Not Getting Full Potential From Mash

[Tony]

Awsome Post TB!

I tend to achieve higher efficiency but using a slow sparge..... like 1 or 2 hrs to drain the mash and sparge is only ever a sinlgle sparge that is sort of a mix between a batch and a fly where i drain the mash tun to the kettle and them re-fill it again and circulate it for 5 or 10 min through the herms but dont stir or disturb the grain bed at any time.

I treat my sparge water with some CaSo4 or CaCl depending on what im making and use a bit of acidulated malt in the mash the help keep the PH right. I always drain my mash tun at mash tamp and sparge cool at about 71 to 72 deg.

I have noticed when i rush and sparge quickly over say 20 min, my efficiency drops to around 70 to 75% and the beer just isnt as nice. Perhaps im catching more flavour compounds with the slow sparge and less tanins with the low temp sparge?

It seems to work at my place anyway.

Cheers

 

[Mantis]

Thats another thing I am doing wrong then. I have drained the mash and sparge way too quickly by the sounds of it.
Much refining to do :icon_cheers:

 

[manticle]

When I batch sparge, I leave the water in for at least 10 minutes (also allowing the grain bed to settle).

 

[Tony]

Thats another thing I am doing wrong then. I have drained the mash and sparge way too quickly by the sounds of it.
Much refining to do :icon_cheers:

When i sparge fast i get fairly weak runnings and very little colour addition to the water.

When i sparge slowly i ged a deeper saturated colour from the grain and more sugars.

I think when you sparge quickly, the water just runs over hte grain and washes off any residuals on the surface. When you sparge slowly it allows time for the sugars and other compounds like colour, still held within grain particles in the mash to be drawn out and into solution in the water. This naturally results in higher efficiency from the mash.

After reading thirstys post, im thinking that the extra colour i get in the sparge water are these compounds that are associated with malt flavour and aroma in the finnished beer. fast sparge water tastes dull to me and i usually stop the sparge and just top up with water if im in a hurry to avoid anything nasty. But if im sparging slow i let every drop into the kettle because its better tasting. I guess the word is maltier!

Here is another thing to back up slow sparging i just thought of! Its open to discussion of course.

When you read malt specs it usually states conversion times of around 10 to 20 Minutes. Why do we mash for 60 minutes... or longer? I know my mash is sweet by the time i finnish stiring it all in! Perhaps its to give the sugars and other compounds time to form and soak out into the water? It's possible things are the same with the sparge.

cheers

 

[Screwtop]

Thats another thing I am doing wrong then. I have drained the mash and sparge way too quickly by the sounds of it.
Much refining to do :icon_cheers:

When I batch sparge, I leave the water in for at least 10 minutes (also allowing the grain bed to settle).

Like Tony, I increased my sparge drain time years ago in the quest for increased eff. Still many brewers have posted on here that they achieve high eff but drain quite quickly. So I thing is a case of.............it depends............maybe on your mash tun geometry and manifold. Try lengthening the drain time for your first runnings, then sparge runnings and see what effect this has on your efficiency. I too sparge over an hour, tried 90 min without much increase in eff, cut back to 20 min and mash efficiency drops from nearly 90% to the low 70's. Pretty much it's dependent on your kit and process. Efficiency also increased for me when I changed from 60 min to 90 min boils. The extra couple of litres required for sparging due to the extra boil off volume managed to get that little extra in the way of sugar out of the grist and lift my eff.

Cheers,

Screwy

 

[gjhansford]

When I batch sparge, I leave the water in for at least 10 minutes (also allowing the grain bed to settle).

This thread has been extremely helpful and thought provoking. Thank you all for your comments and suggestions.

My 2 bits worth (20 litre 'standard' ABV brews) ...

I mash at a ratio of 3 litres per Kg of grain - usually 15 litres and 5Kg - (which includes 4% Acidulated Malt for Ph correction - all brews except the stouts) for 45 minutes and run off all I can - about 10 litres - of high gravity wort into my kettle. I fire up the burner immediately, bring it to a boil and keep it going while ...

I add 10 litres of water (at a temp that gives me the same mash temp as the first mash) back into the mash once the first run off has finished, give it a good stir and leave for another 45 minutes.

After the "second mash" or "long batch sparge" I run a second 10 litres off into the now boiling kettle and fly sparge fairly quickly (about 10 minutes) with another 8 litres of mash temperature water.

