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Messages - mabrungard

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All Grain Brewing / Re: Water treatment for stout
« on: July 09, 2011, 07:14:08 PM »
There are at least 2 ways to go.  1) Add minerals including an alkalinity increaser such as pickling lime to the mash water and mash the entire grain bill as normal.  2)  Add minerals only to bring the calcium up to a minimum concentration of about 40 to 50 ppm and mash only the base malts in this water.  Steep the crystal and roast malts separately and add their steeping liquid to the boil.  This takes the really acidic grains out of the mash and allows you to avoid the need for adding alkalinity.

General Homebrew Discussion / Re: factors contributing to diacytel
« on: July 08, 2011, 12:58:05 PM »
High fermentation temperature is less likely to cause diacetyl production.  Prematurely dropping your fermentation temperature before the yeast have reassimilated the diacetyl is a much more likely cause.

Interesting link to the resource.  I have seen other references to calcium helping to stabilize the alpha amalyse (Malting & Brewing Science)(The Biotechnology of Malting and Brewing).  Unfortunately, even the reference at the link above does not cite a minimum calcium concentration.  The other references don't either.  

Calcium is precipitated in varying degrees through a variety of reactions.  From my research, the amount of precipitation is proportional to the calcium concentration up to about 110 ppm.  Beyond that point, the amount of precipitation is again proportional, but on a lesser slope.  This has no bearing on the minimum level, but it has a significant impact on the concept of Residual Alkalinity.  That will have to wait for another day.  

Regarding the minimum calcium concentration, there does not seem to be a good reference with respect to alpha amalyse performance, yeast health and flocculation performance, or oxalate precipitation performance.  We know that malt contains some calcium and it can be somewhat liberated in the mash (especially decoction).  I don't know what the minimum calcium concentration should be, but I think the evidence suggests that its in the 40 to 50 ppm range.

All Grain Brewing / Re: Small Batch Test Brewing
« on: July 05, 2011, 11:48:24 AM »
A serious problem I see with really small batches is that the need for precision in measuring grain, hops, and yeast increases.  You can probably get by with a measurement precision of a gram or so with a 5 gal or larger batch, but that needs to be finer when you're only dealing with a few pounds of grain or grams of hops. 

All Grain Brewing / Mash Average Diastatic Rating vs. Mashing Time
« on: July 04, 2011, 01:53:23 PM »
We had an interesting discussion on mashing time last fall, but it did not cover mashing time vs. diastatic power.  I bring this up after reading a bit about low diastatic mashes requiring more conversion time in Strong's 'Brewing Better Beer'.

In the discussion of Ingredients (pg 108), Gordon mentions that mashes with lower diastatic power may require more time to convert.  Intuitively it makes sense, but I had not heard it before.  The general concensus is that the average diastatic rating of the mash needs to be at least 30 to 40 Lintner to provide complete conversion.  I'm more inclined to believe its 35 to 40 Lintner minimum based on Gordon's information.

Given Gordon's statement and the fact that base grains are easily over 100 Lintner, is there really a difference in the time to a negative iodine reading with respect to the average Lintner rating of the grist?  I did a brief search, but do not find guidance from anyone having performed such a study.  Clearly, a grist with its average diastatic rating
above 100 Lintner will have plenty of enzymatic power to convert, but is it going to convert faster than a grist with 35 Lintner?

Another curiousity is how the average diastatic power is calculated.  Since diastatic power is only needed to convert starches, is there any reason to include the weight of grains such as crystal malts in the calculation of the average diastatic rating for the grist?  Dilution by those grains is one thought, but I'm not sure its valid.  I'm thinking that the total sum of diastatic power divided by only the total weight of STARCHY grain and adjuncts might be valid.  This is in contrast to the total diastatic power divided by the total grain and adjunct weight.

Yes as Denny says, don't bother with transferring to another vessel.  This is especially true if you can keep the vessel and the beer cool.  That reduces the chance of autolysis of the yeast trub in the fermenter. 

Unless you're actually adding another yeast, bacteria, or other fermentables, there is no such thing as a secondary fermentor.  Its a clarifier.  Your primary fermenter is equally suited to serving as a clarifier.  Temperature control is an important caveat.  Keep it cool, (preferably cold) in order to reduce the time it takes to clarify the beer and reduce autolysis risk.

