Mash out and BIAB

Michael_biab

Michael_biab

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Is a mash out (raising mash to 168 deg F or 170 deg F) really necessary when brewing via BIAB technique (Brew In a Bag)? I worry about the risk of burning my bag after having read others with this problem since the bottom of the pot is getting way hotter than that. It's also another process step I'd rather avoid to streamline the brew day if possible.
 
I use 170° sparge water instead of raising the kettle temp. I pull my bag and put it in a 6.5 gallon bucket on top of an upside colander (as a false bottom) to drain. That’s where I sparge.
 
I have done it both ways using BIAB. I haven't really found a difference either way. I settled on just leaving my bag in while I heat up to my boil temp and pull it out and let it drain when I get to around 175. I have a false bottom though so I don't have to worry about the element.

If you can't safely keep the bag from getting burned I would skip the mashout.
 
What Jeff said works great.
You can also turn on your burner to a low setting around 45 minutes in and just give it a gentle stir every couple of minute until you get to you 60 minute mark.
Many ways to skin a cat!
Cheers,
Brian
 
Michael_biab said:
raising mash to 168 deg F or 170 deg F
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There's no reason for that type of mashout step with BIAB. Mashout is to rinse the grains of residual sugar which you can't do with wort that's already in equal solution. It's like trying to chill 200° water using 200° cooling water.

To extract that sugar you have to sparge with a liquid devoid of sugar. 170° is only because sugars are more soluble in hot water, but over 170 risks tannin extraction. With typical sparging, water is in contact with the grain bed for such a short time that temperature doesn't really matter to efficiency.

My process evolved to dunk sparging in a separate pot of room temperature water while the mash was heating up to boil. Before developing that approach, I would set the bag in a colander over the pot and pour water over it. More often than not the colander made a mess. Especially with wheat or rye, or if my sparge water calculations were off.
 
Mashing out also helps to lock in the profile you were targeting. It does thin the sugars a bit but not significantly.
 
The Brew Mentor said:
Mashing out also helps to lock in the profile you were targeting. It does thin the sugars a bit but not significantly.
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It also improves extract efficiency and can increase the amount of dextrin extracted for head retention and mouthfeel. Alpha amylose enzymes are active up to 168F but denature in about 10 minutes at that temp.
 
The Brew Mentor said:
Mashing out also helps to lock in the profile you were targeting
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Enzyme activity is stopped whenever the temperature is raised. In 3 tier systems it helps to heat before lautering and 170 is critical for that. There's no lauter transfer in biab, so it can start heating to boil immediately after grains are pulled. No rest is needed.

Cool water dunk is also effective here, dropping the sparged wort below the peak enzymatic ranges without risking tannins. This can then be boiled separately (smaller vol. heats quickly) or added back to the main wort near boil. You can do a dunk infusion to 170 if you remember to heat the sparge pot ahead of time. It requires better calcs and temp control.
 
Michael_biab said:
Is a mash out (raising mash to 168 deg F or 170 deg F) really necessary when brewing via BIAB technique (Brew In a Bag)? I worry about the risk of burning my bag after having read others with this problem since the bottom of the pot is getting way hotter than that. It's also another process step I'd rather avoid to streamline the brew day if possible.
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Quick answer, no. From your description, you're doing no-sparge? As soon as you heat the boil up past a certain temperature, the enzyme activity stops and you're not too worried about loosening up any sugars in the spent grain so mash-out seems unnecessary to me.
 
Ive been employing a mash out step to nearly all my brews for one sole reason increased efficiency and i think a better sparge. I get both the grain and sparge water to the same ish temp 75c to rinse the sugars off the grains. Weather or not this helps in the sparge is still contentious but if i sparge with cool water im slowing down my boil time so why not sparge hot it seems right. think of honey or your maltose syrup back in the kit days. You heat up your can of malt to help it run better well same applies to them trapped sugars in the grain bag heat them up and get them running!

At a steady 80% BIAB efficiency im happy whith this method:).
 
Trialben said:
Ive been employing a mash out step to nearly all my brews for one sole reason increased efficiency and i think a better sparge. I get both the grain and sparge water to the same ish temp 75c to rinse the sugars off the grains. Weather or not this helps in the sparge is still contentious but if i sparge with cool water im slowing down my boil time so why not sparge hot it seems right. think of honey or your maltose syrup back in the kit days. You heat up your can of malt to help it run better well same applies to them trapped sugars in the grain bag heat them up and get them running!

At a steady 80% BIAB efficiency im happy whith this method:).
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I agree. I get anywhere from the low 80’s to the low 90’s% effiencies. Most time it’s at 85%. Without a mash out, I couldn’t hit those numbers. If you watch your gravity before and after a mashout, it rises 15-20%. Your extracting and converting the sugars that the beta enzyme just couldn’t and the alpha could. I think it makes for better beer.

You don’t have to mashout, but if you can without scorching, there are some advantages.
 
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jeffpn said:
I use 170° sparge water instead of raising the kettle temp. I pull my bag and put it in a 6.5 gallon bucket on top of an upside colander (as a false bottom) to drain. That’s where I sparge.
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My preferred method also.
Another way to bring up efficiency is to double miil your grains for BIAB.
 
Medarius said:
My preferred method also.
Another way to bring up efficiency is to double miil your grains for BIAB.
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The 170 degree sparge works just as well as a mash out. I don't worry about it too much, the enzymes denature over time at mash temperature anyway.
 
To respond to Nosybear, no I have not been sparging with my BIAB, just squeezing the bag and going straight to boil. From the responses, it looks like a lot of you are sparging and maybe that would help me with efficiency and perhaps improve the beer if I'm following the thread correctly. Maybe I will try a sparge this weekend with the barleywine I'm planning to brew. Thanks everyone for your thoughts!
 
I shoot for a mash out volume of 2 gallons less than my preboil volume. I dump a gallon at a time twice through the grains. That usually gets me around 75%, squeezing the grains a bit, too.
 
jeffpn said:
That usually gets me around 75%, squeezing the grains a bit, too.
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squeezing the grains a bit? Didn't I hear you say in a previous post that you squeeze it like it owes you money or something like that?:eek: lol. I'm still stuck around 73% efficiency, so who am I to say.:D
 
No, I don’t think I said that. But I’m not opposed to it!
 
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