Biab Process Inconsistency

[GuyQLD]

Morning all,

About 5 batches in so far and I can't begin to describe how frustrating it's been trying to get my gear dialled in. I've been crunching some numbers in excel as well as googling a fair bit but with so much of BIAB information being based on the individual and their gear, consistent answers are hard to come by and most responses come with a "YMMV".

I've missed my strike temp on all 5 batches, either ending up too low or too high (mostly too high). I'm using the calculator in Brewmate (And I have an excel version I made up as well to check my figures) but somehow I keep missing.

I've been keeping a digital thermometer on hand as it approaches strike temp, gas off then in with the grain but I think I might be rushing it here; example my last brew I had a strike temp of 69 degrees, gas off, mashed in and looking good. Lid on, sleeping bag over the lot and walked away. Checked it at about 45 mins for temp loss and I got a reading of 71 degrees.

I can only think that because I'm monitoring it as it approaches temp I may not be getting a consistent temp through all the liquid, only solution I can think of is when I get close stir the buggery out of it to ensure that it's the same temp throughout and maybe flame out for 5 minutes or so while stirring. Might have to go a bit higher this way, but I can always let it drop to strike temp before I mash in.

Sound good?

Right, onto the hard stuff.

I've probably shot myself in the foot a bit here because I've been changing my process a little each time and so haven't been able to establish a baseline but this next part relates to mashout/sparging.

I'm using a 37L crab cooker from BCF and I've made the following assumptions based on the last few attempts

Trub loss: 1-2L (Apparently whirl pooling is something I can do)
Boil off: Depending on the boil - between 4-6L per hour
Water loss to grain absorption: I'm using 0.7L as a start because I haven't yet measured it. I probably really need to.

Now there's many ways to skin a cat and it all depends on what you're trying to accomplish.

The first thing I need to establish is mash out; How important is it? And is it's importance mainly around liquifying the mash for better drainage? (since locking enzymatic conversion isn't really a factor with BIAB from what I understand)

I've pretty much narrowed down to three possible scenarios with my gear.

1- The full volume no sparge; It's going to be a tight fit though based on the above assumptions, we're talking about a litre of headspace during mash. Once the grain comes out though it drops to a manageable level. If a mashout is needed, I'm assuming turning the gas back on is the only option with this method. With my 3 ring burner that's about a 12-15 minute job and I'd be worried that's too slow.

2- Dunk Sparging; I've done this on most of my brews and I'll be honest it's a PITA with my gear. I'm probably the most ghetto brewer out there (My brew stand is two bricks and the only "bucket" I have for dunk sparging is a spare 23L esky). But it suits my sizes as I can mash with about 24/25 litres and then dunk sparge into another 8/9 litres bring me up to a pretty hefty starting volume. As for being worth it, well I just don't know.

3- Adding sparge water; Mash with 24/25 litres then dump in 8 litres of boiling water brings me back up to the brim at 78'C or there abouts.

Perhaps I'm trying too hard and I need to put the brakes on, go back to no sparge full voume with no mashout and work on my consistency first. It's not like I haven't been getting at least 70% efficiency (most cases 75-78%.... only the one beer I did with pilsner malt dropped to 70%)

Any tips out there? Or anyone have a rough idea of just how much difference any of this makes? If it's only going to be 3-5%, then maybe I should go back to basics until I can start getting consistent results.

 

[beerdrinkingbob]

Hi mate,

Sounds to me like there is residual heat in the pot etc, just stir it round and check in a couple of minutes, if it's still ok then mash in.. When you mash in give it a good stir for about three minutes and measure the mash temp again before you put the sleeping bag on, if it's still too high then keep stirring and it will come down over a couple of minutes.

I loss about 4 litres to trub but I use around 8.5 kg for a double BIAB keggle batch. I also do a single dunk sparge to grab an extra point or two, but mostly to create the space in the vessel so I don't have to push the limits like yourself.

Mash out is important in BIAB for efficiency reasons, thins the liquor and helps the sugar escape, but it also has the other benefits as you have pointed out.

Hope that makes sense, i have the man flu so the head isn't as on the ball.

Cheers

BDB

 

[Phoney]

G'day Guy,

beerdrinkingbob is on the money with the mash in. After you've dumped your grain, keep stirring for a good 5 minutes. This will not only ensure that you have smashed up all of the little dough balls, but you'll also be sure that your temperature is spot on before you doonah up your pot.

I havent used brewmate, but beersmith 2 has functions where you enter in your equipment and it will calculate your start volumes and strike temperature for you. I find this to be accurate enough 95% of the time.

