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Help with Countertop Partial Mashing. Target OG too high.

J

jcole

Hello,

I brewed a dry stout recipe yesterday based on a modified Partial Mash recipe from my LHBS.  The original PM recipe was my second home brew and had turned out nicely.  However, it was a little on the strong side in terms of ABV (approx 5.3% - 5.4%), as I was hoping for more of a session dry stout at around 4.2%.   

So I set the recipe up in BeerSmith and reduced the Dark LME from 5 lbs. to 3.5 lbs. which got it down to around 4.3% ABV in the software's calculations.

Another objective in brewing yesterday was to get more comfortable with 'Countertop Partial Mashing' as described in the following article: BYO - Countertop Partial Mashing.  For this I used a 2 gallon beverage cooler for mashing as described in the article.

I created a brew sheet with all of this in mind and followed the instructions as carefully as possible along with those described in the "Countertop Partial Mashing' article.

One deviation from the brew sheet I should note is that after drawing the first and second wort, I sparged with 2 separate 5 quart infusions of 168 F water (instead of the the 4.67 gal of 168 F as indicated on the brew sheet). 

So, here is what happened.  Everything seemed to go well and I appeared to be getting a lot of extraction from the grains (probably a lot more than I did before when I brewed the original recipe from the LHBS which called for just soaking the grains in 155 F water for 45 min.).

I added the 3.5 lbs. of Dark Liquid Malt Extract at the end (15 min.) of the boil as described in the brew sheet and article, but ended up with an OG reading of over 1.070 instead of the expected 1.044 as stated on the brew sheet. 

I was pretty surprised and was concerned with such a high OG in terms of fermentability and ABV.  I wasn't sure what to do to salvage the brew, so I made an on the spot decision to remove enough of the wort, diluting with filtered water to get the OG down into the desired range.

I'm not sure whether this was the right thing to do or not and what the possible repercussions of it would be, but I didn't want a stalled fermentation or a dry stout with over 7% ABV.

Looking back now, I think that the Counter Top Partial mashing approach was probably much more effective at extracting the sugars etc. than what the instructions in the original recipe would result in.

So, I have a lot of questions now:

Should I have reduced the amount of LME in the recipe even further down from the original 5 lbs. that was called for?  Ie. 2lbs. instead of the 3.5 lbs. that I used?

Why didn't BeerSmith report a higher estimated OG based on these ingredients?  Is it because of the Countertop Partial Mashing method?  If so, how do I account for that in the software?  And is that method even necessary with a recipe like this?

What is going to happen to my beer?  What are the ramifications of diluting the wort the way I did? 

Is there anything else I could have or should have done different with the recipe or mash method?

Any input would be much appreciated.  I'm feeling pretty bummed about messing this one up and want to learn from any mistakes.

Thanks,
John
 
John,

What I would do is when you get done mashing.  Cool your down what you got and take a reading.  Then try to adjust your brew sheet to what you actually have.  After that you can figure out how much DME or LME to add to get you to the OG that you desire.  But if I was you I would be happy with how efficient you have been as long as you are not getting a bunch of unfermentables from have too warm of sparge water or something obvious like that.
 
ml2brew said:
What I would do is when you get done mashing.  Cool your down what you got and take a reading.  Then try to adjust your brew sheet to what you actually have.  After that you can figure out how much DME or LME to add to get you to the OG that you desire.  But if I was you I would be happy with how efficient you have been as long as you are not getting a bunch of unfermentables from have too warm of sparge water or something obvious like that.

Ok.  Thanks for the input.

Just so I'm clear on the details of what you are saying... Cool my mashed wort down to 60 F and then get a reading.  Then adjust the OG amount in BeerSmith?  And based on that add the appropriate LME for the target OG?

John
 
If you can figure out what your OG is supposed to be before you add your LME you will be able to adjust your brew house efficiency %.  Then you can adjust the amount of extract you may need to add to reach your desired OG.  I have done this with an imperial stout that I made but I had the opposite problem that you had.  I was not too great at with my efficiency and ended up too low.  I have done this by opening a new recipe and just putting in my grains and amount to see where my gravity is before adding extracts.  It seems like a lot of work but it has got me through.  Once you get more consistent in your sparging you will have less trouble.  At least I have.
 
I'm planning on brewing this one again tomorrow.  Although a good learning experience, I'm not very confident in yesterday's batch and don't want to wait 7 weeks before I have the desired beer in hand. :)

At this point I'm planning on keeping the the same items and amounts in the recipe, but simplifying the mash/sparge profile to more closely follow the method described in the following thread: http://www.homebrewtalk.com/f39/easy-partial-mash-brewing-pics-75231/

I've modified the mash profile in BeerSmith to align as much as possible with the steps outlined in the above article: http://www.metatractor.com/files/recipes/johns_dry_stout2.pdf

A couple of notes:

I'll be adding the LME at the end of the boil.

I couldn't figure out in BeerSmith how customize the following sparge step: "Sparge with 3.66 gal of 168.0 F water."

Based on DeathBrewer's method, it looks like he is using the same amount of water for sparging as he did mashing. In my case, about 4.5 qts. of 168 F water.

I also thought the following item on the brew sheet was interesting in light of the issue I had with the OG yesterday: "Add water to achieve boil volume of 4.08 gal. Estimated Pre-boil Gravity is: 1.057 SG with all grains/extracts added"

So, that's 1.057 SG on 4.08 gallons, BEFORE the 3.5 lbs. of extract is added. Adding another gallon to top it off to 5 gallons will obviously dilute it, but will dilute it enough to bring it down to 1.044 after the 3.5 lbs. of LME?

Thoughts?

Thanks for all of the input.
 
Cool my mashed wort down to 60 F and then get a reading.

There are adjustments on the sheet that comes with the hydrometer.
For example the batch I started yesterday read 1.048 @ 85 and the chart said to add 0.003 so I wrote down 1.051.

Not that that helps with your original question, but related to that more people have problems not reaching their intended S.G. than overshooting it.
So keep doing what you're doing with the grain, and back off on the extract.

-John
 
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