What effect does mash-out have for BIAB?

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BetterSense

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Typically I mash at 65 to 70 degrees C for an hour, then I raise the temperature of the mash to 80C before lifting the BIAB and letting it drain, and then I rinse the grains with warm water for a 'sparge'.

My last two brews, I completely forgot the mashout step. What effect does the step have anyway? Will skipping it cause worse attenuation or flavor differences? What do other BIAB brewers typically do?
 
So basically sugar is sticky and no matter how much you sparge or rinse, you'll never get all of it. By mashing out at 170°F, you are getting the water as hot as possible without risking tannin extraction. Higher temps makes the sugars more soluble and less sticky and less likely to leave the pot with your bag. It's a simple step (since you're about to boil anyways) that will get you every last bit of efficiency.
 
It denatures the enzymes so that you don't get further conversion if the liquor cools. If you mash at 155 for some body, but then for some reason let it cool to 140, you may end up with overly-fermentable wort, since the lower-temp enzymes will continue to work. I just read a thread about a guy who massed at 155, split the wort in two, boiled the first batch and it dropped to 1.016 or so, and the second batch dropped to 1.008, since it cooled before he boiled.

The above also applies.
 
I mash out on BIAB. It isn't adding to the process since the grain is already in the kettle and you have to heat to a boil.

I add a few % points to efficiency. For the little extra to no extra work it is worth it. Maybe for peace of mind.
 
Mahout helps efficiency - makes the mash liquid less viscous, which allows a little more sugar to be extracted from the grains. In my experience, this gives ~2-4 points of gravity with BIAB. Definitely worth the effort with BIAB since you already have the grains in the kettle!
 
I've been surprised at how watery my latest brews have been coming out. Typically I pull the bag out and rinse the grains with 80C water as a "sparge" step, but the last few brews I have just been using room-temperature tap water to save heating the sparge water on the stove. Since I also didn't mash out, and my wort has been cooled by the cooler "sparge" water, this could definitely be responsible for my thin body.
 
Up until about 10-12 brews ago, I was a dedicated full-volume-mash with mash-out BIABer and I was getting 80% efficiency on a consistent basis. Then I switched from 4 gallon to 5 gallon batches and my 8 gallon BK was a little undersized for a lot of my recipes, so I started mashing a gallon short and doing a 1 gallon sparge (pouring 168°-ish sparge water over the grains). I continued to do the mash-out, but simply adding the sparge step resulted in a consistent gain of 5+ OG points. I have read several posts where BIABers have stated that they don't do a mash-out and still get 85%, which is where I was after doing a sparge. That got me thinking that maybe the M/O is not really necessary.

So, last weekend I brewed a 1.050 Vienna lager, did a 2 gallon sparge with no mashout and still overshot my OG by 3 points, even though my recipe was based on 85%. My conclusion, for BIAB, when doing a sparge, mash-out is unnecessary where OG is concerned. If not doing a sparge, M/O may be necessary to get those last few points, but I can't state for sure, as I've not compared the results of doing a full-volume mash with and w/o the mash-out.
 
Up until about 10-12 brews ago, I was a dedicated full-volume-mash with mash-out BIABer and I was getting 80% efficiency on a consistent basis. Then I switched from 4 gallon to 5 gallon batches and my 8 gallon BK was a little undersized for a lot of my recipes, so I started mashing a gallon short and doing a 1 gallon sparge (pouring 168°-ish sparge water over the grains). I continued to do the mash-out, but simply adding the sparge step resulted in a consistent gain of 5+ OG points. I have read several posts where BIABers have stated that they don't do a mash-out and still get 85%, which is where I was after doing a sparge. That got me thinking that maybe the M/O is not really necessary.

So, last weekend I brewed a 1.050 Vienna lager, did a 2 gallon sparge with no mashout and still overshot my OG by 3 points, even though my recipe was based on 85%. My conclusion, for BIAB, when doing a sparge, mash-out is unnecessary where OG is concerned. If not doing a sparge, M/O may be necessary to get those last few points, but I can't state for sure, as I've not compared the results of doing a full-volume mash with and w/o the mash-out.

Try doing your sparge step with cold water and see what results you get. I do no mash out and sparge with cold water. I set the software for 80% efficiency and usually overshoot the intended OG.
 
Try doing your sparge step with cold water and see what results you get. I do no mash out and sparge with cold water. I set the software for 80% efficiency and usually overshoot the intended OG.

I'm thinking I may give that a try next time.

Update: Brewed an Octoberfest yesterday. At RM-MN's suggestion, decided to try the sparge (went with 2 gallons due to mash volume limitations) with room temp filtered water. Result: 86% efficiency.
 
I'm thinking I may give that a try next time.

Update: Brewed an Octoberfest yesterday. At RM-MN's suggestion, decided to try the sparge (went with 2 gallons due to mash volume limitations) with room temp filtered water. Result: 86% efficiency.

Yes agreed! Mashout IMHO is not needed, and a cold sparge will work!
 
Yes agreed! Mashout IMHO is not needed, and a cold sparge will work!