Mash out: Important enough for you to bother with it. It serves two functions; It locks in the enzymes to stop prevent further changes to your starch conversions (Thirsty Boy has written a two page essay going into to the technicalities of this before, but this is basically what I got out of it and it's good enough for me) and secondly like heating up honey it makes the sweet stuff runnier so that your sugars will drain easier. You say it takes 12 - 15 mins to reach mashout temperature from the end of your mash? No problem. With an electric element it takes even longer than that. Just keep gently stirring the entire time so that the grains at the bottom of the pot dont reach boiling temperature and you'll be fine.

It doesnt sound like you're having any problems with efficiency so you're 90% there.

 

[Bribie G]

Are you measuring the grain temperature as well as the strike water temperature? I find that this makes a fair difference - up to a degree and a half - depending on the time of year.

 

[Crusty]

I don't use gas anymore & some important points you made in your post are the reasons why I now use an electric urn. Heating strike water to mash in temp, mash out temp & sparge if you do one, will most certainly yield inconsistent results with the gas burner. In my opinion, It's simply too hard to nail your temps that closely no matter how hard you try. I use BrewMate & heat my strike water up to 0.5deg over what BrewMate tells me. If it states a 69deg strike in temp, I turn off the urn at 69.5deg, pumping the water with my paint stirrer constantly when approaching temp. I add my crushed grain & for a 66deg sacc rest, I always hit 66.0-66.2deg, every time. I have found with efficiency, a 90min sacc rest followed by a ramp to 78deg for a mash out, pumping with the paint stirrer yields excellent results for efficiency. I get 86% with my system.
I lose 2.5l to trub, 10% boil off & I do squeeze the bag. I also no chill which is awesome.
If you are happy with standard strength beers from 3-6%, brewing in an electric urn with a roasting rack to cover the exposed element is fantastic. If you can get yourself an exposed element Crown urn, you will be amazed how simple BIAB is & you will be bowled over by the incredible beers that come from it. This is my third brewing rig & by far, the best & easiest to use hands down.

 

[GuyQLD]

Hey Bribie,

I buy my grain from Ross in single batches at this stage, so it's vac sealed and at ambient temps usually as I usually brew same day or day after and don't bother cold storage or anything. I just use ambient temp for my calc.

Thanks BDB, Phoney.

Sounds like I shouldn't be skipping mash out so I might put dunk sparging on the back burner for a bit as overly complicating things and just focus on option 1 or 3.

Option three appeals the most to me as far as ease goes because I have a 10L stockpot I can put on the stove at the same time I mash in, and it's usually at the right temp right when the mash is done, so pouring it straight in is easy and gets me to mash out temps instantly.

Although I might try full volume just to take the guess work out for a couple if 15 minutes heating time isn't going to upset it at all. I was just worried that this phase might be problematic as far as adding too much body (heating between 68-78 taking too long).

Thanks.

Edit: And yeah, I did my first no chill last brew. Wish I'd done it earlier since I was relying on ice baths before that. No chill is just so good when you're starting out (And I found a camping shop that does $10 cubes)

 

[Charst]

Are you measuring the grain temperature as well as the strike water temperature? I find that this makes a fair difference - up to a degree and a half - depending on the time of year.

Over thinking the post bribie, he's mashing in at 69 and it's 71 after 45 minutes? Must be measuring the top of the liquid and not stirring prior to doughing in. Grain temp isn't causing an increase.
@guy. Stir your water thoroughly prior to doughing in, aim for 2 degrees above the temp you want to hit and you'll be bloody close. If you can't get all the calculated water required in your pot I'd do a dunk sparge. A 20L food grade bucket should only set you back $20 odd. I'd reserve no more than 5 litres for the sparge but there is plenty of more knowledgable people here to help you with liquor to grist ratios, I just think you should use the max you can in the mash as the method suggests. Will also help with the temp issues to use the most water you can(not more than calculated requirements), more water, less effect the temp of the grain will have.
You sound like a nervous brewer as I was when I started, my advice is to chill a bit, yoru getting the similar efficiency to other biab'ers. Not every number will be hit every time on a brew day, we're not CUB, even they blend batches for consistency. Crack a can and enjoy the day. Cheers.

 

[Maheel]

whats the beer taste like ?

 

[Lord Raja Goomba I]

whats the beer taste like ?

+1

Look in my signature for the link to what I do. It's sort of where I went after BIAB. I'm finding that I can consistently get not only good efficiency, but a fairly replicable process that produces the mostly the same result each time. I can just about not bother dialling in a recipe, and so long as I stick to my (memorised) numbers, I know what the result will be.

