Adjusting Ph

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dicko

Boston Bay Brewery
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I have a question or two regarding PH of the water for mash and sparging.
I am using Eyre Peninsula tap water and I tested it with a pool testing strip and it is very alkaline.
I an lead to believe that the PH for the mash is important and so I want to get the water a little more acidic.

1. Do I have to adjust the PH of all the water used in the brew or do I just adjust the strike water for the mash, and sparge with the un-adjusted water?

2. If I make the water about 6 PH will this be too low (acidic) for a 1/2 pilsiner 1/2 ale malt grain bill?

3. Is there a formula or calculation for how much acid to add per litre with reference to the original PH?

Well that's three questions and any help or info will be appreciated :D

Cheers
 
Eyre Pen water is also very salty, I believe?

I definitely would not sparge with alkaline water!

As to the strike water, it is really the pH of the mash that is important, and mashes with darker malts in it tend to settle at a lower pH than all-pale mashes. I would at least acidfify the strike water to a pH of 7, maybe to 6 for all-pale beers. I use rainwater that apparently is slightly alkaline and I add 1 tsp malic acid to the strike water for all-pale mashes, the OG 1145 ale I brewed last Monday I did that treatment and had compete conversion at about 35 minutes into the mash and pretty good efficiency.

My eyes glaze over when reading the water sections of most brew books and I don't believe much of what I do read so I cannot help with formulas.

Jovial Monk
 
Hi Dicko

I use phosphoric acid to adjust the mash and sparge liquor. You really need a pH meter to do this properly.

I adjust my water to the low 6's and this is OK for sparging and gives me a mash in the required range (5.2 to 5.5).

If I have dark grains in the mash I adjust my strike water around 6.4 (they are more acidic)and you end up with about the right level in the mash.

You can use acidulated malt, but I have given up on that as it is hard to judge the correct amount - it is easier to use acid and not use as much as you need, then add a little more.

As JM says there a plenty of articles about adjusting water, but a lot of these are also altering the chemical balance (Ca, Mg, SO4) etc of the water. If you are only adjusting pH it is very easy.

Cheers
Pedro
 
Thanks Pedro and JM,
I was only using a swimming pool strip to test but I think my son has a phep 3 meter and I will get this to measure more accurately.

Pedro, how much acid would you add to say 40 litres of Adelaide tap water to achieve a PH around 6?

Cheers
 
dicko said:
how much acid would you add to say 40 litres of Adelaide tap water to achieve a PH around 6?
Dicko

Using 85% phosphoric, I think it is around the 3 or 4 ml mark, which is not a lot. I normally add some, check and then add a bit more if required.

You can buy the acid from Ace Chemicals on Meringue avenue, Nth Plympton if you are still in Adelaide. I think it is $25 for 500ml

Cheers
Pedro
 
Pedro said:
You can buy the acid from Ace Chemicals on Meringue avenue, Nth Plympton if you are still in Adelaide. I think it is $25 for 500ml
Crikey! - I will post a litre to you for that money (although it probably isn't something you are allowed to send through the post).

Now talking right outside my experience, I thought I read somewhere that if there is excess carbonates in the water, simply adding acid is insufficient, you need to precipitate out the carbonates (such as by boiling).
 
... it is really the pH of the mash that is important ...

Are you kidding! Here's me believing that the sparge water pH shouldn't rise above 5.8 else all hell will break loose. Sheesh, that's a relief.
 
pH of both the mash and the sparge are very important. With water as salt ladened as Adelaide's you can adjust the sparge with phosphoric or lactic acid to lower it to about 5.7 at "room temp" which will fall due to dissociation of the hydrogen ions as the temp rises.

At the end of the sparge the pH should still be below 6. This is not as important for batch sparging as for continuous sparging.

With a light coloured beer sparge pH should be kept below pH of 6. A lighter coloured beer with darker roasted grains should maintain the sparge pH within the above range. However if the pH of your town water is high these slightly acid grain may not keep the grain bed ph in the range you want and it is times such as these that acidifying the sparge is called for.

There is howver little point worrying about pH of the mash or the sparge without a means of accurately measuring it.

Don't just assume -- measure.

I routinely adjust my mash and sparge but I do it with a meter.

Now -- gypsum.

This is calcium sulphate and the calcium component is very important to assist the enzymes in the malt to reach the correct pH [See the recent very good explanation on correct mash pH on craft brewers by David Lamotte]

Acidification of the mash is primarily done by the enzyme phytase, which is active at 30 to 53C and breaks down insoluble phytin, a complex organic phosphate containing both calcium and magnesium, to phytic acid. Phytic acid has a strong affinity for calcium ions, and it forms calcium phosphate and releases hydrogen ions in the process. Inorganic malt phosphates also react with calcium to release hydrogen ions, but the phytic acid reaction is more efficient. When mashing, phytase activity is greater with under-modified malt than with highly modified malt. Highly modified malts have very little phytase because of the high kilning temperatures.

The nature of the mashing water has an important influence on mash reactions. The ions of major importance at mashing are those of calcium and carbonate, with magnesium and sodium ions playing lesser roles. Calcium lowers the pH of the mash mainly by its interaction with phosphates and to a lesser degree with protein from the malt. Carbonate ions operate in the reverse direction.

