opinions of full volume mashing?

[Roycebarrow]

looking for info on full volume / no Sparge biab mashes. Yesterday, I brewed the nut case brown ale from jaspers home-brew. I boiled the full 7.5 gallons so that by the end of the boil / trub / and transfer, I would still have 5.5 gallons to throw in the carboy. I mashed in and obviously it is a lot of water for an 8lb grain bill. Instead of 60 minutes, the starch wasn't actually converted until about 80 minutes. Is this typical, or should I just dunk sparge? the estimated gravity was 1.043 - 1.047. mine came out to 1.042, no big loss. just looking to see if anyone else does the same.

 

[brew703]

I brew full volume BIAB and for a typical 5 gal batch (10-11 lbs of grain) I use about 7.5 gal of water. This translates to about 1.050 OG. Lately I've been brewing session ales with an ABV of 5 and under.
You'll have a session ale, which isn't a bad thing.
Use a water calculator to determine the volume, such as https://pricelessbrewing.github.io/BiabCalc/#Advanced.

 

[PADave]

This sounds exactly like my method. How are you determining that conversion was not complete at 60 min? I almost always do 60 min mashes and never had any problem. Some say that with BIAB and a fine crush conversion happens real quick, like 15 min and a full 60 min mash is a waste of time. Did you crush the grains or did they?

 

[Roycebarrow]

Hey PADAVE, I crushed the grains at .020 with my grain mill, I checked periodically with iodaphor and waited until it mixed light/clear as opposed to a very dark brownish color that won't mix. I have had issues in the past with a very grainy/burnt'ish taste, so I was very careful with my method on this one. as I was doing more reading, the majority of information always says 1.5-2qts to each pound of grist.

 

[balrog]

Finer grind for BIAB helps convert faster (less time to soak starches if smaller pieces) so maybe you could grind finer. I see now that @PADave beat me to that one.

I agree with @brew703 about the Priceless calc, it's awesome. Once you dial in your boil off and grain absorption rates, using 2-3 batches, it's always spot on. But the same is true with BeerSmith or any of them.

In specific answer to your question about efficiency, the grind repeatability is key.
I get my grains from Ritebrew, and Neil has a double grind option I use and my batches have never varied for efficiency. Recently I was gifted some grain, typical LHBS grind, and I used it as 1/3 of a batch. I did not expect much eff hit but that batch was 61% instead of 72%. So grind matters.

 

[PADave]

Do you do anything with your water? Sounds like your pH might be out of range. From what I understand that can mess up conversion.

Also, for that small of a grain bill, on my system at least, I would have used closer to 7 gal of water to end up with 5.5 gal. One recent brew I did was pushing the limits of my kettle with 15 lbs of grain and I only started with 7.6 gal of water. Of course your system losses will be different. How much did you end up with in the fermenter?

 

[Roycebarrow]

thanks, I was starting to wonder if this tied back somehow to the weird taste I was having for a couple of batches by not mashing with the 1.5 to 2 qts.

 

[Roycebarrow]

Yeah I use EZwater to calculate adjustments to my strike water to hit mash ph
and I ended with about 5 3/4 gallons in the carboy. again I didn't sparge or squeeze the bag.

I'm going to have to wait until this batch turns out to see if I still get the same taste in it.

 

[soccerdad]

I always prefer full volume mash as it is one of the easy/fast benefits of BIAB. Sometimes a large grain Bill causes me to short the water and I dunk into a gallon or so of water to get to my needed boil volume.

But I far prefer: full volume mash, no sparge, no dunk, no pour over, no squeeze. It's easier and I'm lazy.

If you are hitting your numbers for pre boil gravity and water volume, there is no need to squeeze, dunk, sparge or do a special dance.

In my experience a little finer crush or a 90 minute mash will get your pre boil gravity right where you need it. These days my mash is done in 40 mins (typically) .. Most likely due to the crush of my Victoria mill.

 

[mongoose33]

When I started BIAB I relied on some advice from @Morrey , who suggested dropping my mill gap from .035 to .020. It looks a little narrow to me, but amazingly, I had exactly the same efficiency using BIAB and .020 as I had with traditional mash tun and sparging using .035.

I stir at 15 and again at 30 minutes; if you're not doing that, do it. That helps with conversion. Doing that, I typically would have 90-95 percent of conversion by 30 minutes. I still go the full 60 minutes because I tend to buy @RM-MN 's argument that there are flavor components in the mash that are still coming out after 30 minutes.

I agree with @PADave in asking about the pH of your water. I use EZWater as well, but I'm also checking pH at 15 minutes. Usually EZ water estimates a pH that is around .05-.1 higher than what I measure. For a recent lager EZ water predicted a mash pH of 5.41, but I ended up at a measured 5.33. So when I'm using it I just mentally subtract from the predicted value to what I think I'll end up with. I also use EZWater to check the balances and final amounts of chlorides and sulfates.

