CNYBrew.com: Beer Geeks Anonymous

Wednesday, November 14, 2007

Beer Geeks Anonymous

[CNYBrew] Hi, my name is Travis and I am a beer geek

[Beer Blogosphere]Hi Travis


OK, so the first step is admitting so here I am, giving myself up.

So a while back I decided I wanted to start treating my mash for pH and taking measurements. I started to, but felt like I was not really doing anything and have since fallen off the wagon.

Now despite an outstanding explanation by Ted on pH and mash, it didn't get through my thick skull so I bailed. Today though, I woke up on a mission. I wanted to understand how and why I wanted to treat my water.

So I took a look at Ted's entry one more time, I listened to a podcast James with an interview by John Palmer on pH which he also covers in greater detail in the links I have associated with his name. I also looked back at an email I exchanged with James from Basic Brewing Radio. After all of that beer geekeyness, this is where I am:

First off, a brief overview of what is going on and why it's good to treat your mash; different regions have different water chemistry. John Palmer uses the Pilsen and Dublin regions as examples of two different water profiles. In Dublin, where stout is king, they have a highly alkaline water source.

A stout uses a lot of very dark grains that are acidic and help to counterbalance the natural alkaline water. Why are dark grains acidic? Who knows, they just are. With that said, every grain has a relative acidity or alkaline value that will contribute to the pH of the mash so a recipe combined with your water's profile will create the pH of the mash.

According to Palmer, you want to be at 5.4 to 5.8 mash pH at room temp, 5.1-5.5 mash pH at mash temp in order for optimum beta amylase conversion into fermentable sugars, thus your efficiency suffers. If the pH falls a half pH value, 5.4 at room temp to 4.9, beta amylase activity, conversion will suffer.

Brewing a stout, in water that is acidic, with the dark malts that are very acidic, it will effect your efficiency. The sugars in the wort will not be as fermentable because the pH was not in the correct range for beta amylase conversion. Also, in some cases the stout will take on a very acrid taste.

With all of that said, the long and short is that one reason for pH monitoring and adjustment is efficiency.

The second reason for pH tracking and treatment is based on the concept that the beer pH follows the mash pH. Why is that important?

Well the second example of the Pilsen region which has a much more acidic water profile, adding the grain profile of something like a stout would give you a low pH reading. This will cause you to get very dull flavor, soapy tastes, or tannin extraction depending on how high the pH is, however, it does not sound like your efficiency will be adversely effected by this.

So now that we have established that there is a reason to treat your wart and to track your pH, what do you do?

First off, get your local water report. In this there are three main parts to watch out for; calcium, magnesium, and bicarbonate concentration. I will use my Syracuse water as an example of what you are looking for:

Ontario - Calcium 31, Magnesium n/a, Sodium 17, Sulfate 27, Chloride 27, Bicarbonate n/a
Otisco - Calcium 42, Magnesium 11, Sodium 18, Sulfate 16, Chloride 36 , Bicarbonate n/a

According to the Water board, my water could be either one of these or a combination of the two. The important things to note on this is that there is moderate calcium, low magnesium and no bicarbonate. This profile would complement a pale ale pretty well. For a stout though, I am going to want to add some things to make the water more alkaline.

So now the question is what to add and how much of it do I add?

There are several additives that you can add to your mash to help balance your pH for the style brew that you are making. All of this info is available in MUCH greater detail on John Palmer's site, this is just what I took away from it.

Gypsum or Calcium- pretty universal additive for most water's -this will lower your PH

Calcium Carbonate - though there is calcium in this, the carbonate wins out and the net effect is raising your PH

Acids - They will lower the PH of your your wort-
Sulfate is supposed to be really good, but be aware of sulfate is corrosive and dangerous.
Hydrochloric Acid is good because you can get it at a pool store and most people are accustomed to using it.

OK, almost there. We have established that we want to balance the pH of the wort and we know what things other people put into their wort to achieve this balance, the question is now, how do I know how much of which stuff to put into my wort?

Well based on what I got from John's interview with James, the way to determine how much of any of the adjuncts you will need to calculate the residual alkalinity by taking the total alkalinity and subtract your effective hardness. So from here you will take the calcium concentration and divide by 3.5, magnesium concentration and divide it by 7. From here you take that quantity of effective hardness and subtract that from the alkalinity and this is your residual alkalinity.

Now I am not going to lie, I don't understand the last paragraph that I just wrote. This was based on the notes I took during the interview with John Palmer and it's a little above my pay grade.

So in a more practical sense, you can use one of the Excel spreadsheets from the links listed below that I got from Palmers website. You just punch in your amounts and it will adjust your wort accordingly. listed below that are all of the water profiles for some of the notable brew cities.

John Palmer's Excel spread sheet that makes all these calculations for you here and in metric here.

Water chemistry of classic brewing cities

Pilsen - Calcium 7, Magnesium 2, Sodium 2, Chloride 5, Sulfate 5, Alkalinity 14
Dortmund - Calcium 225, Magnesium 40, Sodium 60, Chloride 60, Sulfate 120, Alkalinity 180
Munich - Calcium 75, Magnesium 18, Sodium, 7, Chloride 10, Sulfate 10, Alkalinity 152
Vienna - Calcium 200, Magnesium 60, Sodium 8, Chloride 12, Sulfate 125, Alkalinity 120
London - Calcium 52, Magnesium 16, Sodium 99, Chloride 60, Sulfate 77, Alkalinity 156
Burton - Calcium 268, Magnesium 62, Sodium 54, Chloride 36, Sulfate 638, Alkalinity 200
Dublin - Calcium 118 , Magnesium 4, Sodium 12, Chloride 19, Sulfate 54, Alkalinity 319

Please keep in mind (assuming you took the time to read all of this) that this is my understanding of pH and it's relation to the brew process. I welcome any input from folks that know more than me (Ted I am looking in your direction) so please feel free to provide feedback.

Cheers!

3 comments:

Adam said...

Again...well done. Don't see too much blogging on this topic from I can tell.

Cheers!

grove said...

Nice posting.

Note that if you add dark malts to Pilsen water you'll end up with a *low* pH.

I agree there is very little blogging done on this topic. Personally I've been in denial wrt water treatment as it has been much like rocket science to me. Anyway, I'm getting closer to actually understanding this stuff, so I'll put up some experiments in the next few brews to see if adjusting the water helps anything.

The water here in Oslo, Norway, is extremely neutral. It is even softer than Pilsen water(!). This is convenient as it is perfect brewing water, and it is very good for making pale beers. Dark beers is another matter as you'll have to add carbonates to the water to raise the pH. Several of the stouts I've made have been sharp and acrid. The last porter I made was much softer and mellow as I added quite a bit of calcium carbonate.

Another two aspects that are worth mentioning are:

1. that you can use sulphates to accentuate dryness and hop bitterness.
2. that you can use chlorides to enhance fullness and maltiness.

Travis said...

Great stuff! I am glad everyone appreciates the post as I spent like 2 days writing it.

Good call on my reversing of the pH scale, science class was not something I paid attention in.

That's some interesting practical input on using adjuncts to contribute to flavor. One thing I noticed in my reading was that most people did not get into the practical application of pH and your wort, like taste and how an adjunct can contribute to a flavor.

I am looking forward to your experiments. I am interested to see how it's going to make a difference with my stout and it's efficiency.

Cheers.