Mash Efficency

[tomc]

Hello,

I'm a few brews into the extract method and was wondering what the collective knowledge is for adding grains to their extract brews.

Currently I'm getting my boiler up to 68C, then chucking the grains in along with the DME (as per Graham Wheeler's extract method). I give this a good stir, then put the boiler back on. The grains are left in during the whole boil (Graham's method).

However, on brews with 15-20% grain, I seem to be missing the "BeerEngine" expected OG by about 5 points. Playing with the numbers, this equates to a mash efficiency of only 50%. Is this to be expected with this method? If so, what can I do to increase sugar extraction - other than chucking more grain in!

Here's my most recent BeerSmith brew recipe as an example:

Dried Malt Extract 1600 grams 82.1%
Crystal Malt 300 grams 11.8%
Caramalt 160 grams 6.1%

Fuggle 90 mins 19 grams 39.7%
Golding 90 mins 17 grams 34.9%
Fuggle 10 mins 12 grams 25.4%

Final Volume: 15 Litres
Original Gravity: 1.045
Final Gravity: 1.011
Alcohol Content: 4.4% ABV
Total Liquor: 21.4 Litres
Mash Liquor: 1.2 Litres
Mash Efficiency: 100 %
Bitterness: 35.7 EBU
Colour: 40 EBC

I nailed the volumes, spot on but the OG came out at only 1.040, so the beer will be a bit weaker than I wanted.

[Jocky]

You won't be getting any sugar from those particular grains because they need to be mashed with a base grain (pale malt) to convert their starches to sugar. This will almost certainly be what is causing you to miss your gravity.

Crystal malt adds colour and some flavour to a brew when steeped, but doesn't have the diastatic power (enzymes) required to turn their starches to sugar.

I don't use beer engine, but I expect it will have a way for you to mark your recipe as extract, and that you are only steeping the grain.

The other thing I was going to mention - leaving the grain in during the boil??? Never boil grain - you will extract bitter tannins and make your beer not very nice to drink. Steep your grain at 65-70 degrees for half an hour, then remove the bag, drain, and get on with your boil. I've heard of people steeping grain while getting water up to the boil, but even they remove the grain before the boil is reached, and in my opinion that technique is a very easy shortcut to ruining your beer.

[jimp2003]

You won't be getting any sugar from those particular grains because they need to be mashed with a base grain (pale malt) to convert their starches to sugar. This will almost certainly be what is causing you to miss your gravity.

Crystal malt adds colour and some flavour to a brew when steeped, but doesn't have the diastatic power (enzymes) required to turn their starches to sugar.

I thought that with crystal/caramel malts (and others such as roasted grains) you don't need to mash them because the starch has been converted in the malting process....

THIS resources seems to say this is the case.

[Jocky]

Yes, my original post is not entirely correct, crystal will yield some sugar from steeping, but it will yield more if you mash them with a base malt, as not all of the sugar is converted during the kilning process.

An experiment was done on it by another home brew forum member: http://beertech.blogspot.co.uk/2011/03/ ... ation.html (worth a read)

Not sure if it would cause a 5 point drop in OG, but it would put a dent in it.

Additionally I wonder whether the tom's brewing software is expecting the crystal to be mashed for 60 minutes - which would mean a 30 minute steep, most of which is not in the mashing range of temperatures may cause less sugar to be extracted than predicted.

For me, I expect crystal to add pretty much nothing sugar wise to my brews, although I'm also heavily reliant upon brewing software to figure this stuff out for me.

[jimp2003]

Nice link Jocky thanks!

I was also wondering if the calculations might have gone astray somewhere in brewing software.

With regard to the grains I think you are right that in a mash there might be a little bit extra that can be recovered from crystal malts by the enzymes from the base malts.