Yeast and Fermentation / Re: UNDERPITCHING, Could it be desirable
« on: June 24, 2011, 11:08:54 AM »
Underpitching is an important factor when brewing Weizens.  It accentuates ester formation.  For Belgian strains, its debatable if it would be desirable.  Wit, maybe.  Others might be over the top. 

Given that the OP is creating a Session gravity and the potential for excessive fermentation byproducts is reduced, then I think it might be a feasible experiment. 

That is a great looking water report.  The alkalinity is nicely low.  Hardness is low, but that does not matter.

Given the low alkalinity, I would not be surprised if the mash pH fell into range if the OP was performing a normal mash procedure. Even for lighter colored beer grists.  But since the OP says he does the full volume of water when mashing BIAB, it is possible that there isn't enough acidity in light colored grists to bring the mash pH down.  Bru'n Water allows you to check that out.  It also allows you to check if that 2% amount of acid malt is enough to do the trick for the pH.  

Given that the OP says his darker beers seem fine and the lighter ones not so much, it is probably the resulting mash pH that is creating the problem.  

BIAB is a nice method, but the high amount of water in the mashing step can accentuate the amount of alkalinity in the mash.  On the other hand, given the relatively low alkalinity of this water, if the OP was mashing with a normal water to grist ratio, the mash pH would probably fall too far when brewing dark beers.  

Check out Bru'n Water.  It is the perfect tool for situations like this.

Equipment and Software / Re: Conical bottom dump valve issue and ?
« on: June 23, 2011, 05:47:16 AM »
What about putting the valve in boiling water for a few minutes to drive off any oils.  You would have to adjust the valve position a few times, but I'd bet that you would get most available oils off the valve with that procedure.

All Grain Brewing / Re: Mash out questions
« on: June 23, 2011, 05:44:35 AM »

That is a very good point, mashing out is providing an additional heat input that we'll need eventually to boil.  Mash out just makes sense to me.

Equipment and Software / Re: Extending the life of Star-San
« on: June 21, 2011, 05:38:11 AM »
I'm betting that its the complexing of hardness ions that's causing the problems since at a pH of 3 and less, there is very little alkalinity (technically there is no methyl orange alkalinity since the pH is below 4.3).  

I just started a test using my house's softened water that I know runs about 2 or 3 ppm Ca and Mg.  That is as low as my RO system puts out.  The softened water still has high alkalinity since those ion exchange softeners do not alter alkalinity.  I'll see if it clouds up in a few days and report back.

Its been a couple of weeks now and the StarSan solution mixed up using my house's ion-exchange softened water is completely clear, just like the batch mixed up with RO water sitting next to it.  Both are sitting in open water glasses on my work bench.  Both were mixed to a starting pH of about 2.  

I'd say that using water softener water for StarSan is one of the few uses that salt-based softened water has.  It looks like the clouding effect is due to the hardness ions in the water. 


Yeast and Fermentation / Re: Swamp cooler duration
« on: June 21, 2011, 05:31:00 AM »
The evaporative cooling effect of a swamp cooler only provides a couple of degrees.  If you're fermenting at 78F, it probably won't matter much with going up a few degrees.  The esters and fusels are likely to be present in large numbers either way.  A large improvement to your beer quality will come with more effective fermentation temperature control. 

The new edition (4th) of Kunze was just published in May.  Its available from Siebel for $200.  Decent price from what I can tell.

Ingredients / Re: Hop Shelf Life Adjustment?
« on: June 17, 2011, 09:37:09 AM »
First of all there is a solubility limit for alpha and iso-alpha acids in wort, and that is around 80 to 90 IBU.  So that might be a contributor. 

The other issue would be the SG of your beer. Since it was an IIPA, the gravity had to be high.  That further reduces the perception of bittering in my opinion.  That is the great thing about high gravity beers, no matter what the brewer does to increase their calculated bitterness, they typically still have modest bittering perception.

All Grain Brewing / Re: Mash out questions
« on: June 14, 2011, 12:43:32 PM »
I also use a RIMS and its easy to set my heater controller to ramp the mash temp up.  I consistently measure several points Brix increase in the wort gravity with the mashout heating and recirculation.  Since its not a big deal for my system, I always do it.

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