Mash Thickness - how thin is too thin?

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Mash Thickness - how thin is too thin?

Post by ArcLight » 5 years ago

I BIABed 32 Quarts for 10 pounds of grain with diastatic power and for the first time, didn't hit 70%. Maybe it was the crush, but I'm wondering of 3:2 Q : 1 LB is a bit too thin. I mashed at 150F, dropping to 148 over an hour. I even heated it to 155 and let it drop to 148 for 15 minutes extra. I did squeeze the bag, but no sparge, and no mash out.

Have any of you noticed a problem with very thin mashes? (count only the grain with diastatic power).


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Post by PistolPatch » 5 years ago

I bet you a pound that half of us don't know what a quart is ArcLight :lol:.

The site that originally developed 'The Converter' have thrown the towel in apparently but admin (NME) is investigating whether or not he can make it work again for us somehow. ADMIN NOTE: Unfortunately the edget being referred to here is no longer available. Please read this post for alternatives. In the meantime, to get good answers, it might be necessary for us to give our figures in metric and US. Liquor to grist ratios are one of the hardest ratios to convert and even The Converter would not solve this. Here you go...

A liquor to grist ratio of 32 quarts (8 gals) per ten pounds or 3.2 quarts per pound equals...

In metric, approx 30 L per 4500 grams of grain or 6.7 L per kilo.

(That took me ages :angry:).

These are normal liquor to grist ratios for BIAB so you should not be finding a decrease in efficiency. (When you hear the words thin and thick mash, these only apply to traditional brews not BIAB - they are two totally different worlds).

I reckon the first two issues to consider here Arc are as follows...

1. When it comes to efficiencies, one brew can't really give you any valuable info. For example, what if the grain wasn't weighed correctly? All your efficiency figures will be lower. Worse still is when only one gravity and volume reading are taken on a single brew.

Most brewers take very few measurements on a single brew which means there are no double checks. There are three good opportunities in a brew to take volume and gravity checks. Even if you do take the time to do these six measurements, you will find they rarely agree so how much can you rely on two measurements - one gravity and one volume? You can't.

2. An efficiency of 70%, on say a 1.050 brew with reasonable hop and trub management would be about right if we were talking about 'Efficiency into Fermentor' but very poor if we were talking about Efficiency into Kettle or at the End of Boil.

Efficiency into Kettle (or at the End of the Boil) is not the same as Efficiency into the Fermentor. They are two totally different numbers. This is a major communication problem in the brewing world atm, just like metric and US units but worse because at least in metric/US we are aware there is a problem :P.

Current brewing terminology is like ten different currencies talking to each other and they all actually think they are speaking the same language :o.

So Arc, I reckon just do another brew. Make sure your grain is weighed correctly. (How will you double check that?) Also commit to taking three volume readings and three gravity readings on that brew.

After three brews and doing all the above, we can then start to see some averages develop. These averages are what tell the real story.

In medicine, Dr House says, "Everybody lies." In brewing, Dr Brew House would say, "Everybody and every instrument lies albeit unwittingly."

So, take it easy and don't jump to conclusions on a single brew, tempting though it is :drink:. There's lots of easy, simple, interesting experiments all of us brewers can do and get right but still haven't spent time on. Look at this thread.

Until we get good answers to the very simple question asked in that thread, how can we even begin to explore anything else :think:?

It's all good fun though :P,
PP
Last edited by PistolPatch on 10 Oct 2012, 23:15, edited 2 times in total.
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Post by Yeasty » 5 years ago

Bu~~er PP you beat me to it..I must have took to long finding out what a quart was. :idiot:

One thing you said Arc is bugging me..(and PP)
ArcLight wrote:and for the first time, didn't hit 70%.
So are you saying your normal efficiency is 70% ? this is into Fermenter right ? You didn't quote what you actually hit, was it way off ? can you post some munbers ?

Questions questions I know but as PP has proved your mash ratio is in the ball park we need to look elsewhere.

Yeasty
Last edited by Yeasty on 11 Oct 2012, 00:04, edited 2 times in total.
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Post by ArcLight » 5 years ago

Thanks PP and Yeasty.

