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Messages - mabrungard

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1096
All Grain Brewing / Re: Oxidation question
« on: May 28, 2011, 03:42:21 PM »
A friend of mine has a HERMS horizontal brew system with 2 pumps that produced a string of oddly but intensely oxidized beers.  It turned out that the pumps were oriented such that they were cavitating a lot during recirculation.  The problem was worse with darker beers.  Changing the orientation of the pumps fixed the problem ASFAIK.  That's the only example of HSA that I've ever tasted at club meetings.

Cavitation cannot create oxidation.  The bubbles are products of the intense vacuum created by the pump at cavitation condition.   There would have to be a leak that allows an external air source into the flow loop for the bubbles to create the oxidation effects.

1097
Equipment and Software / Re: In-line Oxygenation
« on: May 26, 2011, 04:59:26 AM »
Martin, Do you get oxidation from doing that?  For a while I left the oxygen on for the full transfer time and got really bad oxidation.  Now I just leave it on for a minute or 2 (per 5 gallons) and it seems to ferment well.

I would like to do the 25' transfer hose too.  I brew out back and then have to carry the fermenter down my 100 year old stairs to the basement.  How do you take care of it?  Do you take it apart after each brew?  It sounds like it is on the cold side.  How do you sanitize it beforehand?

TIA, Tom

I use a very low flow rate and do not pick up any oxidation notes in my finished beers.  As I said, my oxygen usage is very low.

That tube is on the cold side and it requires some care to avoid contamination problems.  Of course, the tubing is drained fully after each use.  I always recirculate either Starsan or Iodophor through the full pump/tubing/plate chiller/oxygen system prior to each wort transfer.  And every few brews, I also go through a full hot PBW recirculation.  If I see any buildup in the tubing, I replace it.  But, the cleaning regime seems to be keeping things visably clean and I've replaced the tubing about 2 times in about 5 years.  

1098
Equipment and Software / Re: In-line Oxygenation
« on: May 25, 2011, 05:37:45 AM »
I use an in-line oxygenation system that is made with a 1/2 inch copper tee and a reducer that was further soldered closed so that I could drill it to fit the small oxygen tubing tightly without leaking.  There are reducers at each end of the wort flow path in the system to take the line diameter from 3/8 inch to 1/2 inch so that the sintered stone will fit within the system.   

I pump my wort through my Therminator plate chiller and then through the oxygenator on its way to my fermentor.  I use 25 ft of 3/8 inch tubing after the oxygenator to allow me to reach the fermentation chamber from my brewing location.  That 25 ft of tubing provides a long residence time for the oxygen contact, so I know my transfer coefficient is very high.  I literally trickle the oxygen through the sintered stone while the pump is flowing wide open.  I can see a definite stream of fine bubbles through the tubing.  I know my O2 flow rate is low since I can treat about 20 batches or more with a single red O2 tank.  I wish I had an O2 meter to check the effectiveness, but the only evidence I have is clean tasting beer and very active fermentation. 

1099
Yeast and Fermentation / Re: Dry substitute for WY1028
« on: May 23, 2011, 07:49:47 PM »
I really like the S-04.  One of my clubmates called the character, Bready.  But, its not too bready and has more character than S-05.  I just brewed up one of my favorite beers (with S-04) that I typically brew with 1028, so I'll have a direct comparison in about a week. 

1100
All Grain Brewing / Re: Tannins
« on: May 23, 2011, 07:44:32 PM »
pH is a factor, but only to the degree that it indicates that the water alkalinity is brought down.  Alkalinity is the real factor that is the concern in reducing tannin extraction along with temperature. 

For brewers that have brewing water with really low alkalinity, they don't really need to adjust the sparge water pH.  In addition, with a low alkalinity water, it would probably only take teeny amounts of acid to drop the pH anyhow.

1101
All Grain Brewing / Re: Bru'n Water Questions
« on: May 23, 2011, 07:32:43 PM »
If you're using a low calcium water that produces an acceptable mash pH without adjustment, then an enhancement that the wort will need is a dose of calcium to improve yeast performance.  Since adding calcium to the mash has the tendency to reduce mash pH, that calcium dose can be added directly to the kettle instead of the mash.