**********

A note on crush: recently bought a Monster Mill 3, with three rollers. @Morrey has one too, and he suggested I try a gap of .035 to start. I questioned that, as it's quite a bit larger than the .020 I'd been using with my Barley Crusher. But he was right on the .020, so what the heck! I tried that gap and was shocked to learn that conversion efficiency was, again, the same as before. HOWEVER, it was a slower conversion. At 30 minutes I was only at 1.032 gravity; at 60 minutes, 1.0495. The last time I brewed that beer, using .020, I had exactly the same gravity, 1.0495.

Why was the most recent one slower? Larger particles. I got the same results but IMO, that only will work with stirring partway through, which in my case is at 15 and 30 minutes.

 

[Roycebarrow]

@soccerdad , I too am on the side of minimal or laziness as I usually have 15 other things going on at once when I brew. Thanks for the info

@mongoose33 , I adjusted my grinder to .020 previously, and was wondering if grain may be getting through causing the off taste, but I checked the bag and it looked good to me. I haven't previously messed with water profile too much, but I did on this one. I got my city's water report, as well as sent off to ward labs. I noticed the city report PH was drastically different than what I was seeing on my PH reader that is dead on in calibration. That's why I sent off to the lab as well.

EZwater said estimated 5.5 and mash Ph was 5.61. I checked about every 15 minutes after the first 15 minutes, and at room temperature. These are also the samples I used iodaphor with to check conversion.

as usual I bottle about 6 beers and keg the rest, so if it comes out funky after hanging out for a few months, maybe I can send a bottle to someone and let them try it for a better idea of what is going on. I live in Germany and I don't know anyone else in my area that brews beer, but there are many helpful people here on the forum. I'm hoping it was a mash PH problem. if I am getting 5.61 after the corrections I did, who knows what I was even hitting previously.

Thanks

 

[soccerdad]

Just curious .. what are those ph numbers .. what ward gave you and what your meter says.

 

[soccerdad]

Also - although this started with questions about mash and volume, you keep coming back to "that taste". Is it possible that that taste is more to do with ferm temps and less to do with mash?

 

[Roycebarrow]

@soccerdad My city's water report says 7.74, my meter says 7.91 I saw the difference so I sent off to ward labs but have not gotten a report back from them yet but hopefully this week. ezwater estimated 5.5 and I got 5.61 after adjustments. the water report from the city was from 2016.

im questioning full volume because this is one of my methods in question that many people have said to just use 1.5 to 2 qts per lb. So I was wondering if this was affecting my conversion length, or possibly the tatse of my final product. I also wonder if it could have been from starches not fully converting? Seemed like a good troubleshooting point to throw it out to the forum and get some experienced guys involved. As for temps go, I have a cellar here for ales, and also a chest freezer for lagers which has a temp controller on. temps stay pretty low in my cellar, about 65 or a little lower.

Thoughts?

 

[jpakstis]

I'm fairly slovenly with my volume measurements since most of my beers tend to be in the 1.060's - 1.070's OG range. I usually heat up 8.5 gallons because with my equipment and technique I can get about 6 - 6.5 gallons into the fermenter through my BIAB in a cooler setup.

I also squeeze the crap out of the bag and I notice it has a pretty dramatic effect on my gravity readings. I don't have my notes but I remember it going up close to 7 or 8 points of gravity. I get about 1/2 - 3/4 of a gallon extra from squeezing.

 

[Roycebarrow]

I'm fairly slovenly with my volume measurements since most of my beers tend to be in the 1.060's - 1.070's OG range. I usually heat up 8.5 gallons because with my equipment and technique I can get about 6 - 6.5 gallons into the fermenter through my BIAB in a cooler setup.

I also squeeze the crap out of the bag and I notice it has a pretty dramatic effect on my gravity readings. I don't have my notes but I remember it going up close to 7 or 8 points of gravity. I get about 1/2 - 3/4 of a gallon extra from squeezing.

Yeah I see a lot of guys squeezing their bags like crazy online, I just had a good pre boil volume so didn't mess with it. However, that would be a good experiment to squeeze it and track the change in gravity.

 

[jpakstis]

Yeah I see a lot of guys squeezing their bags like crazy online, I just had a good pre boil volume so didn't mess with it. However, that would be a good experiment to squeeze it and track the change in gravity.

I like to gather up as much wort as I can. I tend to lose a decent amount of wort to hopping (both boil and dry) so I like to give myself some extra volume to make up for it. I had an early batch where I ended up with like 3.5 gallons of final product because I was too lean on the volumes and so I like to overcompensate on the front end these days.

It might be worth it to give it a try sometime and see if its of benefit. I like to do it but I'm also not concerned about clarity. I like to make hazy IPAs so my sloppy technique is a feature not a bug!

The only drawback I have encountered with full volume mash is that it can be difficult to adjust the strike temps, especially if its too low. I BIAB in a cooler so I can't heat up the mash tun itself on a burner. But I'm still refining this area.

