# Water To Grain Ratio - Mash Efficiency?



## reviled (29/11/08)

Hey guys

Last two brews ive done, I used a few litres less water for my initial mash, and then added boiling water to bring up to mash out, and boil...

So instead of bringing 27 litres of water up to mash temp, I started out with say 20-22, and then when bringing to mash out, added another 4 litres or so (I only have a two ring burner, so adding boiling water helps) 

The thing is, my efficiency's up, instead of getting 65-70%, im getting 70-75% Which is awesome, but why? Everything else im doing is the same, this is the only process ive changed.. For those who dont know, I BIAB... 

Is there a reason behind this? Or is it just one of those things? :huh:


----------



## razz (29/11/08)

Morning reviled. In the previous brews were you mashing out? I find that hitting 78-80 degrees for a mash out is a good way of getting a few extra points out of a brew.


----------



## warra48 (29/11/08)

You are raising the temperature of your mash with a mash out addition of water. 
That gives you a higher temperature than your mash temperature, making the sugars more dissolvable, and making for easier draining of the wort.
Thus, you drain more sugars than you were doing previously, and that gives you the increased efficiency.


----------



## reviled (29/11/08)

Previously ive just been raising the temp with the burner, but with my 2 ring, and me stirring constantly as per Thirsty Boys instruction, it takes about a minute a degree, sometimes more... I used to skip mash out but got an extra 5-8 points by doing a mash out, and now ive just scored extra points doing it this way?? 

So by adding boiling water it takes alot less time, but im still getting to the same temp, so I dont see how its affecting the efficiency, its not like a normal sparge?


----------



## Thirsty Boy (29/11/08)

Depends - were you raising to the mash out temperature before? If not, you should have been. Remember, in BIAB there is no "sparge per se - so, when brewers of the "normal" variety skip a mash out, all that is happening is that they run a mild risk of their fermentabily profiles changing during a long sparge. On the other hand, when a BIAB brewer skips the "mash-out" step, what they are doing is pulling the bag and therefore lautering at whatever their mash temperature is - which is going to be somehwhere around about 10C lower than a proper sparge/lauter temperature.

Lower temperatures mean that the sugars are more viscous and less soluable - and will probably result in lower extraction rates (or efficiency) - raising the temp up to a mashout/sparge temp is something that I recommend all BIAB brewers do, and in the fe trials I ran on what difference it makes - it equates to around 5-7 percent increase/drop in mash efficiency.

so that could be it - 

If you were already raising your mash temperatures - then I suspect something may have been slightly askew in your previous technique, something that has been altered by the act of adding the extra water - maybe more thorough stirring, I seem to recall you saying (and I might recall incorrrectly) that you were mashing with the bag closed?? A mistake IMHO, perhaps you opened it up to add the water?? Not sure. Think laterally about what you have had to do differently in order to add that water.

The reason I mainly suspect a suddenly rectified fault in technique is, that your efficiency (assuming you mean measured at pre-boil, or mash efficiency) was pretty low - I would normally expect a BIAB brew of within a point or so of 1.050 gravity, to give you an efficiency in the 70's - heading towards the high 70% range the lower the gravity of the brew.

So to me it looks like you are now getting what you should be getting, and something was wrong before.

OR....

You just weren't getting good efficiency in your mash/conversion before. And this has been helped by lowering the L:G ratio. It might be a straight enzyme thing, it might have something to do with pH ... or it could be a lot of other things.

It doesn't really matter though - if what you are doing now works with your equipment. Ie the boilig water helps to get you to sparge temp... then dont argue! take the improvement and call it good. hats calle becoming an experienced brewer.

Cheers

TB


----------



## reviled (29/11/08)

Thirsty Boy said:


> Depends - were you raising to the mash out temperature before? If not, you should have been. Remember, in BIAB there is no "sparge per se - so, when brewers of the "normal" variety skip a mash out, all that is happening is that they run a mild risk of their fermentabily profiles changing during a long sparge. On the other hand, when a BIAB brewer skips the "mash-out" step, what they are doing is pulling the bag and therefore lautering at whatever their mash temperature is - which is going to be somehwhere around about 10C lower than a proper sparge/lauter temperature.
> 
> Lower temperatures mean that the sugars are more viscous and less soluable - and will probably result in lower extraction rates (or efficiency) - raising the temp up to a mashout/sparge temp is something that I recommend all BIAB brewers do, and in the fe trials I ran on what difference it makes - it equates to around 5-7 percent increase/drop in mash efficiency.
> 
> ...



Hey mate, cheers for the detailed response...

When I first started, I wasnt bringing to mash out, and I was getting about 70%, this was for my first two brews, then after that it dropped to 60%ish, so I started bringing up to mash out, and I began to get 65-70%... I dont mash with the bag open, I did say I could "open the bag up" in regards to decoction, but I said it wrong, I more meant open the lid :lol: Sorry...

I also found it strange how I got a high efficiency first two brews, without a mash out, then it dropped drastically? Maybe I was taking readings wrong or something? 

But now ive simply changed how quickly im getting to mash out, with a lower water to grain ratio to start out with, and using boiling water to help me get there, which has given me another 2-7 points and I was just wondering if there was a reason, but obviously nothings that simple with AG  

Man, so if something was wrong before, I wonder what it is/was? :huh: maybe I need to check a few things like PH etc...

And dont get me wrong, im not complaining about a higher efficiency, was simply wondering why so that I could try to work on improving it..


----------



## Thirsty Boy (29/11/08)

not sure - but till you get the hang of things, and especially taking reading, things can bounce around a bit when you first get going..

Like I said, you have hit on a technique that works for your system, might as well stick to it and see what happens.