Yes, the calcium dose can be calculated using the kettle volume and the intended calcium concentration would be produced in the wort.  The question is what should that calcium (or any other ion) concentration be in the post-mash wort?  The mash has the tendency to add and subtract ions in comparison to the initial water concentrations.  Given that ambiguity, I recommend that a 'close enough' philosophy be used.  Just ignore the ionic gains or losses in the mash and add your desired ionic concentrations directly to the mash.

I too disagree with Gordon's lack of accuracy that results from adding dry minerals volumetrically instead of by weight, but the simplicity of his water adjustments would not penalize him too much.  And I can't argue with his results.  Plus, I understand he does use a pH meter to check his mash pH.  And as mentioned above, the ability to consistently reproduce a given outcome and assess minor changes will come to those who brew a similar beer time after time and dial in all components of a beer.  Gordon rebrews and tweaks with great effectiveness.

Unfortunately, that is not how most brewers brew.  I do enjoy brewing certain beers over and over.  I do tweak with each sucessive batch, but I also want a tool that is going to help me get in the ballpark the first time and subsequent brews.  Gordon properly coaches for brewers to not mess with their water too much.  Since he typically brews with RO water and the RO process is 'messing with your water to the max', what he really should be telling brewers is, 'don't add too much mineral content to your brewing water'.  Brewing with RO or distilled water is a luxury that some brewers don't have access to.  Using a program like Bru'n Water is an important step in understanding what your water is and what the effect of adding minerals will be.  Unless a brewer is using RO water like Gordon does, the water adjustments he uses could be disasterous to your brewing.  

With all that said, I too use RO water for my brewing since my tap water is not suitable for brewing.  As RichardT suggests, if you're using RO or distilled water, you can skip Sheets 1 and 2 in Bru'n Water.  You just dial up the dilution percentage to 100% and figure out your desired mineral additions.  And since distilled water and RO water have very low alkalinity, it is not necessary to acidify your sparge water.  Sparge water pH is NOT the real criteria we need to concern ourselves with, its reducing the water alkalinity to low concentration that is the real concern.  

As RichardT finds with his Weizenbock, brewing with RO water has its limitations as the grist color increases.  A source of alkalinity is needed to keep the mash pH from dropping too low.  I put that red pH signal to relay the findings that I've experienced.  The mash pH is very non-linear as the pH drops into the very low 5 range.  The mash has to have a really high net acidity to drop the pH that low.  Its my experience that a beer mashed at that pH is overly tart and rough.  Even a 5.2 is really too low for my taste.

I agree that the Munich profile is a bit much for many of the lighter styles that have been produced in Munich, but it is well suited to the dark styles.  To brew those lighter styles, the boiled Munich profile is much more appropriate.

All great questions!  And yes, pickling lime is quite powerful.  Don't even think of using it unless you have a good scale and also tend to underdose it instead of overdose.
 

1102
yep, just look at is as .3 inherent error and .3 temp shift.  The .3's are in opposite directions so they cancel each other out.

Uh...I don't use the strips since I have a meter and the fact that they have proven to be inaccurate in the mash, but I don't think the temp shift enters into this issue.
 

1103
All Grain Brewing / Re: Advice for increasing body of india red ale
« on: May 16, 2011, 02:47:08 PM »
Adding a small percentage of either flaked wheat or barley would also increase the perception of body in the beer.  The balancing act is to avoid adding too much and producing a haze problem.

1104
General Homebrew Discussion / Re: Benefits of a 90 minute boil?
« on: May 16, 2011, 02:44:19 PM »
Ninety minutes produces about the maximum isomerization potential for alpha acids in wort according to work by Malawicki and Shellhammer.  Beyond that time, the isomerized alpha acids are broken down to a slight degree and the bittering actually decreases.  In terms of energy efficiency of converting alpha acids to iso-alpha acids, a boil time in the 60 minute range is better than 90 minutes. 

