’s batch went 20+ minutes longer to accommodate lunch without positive effect. Usually, I mash around 152F-154F, dropping to ~148F-150F after an hour.
As for mash pH, I try to be in that 5.2-5.6 range.
Thanks for the input.

You shouldn't need to run them through twice with your own mill, just set the gap smaller. Double milling is for mills that are set for traditional mash vessels but you want to utilize BIAB and they cant/won't change the gap setting.

Adding a batch sparge or rinse would certainly increase your yield, but at the expense of decrease to simplicity/more vessels to clean.

I doubt pH or brewing salts are giving you the large decrease you're seeing.

The best extract efficiency I got was milling my own grain as small as possible and adding a batch sparge

 

[Herm brews]

You shouldn't need to run them through twice with your own mill, just set the gap smaller. Double milling is for mills that are set for traditional mash vessels but you want to utilize BIAB and they cant/won't change the gap setting.

Adding a batch sparge or rinse would certainly increase your yield, but at the expense of decrease to simplicity/more vessels to clean.

I doubt pH or brewing salts are giving you the large decrease you're seeing.

The best extract efficiency I got was milling my own grain as small as possible and adding a batch sparge

Your suggestions seem sound, so I’ll give both of these things a try. I already use and have to clean multiple vessels, so why not heat extra water for a sparge?
Just to try it, I’m gonna use unseasoned tap for my next brew - great water here!

 

[Zambi]

I mill twice as for some reason the mill doesnt run nicely if I make the gap smaller. I also mill by hand like @Herm brews.
I found quite a big difference by mashing longer. 3-4 hours or so. I found this out by accident. Something came up during mash and I had to let the wort sit longer than intended.
I sparge. A little
No extra things to clean as I use the bowl that had my crushed grains. I drain grains as much as possible in colander over pot with wort by pushing the bag.
Then bag goes to bowl. Add water, stir, squeeze. Liquid goes to pot, bag goes to colander. Repeat.
Unknown volume but I know I'll overshoot SG as I know volume of pot. Final correction of SG is with cold water when transferring to fermenter. It helps cooling.
I realise this is only possible because I do small batches, but so does Herm