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Old 01-25-2011, 10:46 PM   #51
funkswing
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5 grams Gypsum is more like 1 TBL, not 1 tsp. But I wouldn't measure like that, its well worth the $10 on ebay for Digi's.

OK, I weighed it out:

1 tsp gypsum = 3 g
1 TBL " " = 9 g
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Old 01-25-2011, 11:06 PM   #52
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I've gotten 4 grams when measuring on my digi scale for gypsum. Probably depends upon whether you're doing a rounded tsp or straight tsp. Still good to know what AJ's assumptions are for his water profile recommendations so we can all adjust accordingly with the EZ Calc or whatever program you're using.
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Old 01-25-2011, 11:13 PM   #53
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Calcium chloride is in nice little spheres which pack together pretty uniformly. Gypsum, by contrast, is fluffy so you will have variation according as to how tightly it is packed and how "level" the teaspoon is. Just sticking a teaspoon into the jar and dumping it onto the balance without much regard for leveling (but you certainly couldn't call it heaping) I got 6 grams. A carefully leveled teaspoonful from the same jar came in at 3.6 grams.

It really is better to weigh it out.

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Old 01-26-2011, 12:14 AM   #54
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Ajdelange,

Thanks for the response. I was able to calibrate my ph meter so, thankfully, I didn't mess that up! I guess I misunderstood the add 1 and double for hoppy beers...

I brew my IPA frequently so i will try again and scale back on my additions.

 
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Old 01-26-2011, 12:49 AM   #55
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Thanks aj. So for your water recommendations is it safe to say you are assuming 5 grams for gypsum?

Also, are you considering apa and ipa in the British category or minerally beers category for you recommendations?
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Old 01-26-2011, 07:29 AM   #56
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Looks like Kai has a new addition on his web site (at least I haven't seen it before) - an easy to visualize model of pH buffers:

http://braukaiser.com/wiki/index.php/A_simple_Model_for_pH_Buffers

Lots of other interesting info. over there, too.

 
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Old 01-31-2011, 01:08 PM   #57
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I'm just now getting to 'post-fermentation' with some of my beers since acquiring a pH meter and using this primer (although I haven't tasted any of them yet, a con of having a pipeline I guess). I've noticed that my post-fermentation pH is a little lower than expected. With a pre-fermentation pH of 5.45-ish I'm getting 4.2-ish after fermentation (using sauermalz in mash). There is a comment in one of Kai's pH articles about really soft water not having enough buffering ability so the yeast take the pH too low. I am using a high % of RO (80% up to 95% for yesterday's Boh Pils) because it seems I have to in order to get good pH without using a ton of sauermalz.

Is this anything to be concerned about (and is it normal)? Using mostly RO and sauermalz it seems I'm trying to decrease the buffering ability (so the sauermalz and roast/crystal malts can reduce pH enough) but then post-boil it appears that I may need more buffering ability. Would adding a very small amount of CaCO3 at the end of the boil help? Would it counter any sourness perception?

Lastly, is the ability to reduce pH during fermentation yeast strain dependant? Do certain strains do this better than others?
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Old 01-31-2011, 02:03 PM   #58
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Quote:
Originally Posted by SpanishCastleAle View Post
I'm just now getting to 'post-fermentation' with some of my beers since acquiring a pH meter and using this primer (although I haven't tasted any of them yet, a con of having a pipeline I guess). I've noticed that my post-fermentation pH is a little lower than expected. With a pre-fermentation pH of 5.45-ish I'm getting 4.2-ish after fermentation (using sauermalz in mash)...
Is this anything to be concerned about (and is it normal)?
Entirely normal and the sign of a healthy ferment. Most finished beer comes in between 4.2 and 4.8 with the lagers generally in the upper part of that range and the ales generally in the lower. Some ales and, of course, sour beers, will have pH less than 4.2. Lagers above 4.8 doubtless exist but I'd be concerned if pH got that high in one of mine.

Quote:
Originally Posted by SpanishCastleAle View Post
Using mostly RO and sauermalz it seems I'm trying to decrease the buffering ability (so the sauermalz and roast/crystal malts can reduce pH enough) but then post-boil it appears that I may need more buffering ability. Would adding a very small amount of CaCO3 at the end of the boil help? Would it counter any sourness perception?
Yes, the object in using low mineral water is to get rid of carbonate thus lowering the buffering capacity (alkalinity) of the water so that the lactic in the sauermalz can effect a pH shift but no, you don't need to replace that as your beer pH is falling in the right place. Now if it is a lager that is coming in at 4.2 we might scratch our heads a bit but there are those that would add acid to your kettle to get knockout pH down to 5 - 5.2. I'm not advocating that for now - wait until you taste the beers. Acid in the kettle might be something to try at a later date when fine tuning recipe/procedure.


Quote:
Originally Posted by SpanishCastleAle View Post
Lastly, is the ability to reduce pH during fermentation yeast strain dependant? Do certain strains do this better than others?
Yes. That is, I assume, why lagers tend to come in at pH higher than ales.

 
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Old 01-31-2011, 02:18 PM   #59
ajdelange
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Last brew day I took mash pH vs temperature measurements to try to verify the commonly published shift amounts. In a sample from the protein rest I found a shift of -0.0057 pH/C and from mashout, -0.0052. Averaging those would give -0.0055. I'm not advertising this number as any more than what it is - the number I got using RO water with Weyermann's floor malted Pils with some carafoam and sauermalz in one brew on one day.

Anyway calling room temperature 21C and assuming mash temperature of 65C (149F) the shift would be 0.242 which is a little lower than the 0.3 that is commonlu thown out so that 5.47 would map to 5.23.

 
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Old 01-31-2011, 02:20 PM   #60
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Quote:
Originally Posted by -TH- View Post
Is that 5.47 at room temp? Then the pH at mash temp would be what - say 5.3 ish?
That's a good question. I was assuming that I would be taking a reading at room temp and expecting 5.47. Is that correct?

 
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