1105
Equipment and Software / Re: Finally got to try my new pH meter
« on: May 15, 2011, 02:38:46 PM »
Its just the thermal thing that shortens the life of the very thin glass bulb.  Going from your room-temperature to the mash temperature several times, places a lot of thermal stress on that bulb.  If you're a heat lover and run your room temperature around the 150F range, then it should be no problem to measure the pH directly in the mash.  For anyone else, cooling the wort sample to a more reasonable room temperature is going to stress the bulb less.
 

1106
All Grain Brewing / Re: Why won't this beer clear?
« on: May 14, 2011, 06:11:03 AM »
As for using acids to adjust your pH, generally 1-3 tablespoons of food grade lactic or phosphoric acid per 5 gallons of water will do it, based on mineral profile of your water and grist. Take a sample of your cold brewing liquor, carefully add your acid drop by drop (and eye dropper works well, figure about 1 ml per drop) and test pH using good-quality pH strips or a pH tester as you go along. Since your mash pH will drop at conversion temperatures, subtract 0.4 pH to get your true mash pH. Once you've got your mash pH adjusted, you can convert units and scale up to apply the correct amount of acid to all your brewing liquor (mash and sparge). Don't sweat it too much, though, you just need to be in the ballpark - 5.2-5.6 pH.

I think it's much more critical to monitor pH during runoff. Anything above about 5.7 pH and you start getting tannins, which is a sure road to misery.

In a broad sense, Thomas' advice is sound since he is advocating testing as you add acid.  Its workable, but its not convenient or quick.  With alkalinity information on the brewing water, its easy to calculate exactly how much acid is required to bring either the mash or sparge water pH into proper range.  The only program I know of that brings this capability is Bru'n Water.  The statement that 1 to 3 tsp of lactic is suitable might be fine for Thomas' water, but cannot be applied to every brewer.  There will be some bad pH consequences with that advice.

Regarding the issue of astringency, a pH of 5.8 is just barely into the range the could promote tannin extraction.  On top of that sparge water temperature has a larger effect on tannin extraction than pH.  Maybe the sparge temp was well under 170F and that was not an issue?  In any case, the lack of percieved astringency is probably not a good indicator that pH was not a problem.

Regarding 5.2 Stabilizer again, it is quite effective at keeping the pH of water with low alkalinity from dropping too much when brewing with dark grists.  Unfortunately, that is not the brewing condition for a lot of brewers.  For those with elevated brewing water alkalinity and lighter grists, it is well proven to be ineffective.  A good brewer would avoid it at all cost.

1107
All Grain Brewing / Re: Why won't this beer clear?
« on: May 13, 2011, 01:47:29 PM »
I would not be surprised if the 5.2 Stabilizer addition was your problem.  It should actually be called 5.8 stabilizer since that is where both AJ Delange and Kai Troester have found that it tends to put the mash pH.  It is not a good addition to brewing and it also adds a substantial sodium content to your wort.  A 5.8 mash pH can cause problems. 

If your water is alkaline, you would be better served by learning to use acid for pH control. 

1108
Yeast and Fermentation / Re: Reusing a Wyeast American Wheat 1010
« on: May 13, 2011, 09:23:26 AM »
I find the limitation to racking onto an existing yeast cake is due to either roast, hopping, or spices in the previous brew since those components will carry over into subsequent brews.  If your honey wheat was non-descript with respect to those components (I expect that it was), then racking onto that yeast cake should be fine.
 

1109
Anything that you can do to reduce temperature and vibration stresses to the beer is a very good thing.  Its good that you're taking the beers to the competition personnally.  I judged Weizens at the Nationals in Las Vegas several years ago and was quite disappointed in the quality of the beers in the session.  There should have been no way that these beers were advanced to the second round if they were that poor.  It was clear to me that the shipping and handling adversely affected the quality and perception of the beers.  Its not like Las Vegas in early June is cool or anything.  I'm sure the trip that each of those beers took across the desert affected them severely.

1110
Equipment and Software / Re: Finally got to try my new pH meter
« on: May 12, 2011, 12:59:02 PM »
If you standardize to measuring your wort pH at room-temperature, then automatic temperature compensation becomes much less of an issue.  Brewers should not place their pH probe in the mash since it shortens the life of the probe.

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