Mash Efficiency / Conversion

What went wrong? Was this supposed to happen? Should I throw it out? What do I do now?

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TeamBeer
Posts: 2
Joined: Fri Dec 29, 2000 12:42 pm

Mash Efficiency / Conversion

Post by TeamBeer »

Here is the question, I was happily mashing along at 152 degrees for one hour. Checked for conversion with iodine tincture looked good also tasted sweet. 11 lbs total grain, but came up short on my target O.G. range( 1.044 looking for 1.052 range ). Any ideas as to why this was or what could have effected ? Mash temp remained constant, sparged for 45 mins, after boil did get 5 gals.
dartedplus
Strong Ale
Strong Ale
Posts: 339
Joined: Sat Mar 17, 2001 11:33 pm
Location: Hummelstown, PA, US

Sounds familiar...

Post by dartedplus »

That sunds like the problems that I am having. Think it might be the PH?? I am pretty sure that my pH is too high, although I know that I can add some gypsum, I dont currently have any and forgot to grab some before I brewed on Sunday. What is the correct pH to start at?? Any help would be appreciated.
Sven
Light Lager
Light Lager
Posts: 30
Joined: Thu Mar 22, 2001 3:08 pm
Location: Lancaster, CA, US

pH phun

Post by Sven »

This is an invaluable resource.
http://www.howtobrew.com/section3/chapter15.html
John goes into great detail on the subject, but a good "all-around" number is pH of 5.3
I recommend reading Chapter 14 as well, if not the entire webpage.
BillyBock
Imperial Stout
Imperial Stout
Posts: 561
Joined: Sun Dec 31, 2000 11:37 am
Location: Ohio

Some Tips (SBT #4?)

Post by BillyBock »

I guess this tip would actually classify as Secret Brewing Tip #4: Keep some pale DME handy. This way if you get a lower extraction rate from your mash than planned, you can add some DME and bring it up. No one but you will ever know :-)
One area to look at for low extraction is pH. I assume you used well modified pale malt. Did your recipe have any dark grains or just pale malt? The dark grains will help naturally adjust pH. Do you have any lactic or phosphoric acid? We have hard water where I live with a lot of alkaline buffering power--it's pH is usually 9.3! To counteract this, I acidify the mash liquor to pH=7 with lactic acid before adding the grist--most times the mash pH falls in the target range of 5.2 to 5.5. Because of the hard water, I'm wary of adjusting water chemistry with salts appreciably. If I do make additions to the mash it's usually calcium chloride instead of gypsum. As far as the sparge liquor, it gets acidified to pH=5.7. This prevents tannin extraction from the husks later (see Mesa's earlier post). Since I've been doing this, that barely perceptible bitter harshness has gone away (which I attributed to tannins) and my extraction has always been 85%-90%. If you don't adjust the sparge liquor, you'll need to check the pH of your runoff and stop collecting wort before you start leaching tannins--that sounds like a monstrous pain in the a** to me, I find it easier to just acidify the water and get on with the day. You could also add the acid directly to the mash a drop at a time, make sure you stir it good because it'll burn any grains it contacts.
Another possibility for low extraction is incomplete conversion, even though the iodine test told you otherwise (it's not an exact science). I hold my mashes for 90 minutes to give the enzymes plenty of time to work.
--Cheers!
dartedplus
Strong Ale
Strong Ale
Posts: 339
Joined: Sat Mar 17, 2001 11:33 pm
Location: Hummelstown, PA, US

Thanks

Post by dartedplus »

I am pretty sure that the pH is my problem, I just needed some numbers to work with. Thanks!!!!!!!!
Ed
BillyBock
Imperial Stout
Imperial Stout
Posts: 561
Joined: Sun Dec 31, 2000 11:37 am
Location: Ohio

Forgot Another Culprit

Post by BillyBock »

I almost forgot another potential problem source--the coarseness of your milling. Overly coarse grist can cause low yield problem because of lack of access to the starches. So simply using a finer grist may help out considerably. Of course if it's too fine you'll end up with a gummy, flour mess. But then again, .25 to .5 lbs of rice hulls will prevent a stuck mash. BTW, is this your first mash and do you mill your own grains?
TeamBeer
Posts: 2
Joined: Fri Dec 29, 2000 12:42 pm

Not 1st beer

Post by TeamBeer »

Definitely not my first all grain beer. However first time with new water filtration system. PH has to be the the issue. Before I was using store bought water since my current water quality tastes like something out of a tin can and old water filter took way too long to get amount I needed. I may have misjudged the amount of gypsum and errored on the side of caution. As for the grist, since I don't mill my own I can't say. With no local brewshop I have grain milled when shipped. Note to self buy a grain mill. Thanks Billy
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