If the water of the mash has insufficient calcium it will not reach correct pH. If this occurs and it often does mash efficiency levels can suffer.

A beer with a high proportion of dark malts can become too acid [pH level too low] and this can be a rare time to add Calcium Carbonate to the mash. Calcium Carbonate is normally an insuluable salt in water but because of mash acidity a reaction takes place and the ph of the mash can be held in the correct range.

Due to the strange composition of Adelaide water gypsum is a good water salt to add and if you do, keep the ratio of Sulpates to Chlorides at [as close as you can] 2:1

eg ... 100/50 or 300/150

Refer to the Murhy's site for information on this ratio.

http://www.murphyandson.co.uk/brewing_articles.htm

Depending on the water I'm brewing with I use gypsum [Calcium Sulphate] and/or Calcium Chloride.

Calcium Chloride is not advisable to add to Adelaide water because of the rather high existing Chloride levels.

If you wish to structure a particular water profile you can guesstimate rain water as "reasonable" salt free [it isn't really] and adjust using a good set of scales and the following

Epson Salts -- Magnesium Sulphate [chemist]
Gypsum -- Calcium Sulphate
-- Calcium Chloride [Sometimes hard to find]
Chalk -- Calcium Carbonate
Table Salt -- Sodium Chloride [Must not be iodised -- harmful to yeast]
-- Sodium Bicarbonate [Strongly alkali]

These salts are all you need to achieve a good facsimile of any brewing water.

The "Calcium" rule for good mash efficiency is a minimum of 50ppm.

Don't attempt to gues salt weights. Weigh them and use BeerSmith or equivelant to help determine the salts to add. Doc mentioned a downloadable utility program for water chemistry that is very handy. Brewater3

You cannot accurately dump acid into the water you have and hope. A pH meter is not that costly. Then when you have one you can acid wash yeast as well.

The above applies to mash brewing because you have the ability to control your processes.

Steve
 
Wow!!
Thanks for that Chiller,
I know you briefly explained the rainwater bit when we last met, but seing it all in writing makes it a lot clearer.
I had a quick look at that site of Murphy's and there is a good nights reading in there.
( my wife is pleased :lol: another night fixed to a brew related subject on the computer :rolleyes: )
Looks like water adjustments are now on my brewing adgenda for 2005.

Like "Arnie" said, "I'll be back!"
Cheers
 
Chiller

I should add to my post above that I spent most of yesteday afternoon reading texts on brewing water from the four text books that I have and I will admit that JM was right in what he said that "your eyes glaze over after a while" when trying to understand these fundamentals that you have explained so easily.

Have you ever considered writing a book on brewing in a simple form that is easily understood explaining all the procedures in all grain which at times can seem daunting when reading texts from US based authors?

Cheers and once again "Thanks!"
 
Dicko

If you know your water profile you can use programs like Promash to work out additions of salts to make your water match that for a specific region. This is a lot easier than working off the formulae in books.

The pH adjustment is easy though, add acid, check, add etc etc

Cheers
Pedro
 
Do you know the sodium content of your water, dicko?

JM
 
JM

Dicko needs a full water profile (you can ask SA Water for one), not just the sodium content. The main thing you need for yeast health is calcium and most water suppplies have ample of this. The sulphates, chlorides and chlorine in the water have the most chance of being detrimental to the beer with our water.

Dicko, if you want help interpreting the SA Water data, then send it to me via PM and I will help.

Cheers
Pedro
 
Hi JM,
The water here comes down the pipline from Morgan the same as Whyalla.
I would imagine that it would be similar to Adelaide water.

Hi Batz,
I have only tested my water with a swimming pool strip.
The PH meter that I bought for our cleaning business cost me about $80.00 seven or eight years ago. We use it for the determining the PH of detergents for cleaning wool based carpets. Like most things, once you know the correct PH of the detergents you are using then you dont use it any more.
My son is dropping it off on thursday so I will post a pic of it and in the mean time I will try and remember where in Adelaide I bought it.

Hi Pedro,
Next time I am in Cleve I will go to the SA Water office and ask them for the figures. I will PM you with any queries.

Many thanks to everyone who has helped.

Cheers
 
Instead of conducting it over PMs, I vote for you to list the water report and interpretation here for all of us to learn. I don't see it as a huge tangent from the original thread topic and would be useful to a lot of us.
 
No probs NRB

We should post a summary as there is not really one correct answer to this.

Cheers
Pedro
 
Yep, no worries guys,
I wont get to Cleve until Friday ( damned work :angry: ) so it may be a week or so before I get the report.
Ill post it under this topic and we will go from there so at least others may assess the report if they wish.
Cheers
 
Hi forum fellows :D

Just letting you know that the water sample report that I require is harder to get than I first thought. ( Why wasn't I surprised )!!!
I contacted an SA Water representative and he told me that I had to send a sample to an independant laboratory. :eek:
When I politely suggested that, that was BS, he then gave me the name of a SA Water supervisor that regularly sends water for testing and could give me the results. :rolleyes:
Well, this guy is harder to track down than Ned Kelly but I will keep trying.

Cheers
 
I cant understand this Dicko. In WA, it only requires a simple phonecall to our local Water Authority and an appropriate report pops up un the computer next day. Why should it be difficult in your area. After all, I think everybody is entitled to know what they are drinking and not just take Big Brother's word for it.
 
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