I will second that. Yesterday I did no mashout and the sparge water was whatever the temp that comes out of the faucet when on cold( guessing mid 60s). Got 85% efficiency.
 
so, let me get this straight...no mash out @ 170 degrees, but a cold water sparge?? If 2 gal sparge, then mash volume is 2 gal less?
Do you put the bag in strainer over bucket to sparge? Then squeeze bag, too??
Thanks

I've been averaging 65-68% efficiency with mash out.
 
so, let me get this straight...no mash out @ 170 degrees, but a cold water sparge?? If 2 gal sparge, then mash volume is 2 gal less?
Do you put the bag in strainer over bucket to sparge? Then squeeze bag, too??
Thanks

I've been averaging 65-68% efficiency with mash out.

Sparge with whatever temp you want, keep in mind though that the warmer you sparge the quicker you get up to boiling, shortening your brew day. Yes, dunk the grain in sparge water then stir, pull, squeeze/press, or pour water over the grains then squeeze/press.
 
Sparge with whatever temp you want, keep in mind though that the warmer you sparge the quicker you get up to boiling, shortening your brew day. Yes, dunk the grain in sparge water then stir, pull, squeeze/press, or pour water over the grains then squeeze/press.

That is a good point and probably why it took so long for my beer yesterday to come up to a boil:smack:
 
If I leave out 2 gal of water from my mash (for sparging later), will having less water in my mash (having a thicker mash) affect the mash?
 
The folks over at BIABrewer.info have used scientific method and data to show that the best scenario is to do a "true" BIAB where you mash with the total water volume and do not sparge at all. They claim that the belief that sparging will increase efficiency by rinsing more sugars from the grain bag is false.
I am not an expert in this area so don't ask me to explain it. If you're interested then check out their site. I believe some of their members were involved in the beginning stages of this process.

I don't always understand what they say ,but I follow it and always get great efficiency.
 
If I leave out 2 gal of water from my mash (for sparging later), will having less water in my mash (having a thicker mash) affect the mash?

As mentioned above, it will affect your efficiency that you may get back from sparging.
I'd also recommend sparging with hot water to increase efficiency and shorten the brew day.
 
The folks over at BIABrewer.info have used scientific method and data to show that the best scenario is to do a "true" BIAB where you mash with the total water volume and do not sparge at all. They claim that the belief that sparging will increase efficiency by rinsing more sugars from the grain bag is false.
I am not an expert in this area so don't ask me to explain it. If you're interested then check out their site. I believe some of their members were involved in the beginning stages of this process.

I don't always understand what they say ,but I follow it and always get great efficiency.

I'd disagree with them. When I squeeze out the bag of grains the bag is really sticky. That stickiness is caused by the sugars that remain. When I do a small (2 qts or so) sparge I gain 5 to 10% in efficiency because I can dissolve those sugars with the sparge water and capture them in my wort instead of throwing that much sugar away.:rockin:
 
I'd disagree with them. When I squeeze out the bag of grains the bag is really sticky. That stickiness is caused by the sugars that remain. When I do a small (2 qts or so) sparge I gain 5 to 10% in efficiency because I can dissolve those sugars with the sparge water and capture them in my wort instead of throwing that much sugar away.:rockin:

Again, I don't claim to know the full explanation. However, I believe the premise is if you don't use all the water in the mash, then the mash you produce is more concentrated with sugar so less will diffuse out of the bag. You would then need to sparge to get more of that sticky sugar out of the bag (as you said). If you use all the water, then you have a more dilute mash and there is a greater tendency for more of the sugar to leave the bag while the mash is occurring and then there is less need for sparging. That being said, even though I don't sparge, I do squeeze the bag to get more wort out of it and add that back to the kettle. That step will increase the amount of beer you eventually produce.
 
I'd disagree with them. When I squeeze out the bag of grains the bag is really sticky. That stickiness is caused by the sugars that remain. When I do a small (2 qts or so) sparge I gain 5 to 10% in efficiency because I can dissolve those sugars with the sparge water and capture them in my wort instead of throwing that much sugar away.:rockin:

Same here. I've done it both ways (approx. 20 batches at full boil volume and at least 10 with a sparge) and there's definitely at least a 5 point increase when a sparge is utilized. To the point that I've had to up my default efficiency setting in BeerSmith to 85% from 80%, and I've never missed to the low side since incorporating a sparge. That wasn't the case when I was mashing with the full boil volume and not sparging.
 
This is interesting...how much of the full volume do you reserve for the sparge, and specifically how do you sparge? Dunk, or sprinkle water over / thru the bag?
 
This is interesting...how much of the full volume do you reserve for the sparge, and specifically how do you sparge? Dunk, or sprinkle water over / thru the bag?

I reserve two gallons for the sparge and pour it over the grains. The sparge water comes right out of my fridge water dispenser with no heating.
 
This is interesting...how much of the full volume do you reserve for the sparge, and specifically how do you sparge? Dunk, or sprinkle water over / thru the bag?

I only use a couple of quarts and it comes straight from my cold water tap. I'll have the grain bag sitting in a colander which is sitting in a plastic bowl. I open the top of the bag, run the water in, stir the grains so the water is dispersed, then squeeze it back out.
 