In all, in 90 minutes, I get 27 litres of 1.044 pre boil wort, which I now boil for 60 minutes with the required hop additions to end up with 20 litres of 1.048 to 1.050 wort in the fermenter.

It's a sort of double mash idea that I read used to be done, and still is apparently, in some UK breweries, except there they make two brews, one from the high gravity first runnings and a second brew from the second loweree gravity runnings, and blend them after fermentation.

Or it's a batch sparge with a long wait before running off the sparge water.

The 30-40 minute boil of the first runnings also seems to improve the final beer.

Afrer reading this thread I'm thinking of changing two things - slowing the final sparge even more, and increasing the termperature of the final 8 litres sparge water.

Any comments or suggestions?

 

[manticle]

I'll try the tap open less next time I brew so it drains slower and see what that does to my gravity. While it's never concerned me overly it is interesting to see what effect a change in process has.

 

[Screwtop]

When i sparge fast i get fairly weak runnings and very little colour addition to the water.

When i sparge slowly i ged a deeper saturated colour from the grain and more sugars.

I think when you sparge quickly, the water just runs over hte grain and washes off any residuals on the surface. When you sparge slowly it allows time for the sugars and other compounds like colour, still held within grain particles in the mash to be drawn out and into solution in the water. This naturally results in higher efficiency from the mash.

After reading thirstys post, im thinking that the extra colour i get in the sparge water are these compounds that are associated with malt flavour and aroma in the finnished beer. fast sparge water tastes dull to me and i usually stop the sparge and just top up with water if im in a hurry to avoid anything nasty. But if im sparging slow i let every drop into the kettle because its better tasting. I guess the word is maltier!

Here is another thing to back up slow sparging i just thought of! Its open to discussion of course.

When you read malt specs it usually states conversion times of around 10 to 20 Minutes. Why do we mash for 60 minutes... or longer? I know my mash is sweet by the time i finnish stiring it all in! Perhaps its to give the sugars and other compounds time to form and soak out into the water? It's possible things are the same with the sparge.

cheers

Funny you should bring this up Tony. Was contacted recently by a brewer who made a recipe of mine for an Aussie Lager. Dead simple thing, sometimes I make it with Pale and some sugar and other times some Galaxy or Pils Malt and less sugar. Single Cluster hop addition, a good summer quaffer along the lines of a XXXX, as a gateway beer to offer the typical megaswill drinker. He made the beer but said it was way too pale. I use 10% sugar with Pale malt or 5% with Galaxy or Pils and the colour is usually a little darker than that of XXXX. I asked him about his boil time, thinking that my usual 90 min boil may contribute to the darker outcome. Made the same beer last Sat (as an ale this time instead of a lager) and noticed how dark the wort was in the kettle prior to the boil. Looks like getting more colour from a long sparge is also a contributor......Interesting.


Cheers,

Screwy

 

[paulwolf350]

Funny you should bring this up Tony. Was contacted recently by a brewer who made a recipe of mine for an Aussie Lager. Dead simple thing, sometimes I make it with Pale and some sugar and other times some Galaxy or Pils Malt and less sugar. Single Cluster hop addition, a good summer quaffer along the lines of a XXXX, as a gateway beer to offer the typical megaswill drinker. He made the beer but said it was way too pale. I use 10% sugar with Pale malt or 5% with Galaxy or Pils and the colour is usually a little darker than that of XXXX. I asked him about his boil time, thinking that my usual 90 min boil may contribute to the darker outcome. Made the same beer last Sat (as an ale this time instead of a lager) and noticed how dark the wort was in the kettle prior to the boil. Looks like getting more colour from a long sparge is also a contributor......Interesting.


Cheers,

Screwy

I actually split the batch Screwy, the first one was brewed with an ale yeast and was very pale, the second half was fermented with s189 lager yeast and was the right colur, same wort different results, so now i am at a loss to explain it. Although my sparge may be a contributing factor

Paul

 

[manticle]

I'm assuming you guys are fly sparging. Besides opening the tap up less so as to drain slower, is there any benefit for batch spargers to leave the sparge water in for longer (longer than the 10 minutes I do for example). My understanding of the old English sparge is that it is almost like a second mash.

 

[Nick JD]

Wouldn't a long sparge in the 70s be darker due to more tannins steeping from the husks?

 

[manticle]

I don't think so. My understanding of how and why is limited but I think tannins are harder to get out than most people believe. Oversparging may be one factor. If you don't get tannins by boiling the mash for 20 + minutes during a decoction then there must be some other factor.