 

[balrog]

Well, I believe the concentration of the mash should be uniform or something else is going on. My point is that squeezing should not affect preboil gravity. If your post-mash SG is 1.049, after hoisting the BIABag, then anything dripping from the bag should also be 1.049. If all the starch is soluble and the enzymes have converted it and you've stirred it to be homogeneous, then all the water you drain, pour or squeeze should be the same SG gravity. If it's not homogeneous and squeezing brings higher sugar concentration out, then stirring would be called for. I think of the grain as a sponge, maybe like a sponge with sugar in it. Put that in water and it soaks up water and sugar dissolves and once homogeneous, then all the water in the pot and inside the sponge has same sugar concentration. Osmosis and all that.

 

[wilserbrewer]

With only an 8 lb grain bill, losses to trub and transfer could be substantial.

A benefit of buying grain in bulk rather than kits is that it costs almost nothing to throw another half pound in the grain bill and not worry as much. Cheers

 

[doug293cz]

Well, I believe the concentration of the mash should be uniform or something else is going on. My point is that squeezing should not affect preboil gravity. If your post-mash SG is 1.049, after hoisting the BIABag, then anything dripping from the bag should also be 1.049. If all the starch is soluble and the enzymes have converted it and you've stirred it to be homogeneous, then all the water you drain, pour or squeeze should be the same SG gravity. If it's not homogeneous and squeezing brings higher sugar concentration out, then stirring would be called for. I think of the grain as a sponge, maybe like a sponge with sugar in it. Put that in water and it soaks up water and sugar dissolves and once homogeneous, then all the water in the pot and inside the sponge has same sugar concentration. Osmosis and all that.

100% correct. Thanks for saving me some typing.

Brew on

 

[RM-MN]

Well, I believe the concentration of the mash should be uniform or something else is going on. My point is that squeezing should not affect preboil gravity. If your post-mash SG is 1.049, after hoisting the BIABag, then anything dripping from the bag should also be 1.049. If all the starch is soluble and the enzymes have converted it and you've stirred it to be homogeneous, then all the water you drain, pour or squeeze should be the same SG gravity. If it's not homogeneous and squeezing brings higher sugar concentration out, then stirring would be called for. I think of the grain as a sponge, maybe like a sponge with sugar in it. Put that in water and it soaks up water and sugar dissolves and once homogeneous, then all the water in the pot and inside the sponge has same sugar concentration. Osmosis and all that.

I don't find this to be true. If I take a refractometer sample from the top of the kettle near the end of the mash, I will have a low reading but if I stir it and then immediately sample, the gravity will be quite a bit higher. My though on this is that as the starch is converted to sugar, the sugary wort is denser and settles downward. Given time it might mix in evenly but not immediately. The effect is smaller but similar to adding LME to the wort. It wants to settle to the bottom.

 

[balrog]

Agreed, hence the stirring suggestion.

 

[doug293cz]

I don't find this to be true. If I take a refractometer sample from the top of the kettle near the end of the mash, I will have a low reading but if I stir it and then immediately sample, the gravity will be quite a bit higher. My though on this is that as the starch is converted to sugar, the sugary wort is denser and settles downward. Given time it might mix in evenly but not immediately. The effect is smaller but similar to adding LME to the wort. It wants to settle to the bottom.

The stratification you are talking about has nothing to do with settling. In all but the thickest mashes, and particularly for full volume mashes, there is a layer of liquid above the grain bed. The only way sugar gets up into this liquid layer is by diffusion or agitation (stirring or recirculating.) Thus if you sample wort from the liquid layer, prior to any agitation, it will have lower SG than wort down in the grain bed, where the sugar is actually created.

Brew on

 

[Roycebarrow]

Very informative. I usually stir then take some from the valve, and that is what I check gravity, and conversion with.

 

[RM-MN]

The stratification you are talking about has nothing to do with settling. In all but the thickest mashes, and particularly for full volume mashes, there is a layer of liquid above the grain bed. The only way sugar gets up into this liquid layer is by diffusion or agitation (stirring or recirculating.) Thus if you sample wort from the liquid layer, prior to any agitation, it will have lower SG than wort down in the grain bed, where the sugar is actually created.

Brew on

That would make sense if I had liquid above the grain bed but the last few batches I had trouble getting a sample without grain in it because the grain was right to the surface. I still had a much lower gravity until I stirred.

 

[balrog]

I don't run into the stratification situation as I don't measure until I've hoisted the bag, which isn't until after I've stirred. The downside is that were I to find a low conversion efficiency (hope I got that right) I have already moved on to start the boil and just figure I get what I get, but it's always been fine with only one notable issue with GRIND.

 

[doug293cz]

That would make sense if I had liquid above the grain bed but the last few batches I had trouble getting a sample without grain in it because the grain was right to the surface. I still had a much lower gravity until I stirred.

Hmm, have to think about that. How thick was that mash?

Brew on

 

[jdauria]

1.5 to 2 quarts per pound is not what you want for full volume mash, no sparge, that's for a normal mash and sparge system. I do full mash BIAB and usually I am at 2.77 - 3.5 quarts per lb for BIAB.