When I was having the same issues as you - I just went back to what Maheel said - I still made good beer, cheap. That's gotta count for something.

Goomba

 

[stux]

I use this simple strike temp calculator. Freakishly accurate.

I heat up with gas (for 20-60L batches), and I turn down the gas when i'm about 0.3C away from my target

While I'm cruising up to the target temp I'm mashing the water with my potato masher, which helps get a uniform reading.

I tend to end up with my strike water temp being with 0.2C of the target temp from this calculator, and then dough in... and end up within 0.2C or so of my target temperature

View attachment Strike_Temp.xls

I use a probe style thermometer in my grainbill, which tells me the grain temp

after doughing in I agitate the grain and mix it around for a few minutes and get a nice consistant reading.

these days I do 60L batches and end up with about 8L of trub, so 2-3L sounds about right, and yes, whirlpooling will help. You can rescue about 50% starter wort from the trub if you want.

PS: my last BIAB with Dunk Sparge triple batch I had 90% End of Boil efficiency

 

[felten]

Keep it simple, a full volume no sparge WITH a mash out is what I would recommend, but whatever you pick just stick with it for a while.

If you're having pot size issues there is no reason you can't reduce your batch size by a few litres, other than you end up with a few less bottles.

and lots of stirring

 

[Thirsty Boy]

throw the damn calculator for strike temp away - or at least put it in the drawer for a while.

heat your water to 2c above oyur desired grain temperature... and dont rush it so damn much. heat it for a while, stir it up, stick the thermometer in, see where the temp is. STIR is the important part. Get to your desired temp, stir it up, check temp, wait a few minutes, stir it up, check again..... no need to rush about tipping in the grain, if it cools down, just add a little more heat.

In most instances - getting the water 2 above your desired mash in temp will get you either to your temp, or a little below. If you are going to make a mistake, aim low - its BIAB, adding heat is easy. Turn on heat, stir constantly, turn off heat when you reach a touch below target.

Mash out - helps, helps with consistancy, helps with efficiency. Should you do one?? Nope! you're having some trouble, so keep it as simple as possible. Full volume, No Sparge, No Mash-out. Thats it, nothing else. Get it right, make yourself comfortable with the process - then think about other things.

Once you are getting that right, then the first thing I'd add bach into the process is the mash out - and thats the only thing I'd add in. IMO Sparging of any description is far far more trouble than its worth.

The other stuff - boil off, absorption, trub loss.... well, you admit you are working off assumptions. Stop it. Measure whats actually happening and use those figures instead. All the "assumptions" people tell you to use, are just so your first brew or two end up vaguely in the same suburb you were aiming for. You're supposed to then feedback in the actual results of your brews and stop using assumptions.

plus you are impatient - 5 brews in... jeez. I dont think i had any of this **** even close to consistent before I'd done 20 brews. Relax, use you actual experience to inform your process, keep it as simple as its possible to do and it'll all magically sort itself out in 5 or 10 brews time. Trust me.

TB

 

[JDW81]

throw the damn calculator for strike temp away - or at least put it in the drawer for a while.

heat your water to 2c above oyur desired grain temperature... and dont rush it so damn much. heat it for a while, stir it up, stick the thermometer in, see where the temp is. STIR is the important part. Get to your desired temp, stir it up, check temp, wait a few minutes, stir it up, check again..... no need to rush about tipping in the grain, if it cools down, just add a little more heat.

In most instances - getting the water 2 above your desired mash in temp will get you either to your temp, or a little below. If you are going to make a mistake, aim low - its BIAB, adding heat is easy. Turn on heat, stir constantly, turn off heat when you reach a touch below target.

Mash out - helps, helps with consistancy, helps with efficiency. Should you do one?? Nope! you're having some trouble, so keep it as simple as possible. Full volume, No Sparge, No Mash-out. Thats it, nothing else. Get it right, make yourself comfortable with the process - then think about other things.

Once you are getting that right, then the first thing I'd add bach into the process is the mash out - and thats the only thing I'd add in. IMO Sparging of any description is far far more trouble than its worth.

The other stuff - boil off, absorption, trub loss.... well, you admit you are working off assumptions. Stop it. Measure whats actually happening and use those figures instead. All the "assumptions" people tell you to use, are just so your first brew or two end up vaguely in the same suburb you were aiming for. You're supposed to then feedback in the actual results of your brews and stop using assumptions.

plus you are impatient - 5 brews in... jeez. I dont think i had any of this **** even close to consistent before I'd done 20 brews. Relax, use you actual experience to inform your process, keep it as simple as its possible to do and it'll all magically sort itself out in 5 or 10 brews time. Trust me.