As I mentioned in my other post, BIAB (being a no-sparge technique) is reasonably sensitive to the gravity of the brew. I would be expecting low 70% figures for a "big" beer and high 70's or better for a small beer.

Stirring, hitting your temps, step mashing, pH, crush, decoction ... they can all affect efficiency. But once you are sort of in the 70's somewhere, then you are past the "must be doing something wrong" point and the rest is all about refining your technique till you get consistency. Consistency in your efficiency is so much more important than it being high.

You shouldn't have to worry too much about pH etc etc... unless your water is way out of whack - and that would be consistent across your brews. It could be that the homebrew shop crushed your grains differently, maybe they re-set the gap on their mill, stuff beyond your control. Jst following teh basic BIAB routine should get you into the 70% range - and remember to give the mash a good stir up before you pull out the bag.

You'll get it sorted.

Cheers

TB


----------



## reviled (29/11/08)

Cool buddy, thanks for the info :icon_cheers:


----------



## drsmurto (30/11/08)

Are you now sparging with a higher volume due to less water to dough in with?

I found that reducing my initial water to grain ratio from 2.7 to 2.3L/kg i was able to use that few extra L of water to sparge with getting more sugar form my grain and upping my eff from 70 to 75%.


----------



## Bribie G (30/11/08)

I've seen it on the forum somewhere but how much water does a kilo of malt 'take away' with it even though it has been thoroughly drained? I'm going to use a 40L urn for BIAB and my regular recipes will probably be five kilos of malt/crystal. I'd like to be in the position of being able to mash out with enough very hot water to take the level as far as possible to the top of the 40L then hoist the bag, and wonder how much sweet liquor would I expect to be left after doing that? I'm getting a light block and tackle for my garage skyhook this week and intend to hang the bag over the urn and drain it thoroughly. Obviously with a dead-set constraint of 40L I will need every trick in the book to get good efficiency.


----------



## Adamt (30/11/08)

A generally accepted estimate for this is 1L lost per kg of malt.


----------



## Bribie G (30/11/08)

Adamt said:


> A generally accepted estimate for this is 1L lost per kg of malt.



Sweet, that gives me far more leeway than I thought. :icon_cheers:


----------



## warra48 (1/12/08)

I often see this figure of 1 L/kg, but in my experience it is closer to 1.5 L/kg.


----------



## Tony (1/12/08)

I lose 1 liter / KG. 

when i have finnished my sparge and the kettle is full, i leave the mash tun tap open the a tube running to a SS pot on the ground for about an hour. 

This usually recovers about 1/3 to 1/2 liter/kg and i boil this down to make starters.

cheaper than buying extract!

cheers


----------



## Thirsty Boy (1/12/08)

BribieG said:


> I've seen it on the forum somewhere but how much water does a kilo of malt 'take away' with it even though it has been thoroughly drained? I'm going to use a 40L urn for BIAB and my regular recipes will probably be five kilos of malt/crystal. I'd like to be in the position of being able to mash out with enough very hot water to take the level as far as possible to the top of the 40L then hoist the bag, and wonder how much sweet liquor would I expect to be left after doing that? I'm getting a light block and tackle for my garage skyhook this week and intend to hang the bag over the urn and drain it thoroughly. Obviously with a dead-set constraint of 40L I will need every trick in the book to get good efficiency.



Bribie - in BIAB you are able drain the grain more thoroughy than guys with a mash tun can - you will probably find that you are losing between 0.75 l/kg to 0.5l/kg. Depending on how big a grain bill you have and/or whether you decide to squeeze the bag a bit or not.

If you have a grain bill on the order of 4kg and you give the bag a good squeeze - probably around 0.5 l/kg

A bigger harder to drain/squeeze amount - 0.75kg/L

That all assumes that you squeeze the bag a bit (not wringing it out but a decent squeeze) and that you catch every last drop tht comes out of it... and why wouldn't you. I boil for 90 mins usually and I keep catching teh drips right up till the boil has been going for 30mins, then I dump the last dribbles in, stir and take volume and gravity figures for my efficiency.

calculate for 0.75L for your first couple of brews, then work out what you actually get and use that in future brews.

TB


----------



## raven19 (1/12/08)

Tony said:


> I lose 1 liter / KG.
> 
> when i have finnished my sparge and the kettle is full, i leave the mash tun tap open the a tube running to a SS pot on the ground for about an hour.
> 
> ...



Not just a pretty face then Tony!

Thanks for this tip, I shall be keeping this in mind come AG time in a few weeks. Picking up my elements for the kettle today...

Cheers! :icon_cheers:


----------



## buttersd70 (1/12/08)

Agree with warra it's closer to 1.5 ish for 'regular' tun, very interesting about the biab loss being less......
And another little gem from Tony....I presume you boil fairly hard to reduce the volume and bring it back into the 1030-1040 range for the starters....give that man a cigar.


----------



## Bribie G (1/12/08)

Great info, thanks guys, I'll be fine now as long as SWMBO doesn't walk into the garage and find me giving the bag a big juicy bear hug :unsure:


----------



## warra48 (1/12/08)

Nice one, Tony.

I must say that when I toss my spent grains on the vege patch, as the last clean up job on brew day, I usually see some wort still in the bottom of the mashtun, even though I think I've drained all I can out of it at the end of the sparge. 

Will give this a shot next brewday.


----------



## stueywhytcross (1/12/08)

reviled said:


> Hey guys
> 
> Last two brews ive done, I used a few litres less water for my initial mash, and then added boiling water to bring up to mash out, and boil...
> 
> ...



Check out the attenuation experiments with Kai Troester Link, (20th November) He did 70 experiments from memory, using different temps, different ratios and measuring efficiency and attenuation. Worth a listen.


----------