Someone else should jump in with better info.

 

[Screwtop]

I actually split the batch Screwy, the first one was brewed with an ale yeast and was very pale, the second half was fermented with s189 lager yeast and was the right colur, same wort different results, so now i am at a loss to explain it. Although my sparge may be a contributing factor

Paul

Does anyone else find this weird? How did the gravities end up Paul? Have never split a batch of pale beer using different yeasts.

Cheers,

Screwy

 

[Tony]

Wouldn't a long sparge in the 70s be darker due to more tannins steeping from the husks?

Tannins are acids like those extracted from the hops..... only they are generally considered a flaw in the beer. They are a flavour compound and as far as i know...... dont contribute colour

They are generally extracted from a high pH in the mash or sparge, or high temperatures or a combination of both.

My understanding only...... Thirsty.... can you elaborate this ?

 

[Ross]

Does anyone else find this weird? How did the gravities end up Paul? Have never split a batch of pale beer using different yeasts.

Cheers,

Screwy

Yeast can take colour out of a brew (especially prevelant when adding fruit). I'm guessing that the bottom fermenting lager yeast has scrubbed out less of the colour than the ale yeast. Certainly when i draw test samples from a S-189 wort they are very clear compared to an ale yeast.

Cheers Ross

 

[Thirsty Boy]

Ross is spot on the money - different yeast can strip colour at different levels - although I believe that they all strip colour to some extent.

If you are a wine guy looking for a vibrant red.. you want a yeast that doesn't strip colour.. if you are a pale lager brewer looking to minimise colour and want to brew the palest beer you can.. your are after the opposite.

Tannins = Polyphenols - contained primarily in the husks of your malt and in hops.

NOT - a bad thing. In fact an absolutely vital part of the larger brewing process. They contribute flavour & when oxidised colour, are part of many of the chemical changes in the boil, combine with proteins to form break material, are anti oxidants which protect beer from aging. All manner of stuff.

They can be a flavour and stability issue.. in excess. Too many tannins can give a grainy or husky flavour to a beer and can lead to an astringent "mouthfeel" which together with other flavours can make a beer seem harsh and perhaps overly bitter.

Now you are getting the hop polyphenols regardless ... so the one that most people focus on is the stuff from the grain.

Dont sparge too hot
Dont sparge too long
Dont grind too fine
Check your pH
Cut your sparge at 1.010

Sound familiar?

Grain polyphenols are extracted from every mash.. all the way through the mash and sparge. But the things in the list above have valid origins. Temperture increases the rate of tannin extraction, increasing pH increases the rate of tanning extraction. Finer crush increases the surface area of husk available for extraction to occur through...

Its generally not a really problem unless you layer those things on top of each other. Hotter sparge.. sure, you get more polyphenols - higher ph, yep.... more. But does more equate to excessive?? In most cases the answer is probably no.

If you combine them though... then you start to get into danger territory. pH is you main concern, because sparge temperature is already hot enough to be an issue (in combination) and the main trigger point is about pH 5.9-6.0 -- its not a switch, tannin extraction occurs below that level.. but my understanding is that above that approximate pH range, the rate at which tannin extraction occurs, increases in a greater than linear fashion... the graph curves upwards, quite steeply.

And where can you get pH higher than 6.0?? Water!! Sparge water to be exact. The more water you add and the less diluted by acidic "mash" it is, the higher the pH. So as you proceed through your sparge, your mash temperature progressively goes up and the pH at any point in the lauter tun is increasing as water dilutes the mash liquor. Eventually at a given level, the temperature will max out and the pH will approach that of water (say 6.5-7??) And tannins will be being extracted a fair old rate.

The thing that makes it a little complicated - is that this happens unevenly through the lauter tun - naturally enough, it occurs first at the top of the tun where you are adding in the sparge water.. the sugars etc get washed away and you are basically pouring hot, high pH water onto spent grain... and extracting tannins -- but at the same time, down the bottom of the tun, you are happily running off good sweet wort. The layer of high pH and tannin extraction (plus all the tannins you already extracted) moves down through the tun as the sparge proceeds; and eventually they will come out the tap.. the trick is to stop before they do.

So its not about avoiding tannin extraction... if you sparge in any sort of an efficient manner.. you are going to be extracting excessive tannins from your grains. What its really about - is making sure you leave them in the lauter tun.