TB

I have to agree with TB on this one. It took me 10+ brews to even get some measure of consistancy. My first three beers were the same recipe with vastly different results.

I've done quite a few brews now and I still don't do a mash out. I choose to keep it simple as I'm happy with my results. I'm not obsessed with efficiency, and working at about 75% I hit all my targets, even still it took time to become consistant.

The more you brew the more you will learn what works and what doesn't. You're the best person the work this out, as it is your gear and your processes. Aim for consistency of strike/mash temperatures and then move on from there.

I think many home brewers become obsessed with numbers and forget it is about making great beer (i'm not suggesting numbers aren't important, i just think you can focus on them to a point where you can't see the forrest for the trees).

Get brewing, keep it simple and enjoy the fruits of your labour.

JD.

 

[bruce86]

hey guys just to jump on board with OP i biab as well and dont technically mash out. should i just chuck the gas on again while i am draining the bag? wil that essentially cause a mash out. or will waiting untill i drain not make too big of a difference. also is there a link to TB's essay cheers.

 

[GuyQLD]

plus you are impatient - 5 brews in... jeez. I dont think i had any of this **** even close to consistent before I'd done 20 brews. Relax, use you actual experience to inform your process, keep it as simple as its possible to do and it'll all magically sort itself out in 5 or 10 brews time. Trust me.

Call it a character flaw if you like, but I do tend to get obsessive about these things. Sure I've made beer (and some of it has been pretty bloody good) but for some people that's not good enough.

I don't want to make good beer, I want to make great beer. While there's no substitute for experience I also don't want to be flailing around blindly for 100 brews until it magically clicks. To that end I read, a lot; and that's probably where I went wrong because I was looking to much at the numbers at the end and over complicating things. I'll slow it down for the next couple and see what sort of numbers I end up with.

Thanks all.

 

[glenwal]

Call it a character flaw if you like, but I do tend to get obsessive about these things. Sure I've made beer (and some of it has been pretty bloody good) but for some people that's not good enough.

I don't want to make good beer, I want to make great beer. While there's no substitute for experience I also don't want to be flailing around blindly for 100 brews until it magically clicks. To that end I read, a lot; and that's probably where I went wrong because I was looking to much at the numbers at the end and over complicating things. I'll slow it down for the next couple and see what sort of numbers I end up with.

Thanks all.

A simple beer (process and/or recipie) done will (often) be far superior to a complex beer (again process and/or recipie) thats done poorly. Start simple, and be obsessive about getting your simple process perfect.

 

[Nick JD]

Call it a character flaw if you like, but I do tend to get obsessive about these things.

Get obsessive about not worrying.

 

[JDW81]

Call it a character flaw if you like, but I do tend to get obsessive about these things. Sure I've made beer (and some of it has been pretty bloody good) but for some people that's not good enough.

I don't want to make good beer, I want to make great beer. While there's no substitute for experience I also don't want to be flailing around blindly for 100 brews until it magically clicks. To that end I read, a lot; and that's probably where I went wrong because I was looking to much at the numbers at the end and over complicating things. I'll slow it down for the next couple and see what sort of numbers I end up with.

Thanks all.

You won't be flailing around for 100 brews before you start to get consistency. Keep it simple and you can't go wrong. My favourite brews are single infusion, single hop addition and they are great beers. I don't always hit the perfect mash temp, but I do control my fermentation obsessively, which I think is the most critically important aspect of brewing (closely followed by thorough sanitisation). Nail the basics, and you'll have a lifetime of great beer.

 

[Thirsty Boy]

hey guys just to jump on board with OP i biab as well and dont technically mash out. should i just chuck the gas on again while i am draining the bag? wil that essentially cause a mash out. or will waiting untill i drain not make too big of a difference. also is there a link to TB's essay cheers.

no, its not the same. Search out one of the essays, there are a few on the same topic so it shouldn't be hard to find. But the crux is that for BIAB, mash outs are for different reasons to mashouts in normal mashtun/falsebottom brewing. INTEGRAL to what you achieve by taking a BIAB to M/O temps is how you get there, in fact how you get there is the point.

You want to get there over a period of time, at least 5 minutes, preferably 10-15 & and you want to do it while constantly stirring the mash. Its the stirring and the gradual rise in temp that does thejob, not the final temperature.

Timer goes off to tell you mash is finished - take lid off pot, turn flame on, thermometer in one hand and mash paddle in the other - stir constantly till it gets to 76-78 and then just pull the bag out as per normal.

TB

 

[bruce86]

Thanks tb will do that next brew for sure.