Same here. I've done it both ways (approx. 20 batches at full boil volume and at least 10 with a sparge) and there's definitely at least a 5 point increase when a sparge is utilized. To the point that I've had to up my default efficiency setting in BeerSmith to 85% from 80%, and I've never missed to the low side since incorporating a sparge. That wasn't the case when I was mashing with the full boil volume and not sparging.

Only logical conclusion is that sugar falls out of the bag in Australia, and goes the same direction in the Northern hemisphere...hence the grains need a rinse! :cross: haha

Thanks for sharing your your experience I'm going to try rinsing my grains next time. I've only brewed one AG BIAB batch (my first AG brew) but got somewhere in the range of 75-80% efficiency. (Full volume mash)

Issue I ran into after mashing was that even 15 mins later I could NOT squeeze the grains very long without burning my dang hands! I can see rinsing with cold water being a TREMENDOUS help in that department! :D

Quite honestly, it just makes sense that if you pull a bag of grain out of sticky, sugary water, some sugar will be stuck to the grain. Therefore, if you rinse it off, you will capture more of the sugar! :)

The case being that folks can already get 75-85% efficiency without sparging - they can decide if it's worth it...

For me I only have a 10.5 gallon pot, and once I go to brew some stronger beers, I plan on mashing with as much water as I can fit, and then rinsing my grains to get a few more OG points! :mug:

I was thinking about laying a new clean Weber Grill grate across the top of my kettle to set the grain bag on and sparge through, then press the grains against. The plastic colander I have isn't quite big enough! Any other thoughts on what to set the grain bag on?
 
I was thinking about laying a new clean Weber Grill grate across the top of my kettle to set the grain bag on and sparge through, then press the grains against. The plastic colander I have isn't quite big enough! Any other thoughts on what to set the grain bag on?

You could rig a simple pulley and rope to hoist out the bag. Tie down the other end of the rope to suspend the bag just above the wort.
 
No sparge here and get 75-85% depending on the size of the brew. Smaller beers get the higher efficiency. I guess I could try a sparge but figure a few extra points isn't really worth the extra step to me.

I also do a mash out since I have to bring it up to boil anyways so why not just leave the grains in there while bring up the heat.
 
No sparge here and get 75-85% depending on the size of the brew. Smaller beers get the higher efficiency. I guess I could try a sparge but figure a few extra points isn't really worth the extra step to me.

I also do a mash out since I have to bring it up to boil anyways so why not just leave the grains in there while bring up the heat.

Do you stop @ 170 and hold for 10 minutes?
 
You could rig a simple pulley and rope to hoist out the bag. Tie down the other end of the rope to suspend the bag just above the wort.

I will probably need to do that for bigger beers just to support their weight.

I don't have a basket though (wouldn't fit well with my brewmometer anyhow) and not sure how I could rinse the grains if they are suspended in a bag? Do you do that? Just pour water over the outside of the bag? Can't picture if it would work?

:confused:
 
Yes, I now use a basket, but you could just tie the end of the rope around the top of the bag and hoist. I would think you could pour the sparge water over the top of bag, being careful to not let it run down the outside of the bag. The basket does help keep the grain flatter than in a bag alone and makes my pour-over sparge easier. My pot has a brewmometer too (2" probe) so I had to find a basket that was small enough in diameter to not hit it.
 
Good deal, sounds like it might be a good way for me to go.

Do you press down pretty hard on your basket with it tied off? I suppose if everything I use is sturdy enough it should be fine, but I'm a bit leery about it.
 
I basically took the whole idea from Seven's BIAB sticky. Seven's process is no-sparge, but it is easy to do a pour-over with this system. After sparging, I push down on the grain with a smaller pot lid to squeeze out a little more wort. The rope I use is just some 5/16" nylon I got at Lowe's. I think it has a break strength of over 100 lbs, so I'm not worried about breakage. The pulley is mounted with an eye bolt into a rafter in my garage. I tie the other end of the rope to an eye bolt in a stud in the garage wall.
 
I was thinking about laying a new clean Weber Grill grate across the top of my kettle to set the grain bag on and sparge through

I did this and had mixed results. 1) I guess my patio isn't totally level and when the drip slowed down it would run down the length of the grill to the edge of the BK and drip over the side (the grill was larger diameter than my BK). 2) Most of them (even "stainless" ones) have some sort of packing grease or something else that typically burns off but I couldn't really get it all off with soap and water even though I put in a lot of elbow grease. 3) after one use my "stainless" grate had surface rust even though I dried it. YMMV but I probably won't use it again.
 
doomXsaloon said:
Do you stop @ 170 and hold for 10 minutes?

No, I just bring it up to 170, pull my basket, set a grill rack over the kettle to set the basket on then squeeze the grains.
 
Do any of you guys that sparge treat you sparge water? I thought pouring regular tap water with a PH over 6 can cause tannin extraction?
 
I don't. Others can correct me if I'm wrong, but I believe as long as the runnings coming out of the sparge are >1.010, the grain should still be effective at keeping the pH down.
 
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