If you are really looking for high efficiency - you can do what we do at work. Constantly monitor the gravity of wort being run-off. The gravity drops and drops ... the natural assumption is that it would just keep going till it gets to zero. But it doesn't. Somewhere around 1 plato, it starts to head back up again and goes back up to 3-4 plato before dropping off again. We call it the gravity break. Guess what it is?? Its tannins!! As the sugar gets washed away.. the gravity drops to the minimum point. At that point the liquid from that "hot, high pH" zone starts to come through, carrying with it all the polyphenols etc it has extracted and pushhing the density back up. So to extract teh most sugar without getting all that.. you watch the gravity and as soon as you see it bottom out .. you cut the run-off and the rest goes to drain.

Easy at a big brewery with inline density measurement.. what about you at home?? Well, thats where the "dont sparge further than 1.01 (about 4 plato) thing comes from. You could go lower... but by cutting off at that level, you make a compromise. You miss a little sugar.. but you also make sure you miss that layer of polyphenols too.

What about batch sparging??

Well, its pretty much not an issue. You dump in all your water, mix it up and drain it out. There has never been a point at which you are adding pure hot water to grain that has already given up everything but its tannins. Yes, the temp goes up and the pH does too... but never enough to put you in the danger zone. The more batches you do, the closer you will get though. Still - hands up who does more than three batches??

So the Tannin thing is really only for people who sparge by adding pure water at one end, while draining wort from the other. For instance Tony where he adds his sparge water and then re-circulates it... not him!! He mixes that pure water in, so its no going to happen with his technique.

And its only an issue if you get greedy.. stop at a sensible point and you avoid the issue. If your system is well designed, and you pay attention to your pH and temperatures and your technique.. then there is no reason why you couldn't expect to get around 95% mash efficiency from a continuous sparge and no issues.. but the less "good" your system and technique is... the lower the level of efficiency you can expect before you hit trouble. You can get 95% efficiency on your crappy system... just keep sparging. You will actually get a few bonus gravity points from all the tannins!! Enjoy the happy satisfied glow during your boil... it wont last into the glass.

That's how it all works in fevered imagination anyhoo.

Thirsty

 

[Tony]

So the Tannin thing is really only for people who sparge by adding pure water at one end, while draining wort from the other. For instance Tony where he adds his sparge water and then re-circulates it... not him!! He mixes that pure water in, so its no going to happen with his technique.

And its only an issue if you get greedy.. stop at a sensible point and you avoid the issue. If your system is well designed, and you pay attention to your pH and temperatures and your technique.. then there is no reason why you couldn't expect to get around 95% mash efficiency from a continuous sparge and no issues.. but the less "good" your system and technique is... the lower the level of efficiency you can expect before you hit trouble. You can get 95% efficiency on your crappy system... just keep sparging. You will actually get a few bonus gravity points from all the tannins!! Enjoy the happy satisfied glow during your boil... it wont last into the glass.

Very VERY true!

I wouldnt even dream of doing a second sparge....... never have never will. If im short on my boil volume i top up with water strait into the kettle. I then open up the mash tun and let the last liter or 2 dribble out into a pot while i boil the brew and use the last bit of runnings for starters! I will generally get between 2 and 4 liters at about 1.020. I fill 2 liter vinigar bottles (they are thicker and stronger and dont split in the freezer) and freeze strait away. Defrost when you want them in a sink full of warm water and (Edit: after boiling down) you get a 1 liter 1.040 starter.

Now thats getting the most from the mash!

cheers and thanks again Thirsty :beerbang:

 

[Nick JD]

A bottle of Tannic Acid (pH 6).

 

[Mantis]

This is an extremely informative thread and comes at a good time for first time mash tun users like me and others.
Many thanks TB and Tony for clearing a lot of stuff up.
I will attack the next brew with more confidence and knowledge now

:icon_chickcheers:

 

[Mantis]

Did a smash today with the same grain bill as last brew being 9kg of JW Trad Ale

Followed Tonys advice above re: one sparge only and sloooooww runoff.
The other thing I did different was add 3tsp of CaCl to the water along the way

Anyhoo with the 3 mash tun brews so far I have gone 63,68 and today 76% eff into the cubes
Now I am happy with the process I can do some more adventurous brews, and maybe with some crystal and darker malts in the mix, the eff might even rise some more, but I am more than happy with 76.

:icon_chickcheers: