kg/l mash calculation

[data790]

Hi,

Probably a question already answered but can anyone explain why the mash calculation of thick wort kg/l or lbs/l 1.5-5 ect... varies and when you would adjust this? I recently made an Irish red and it came out a tasting a little watery - though it has only been a week and I kegged on Saturday before testing the beer engine on Sunday (I like to make sure no nasties get into my beer and taste.

Additionally, I am looking for a good book on brewing all grain beer so that I can start making adjustments to my ales and reduce this watery taste and make them more full bodied. Can anyone suggest such a book?

Cheers all

[Jocky]

Supposedly thicker mash will result in more body and fewer tannins, which is great for those chewy, malty darker beers, but it's a way finer difference than adjusting mash temperature. Certainly many BIAB brews are done with very thin mashes with little noticeable effect.

[Charles1968]

According to braukaiser it's a myth that thick mashes give more body:

http://www.braukaiser.com/wiki/index.ph ... _thickness

BIAB brewers will tell you mash thickness makes no difference, and that's my experience from doing occasional thin mashes in a mash tun.

The only drawback from a thin mash is that mash pH ends up slightly higher as there's a fixed amount of acidity in the grain but a larger volume of water & therefore bicarbonate. On the other hand, if you mash thin you have a much smaller sparge (or none at all) so there's less risk of extracting unwanted tannins when sparging.

Efficiency is also slightly higher if you mash thick and then sparge the hell out of the grist, which is probably why commercial brewers do it. Most home brewers (BIAB brewers excepted) follow this model by convention but it isn't necessary. As the Braukaiser article says, a thin mash actually achieves better conversion, so if you want to avoid oversparging you'll likely get better efficiency from mashing thin than thick.

[BenB]

Yes, I'm not sure I've ever quite believed the science behind the thin mash causing a thinner beer. The thinking is the thin mash means the enzymes are more dilute so they work slower. But surely in relation to the concentration of grain they're the same. I suspect it's one of those things that people have done and not really tested!!!! It's a theory perpetuated by being stated in the online version of How To Brew and most of what's in that has subsequently been withdrawn I should grab my paper copy to see if it's still in there- quite a bit was removed between the online version being published and the paper copies being published...

[Charles1968]

I prefer Braukaiser to Palmer as Braukaiser actually tests theories himself rather than regurgitating stuff from old brewing reference books, so he's better at uncovering myths.

In a standard chemical reaction, the reaction rate does rise at higher reactant concentrations, but mash chemistry is more complex - sugar concentration suppresses enzyme activity, for instance. Braukaiser's tests suggest conversion is faster in a thin mash.

The best thing about mashing thin is that you're much less likely to wreck the wort by oversparging.

[Aleman]

Actually the science behind the theory is quite sound . . . unfortunately on our scale there are a large number of other variables having a much greater impact on the body of a beer, that mash thickness doesn't have all that much of an impact . . . unless you go to serious extremes, and then it becomes impossible to stir and mix (< 1L/Kg). Even if you look at say Pilsner Urquell it's a pretty full bodied beer (for the style ; ) ), but they use (or used to use) up to 6L/kg with their decoction mashes.

I used to use 2.5L/Kg religiously as that was what was quoted in Grahams Books (and Dave Lines come to that), however over the last 10 years I'd now consider that to be a thick mash and normally use 3 to 3.5L/kg . . . Simply because it's easier to stir and to get a uniform temperature in the mash.

+1 for Braukaiser much better online resource than Palmer

[Charles1968]

My last couple of pilsners were mashed at 6 litres per kg - it definitely makes sense to keep sparge volumes lower for lagers, though you have to be a bit more careful with water preparation as the large water volume will overwhelm the buffering capacity of the grist and push up pH.

I reckon a good rule of thumb for most beers is use at least 50% of the liquor in the mash.

[fisherman]

I use 2.5 to 1 for standard mashes just to try and be sure to keep ph down. If I was starting again I would advise anyone to try batch sparging . I used to fly sparge and I have a great system but batch sparging seems to leave a sweeter wort.

[Jocky]

Braukaiser does show that the mash pH affects fermentability of wort - outside of 5.1-5.5ish the attenuation drops off, but the yield is better on the lower side.

Given that the mash thickness idea probably comes before the days of brewing when everyone was adjusting their water chemistry, I'd theorise that it was simply observed that a thicker mash meant a bigger bodied end beer, but could be sparged more than a thin mash, without anyone knowing it was to do with the pH.

[Charles1968]

Braukaiser does show that the mash pH affects fermentability of wort - outside of 5.1-5.5ish the attenuation drops off, but the yield is better on the lower side.

Given that the mash thickness idea probably comes before the days of brewing when everyone was adjusting their water chemistry, I'd theorise that it was simply observed that a thicker mash meant a bigger bodied end beer, but could be sparged more than a thin mash, without anyone knowing it was to do with the pH.

Good point. A thick mash will usually have the right pH without water treatment, so it helps with efficiency. You need to have good water to mash thin.

[data790]

Far too many people to thank individually but I thank you all.

I live in Norway and consider this the best water (without testing or doing any online research). However, It appears the takeaway message from this is not to sparge. Is this correct? What I have done in the past is says used 16 l mash for around 5.5 kg grain, collect about 10-13 l and then just dunk 10 l water to get a final 23 l pre-boil. This was the beer that came out rather watery. Perhaps a trial and error for this one is required.

Out of interest, I plan to make a belgian brown beir in the three weeks. Does anyone have a good recipie for a high strength, full-bodied and low bitterness Belgian that I can use and plan a better mash?

One more question, should the wort come out at the incorrect pH, how can this be adjusted? What method do folks use for this?

I have been brewing a while but just now getting into the meat of the hobby.

Thanks again

[fisherman]

I know nothing about your water but have you tested the alkalinity with a Salifert test kit from e-bay.

[data790]

I know nothing about your water but have you tested the alkalinity with a Salifert test kit from e-bay.

This I have not. I suspect the homebrew store has this in stock so I can have a butchers at it. Thanks for the advice

[fisherman]

Alkalinity is a very important part of brewing my own water alkalinity is normally between 85 ppm and 120 ppm I like to lower this between 20 and 25 ppm so I use carbonate reducing solution.if you go online to YouTube you will find lots of information regarding alkalinity showing you how to read it and how to lower it.also if you look on the Brew packs website at information a lot of water information is there.

[data790]

Alkalinity is a very important part of brewing my own water alkalinity is normally between 85 ppm and 120 ppm I like to lower this between 20 and 25 ppm so I use carbonate reducing solution.if you go online to YouTube you will find lots of information regarding alkalinity showing you how to read it and how to lower it.also if you look on the Brew packs website at information a lot of water information is there.

This is good information thank you again.