1. When I talk about Efficiency, I always mean 'Efficiency into Fermentor'. My recipe expected 1.055 and I had 1.051. Not a disaster, just a bit off. Had I sparged it would have been spot on 70%. maybe it was the crush, who knows. I did not mash out either, I lifted the bag at 68C. Of course I want 80% ...

2. I will try and use metric from now on.
Quarts, Pounds, Ounces, Faranheit <= :headhit: :sneak: :shoot:

Grams (Kilos), Liters, Celsius <= :thumbs: :salute:

My next batch is close to 7K, so I will mash with 24L, and sparge with 8L.
I will mash at 65 for an hour, and maybe even give it a boost to 68 for 15 minutes, before mashing out at 75.


Yeasty,
I use 70% as a generic minimum threshold. I get better than that, but 70% is not bad.
So my comment "didn't hit 70%" really meant, I didn't break what I consider an acceptable floor.


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Post by joshua » 5 years ago

Arclight, Is 1L/1.1Kg too stiff to wash the grains??
I use 1L/0.5kg and get a very good wash from the grains.

If the grains come out of the mash at 1.040, a dunk/teabag sparge should come out around 1.020, whereas a stiff Sparge may only wash down to 1.03x from the grains, this leaves more sugars in the grains.

Just MHO, on what I use.

Also, with a Thin Mash, I need to stir/recirculate often, to keep the grains from settleing into Sludge, I found a good stir/recirculate can increase the Gravity by a few points.
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Post by ArcLight » 5 years ago

>>Also, with a Thin Mash, I need to stir/recirculate often, to keep the grains from settling into Sludge, I found a good stir/recirculate can increase the Gravity by a few points.

When I did stovetop BIAB I frequently mixed. Now that I have a 57L lettle, I did not stir. Maybe that contributed? Maybe I should mix after 30 minutes. I just assumed the mash was so thin that the grain wasn't compacted. But it's worth trying.

>.Arclight, Is 1L/1.1Kg too stiff to wash the grains??
I use 1L/0.5kg and get a very good wash from the grains.

I don't know what the correct ratio is. Probably 1L / .5K is a good ratio. I think one needs to sparge by submerging the gain in water so that its completely covered, stir it up for a bit, let it sit a couple of minutes, stir it up, and then raise the bag and squeeze it.

The only problem is if one adds more water, the boil must be adjusted to evaporate it. This is more of a problem for bigger grain bills. I don't want to mash thinner than 3L : 1K. When one has 7.5K thats around 23:L. Plus another 15L for the sparge is a lot of extra water.

Maybe mash 20L for longer, and sparge with 10?

I'll have to play around with it. Its easier with 5-6K for a 20L batch.


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Post by PistolPatch » 5 years ago

Hey there Arc :peace:,

About 6 month ago, I did 6 side by side double batches to see if sparging made any difference in mash efficiency. I think the difference was a 1% on average. In other words...

If you can put all your water into the mash, then do it.

I'm going to do a series of mini experiments to double-check the first experiment around Xmas time but for now, the only reason I can see for doing a sparge is if your kettle is too small to handle all the initial water. There's heaps of disadvantages to sparging though - time, mess, extra vessels - basically double the work :o.

Also, I mentioned it above but I think this point has got missed. You can't tell anything from one brew...

Making an assumption based on one brew's numbers can easily become a permanent and unnecessary mindset that will cost you.

I think sparging when there is no need is a good example of this.

Does that make some sense?
:scratch:
PP
Last edited by PistolPatch on 12 Oct 2012, 07:13, edited 2 times in total.
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Post by joshua » 5 years ago

Yes, PP, you ONLY need to Sparge/Rinse the grains to make 23L of beer in a 28L kettle, Or Mine a 30L.
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Post by alanem » 4 years ago

PistolPatch wrote:I bet you a pound that half of us don't know what a quart is ArcLight :lol:.

The site that originally developed 'The Converter' have thrown the towel in apparently but admin (NME) is investigating whether or not he can make it work again for us somehow. In the meantime, to get good answers, it might be necessary for us to give our figures in metric and US. Liquor to grist ratios are one of the hardest ratios to convert and even The Converter would not solve this. Here you go...
I guess I may be a bit late with this and I'm not sure if it.s allowed but there is a great site for converting it's called convert-me. it will convert anything in seconds.
Last edited by alanem on 13 Nov 2012, 04:38, edited 2 times in total.
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