Sunday, March 16, 2014

Brewing Water Demystified - Part I

In this first of a multipart part series on brewing water properties I explain the most basic information you'll ever need to know for making delicious tasting beer. In my view a brewing process consists primarily of three main parts. Each part of the process influences the taste and flavor of beer in their own unique way. Having the perfect recipe is the first part of the brewing process, it's where the grain bill selections and hop schedules are created. As the recipe evolves it influences the flavor of the wort during the mash when the grains soak in hot (147-158F) water. The wort produced by the mash is drawn off the grain bed then boiled for an hour or more. Hop and other kettle additions like fruit and spices in measured amounts can also be added to the wort creating even more complex flavors in the beer. Yeast has to get a mention too, the temperatures and strain used to ferment wort into beer also influences the flavor of beer.

We're primarily interested in the first part of the brewing process when selecting grains for a style of beer, its also a great time to adjust the brewing water properties. Different styles of beer come from different regions of the planet, knowing that can help when researching the water profile of any specific region on earth.

The Right Water Profile Produces Clear Flavorful Beer
The second part of the brewing process starts when the wort has cooled and the yeast is pitched. This is where things like yeast cell pitching rates, the type of yeast and propagation methods contribute their flavors to the beer. Sanitization and temperature control play key roles during fermentation too by coaxing the yeast into producing beer flavors in ways that only yeast can. Brewing with the right water profile significantly improves the flavor of grain, hop and other ingredients but it also provides the perfect environment for yeast to produce a healthy fermentation. Its time to demonstrate how the pH and alkalinity of brewing water actually improves the taste of beer, but before that we should do a quick review of the third and last part of the brewing process.

Simple Ingredients To Adjust Alkalinity And pH
Packaging is obviously the last part of the brewing process because this is how our beer is stored and delivered to be enjoyed by other craft beer lovers everywhere. After a seven day stay in the refrigerator the beer in the fermentor clears up considerably. During that time the yeast has fallen out of suspension and stuck to the bottom of the fermentor and the cold beer is ready to be kegged or bottled. The carbonation level of the beer contributes to it's flavor as the Co2 levels are adjusted up or down. Higher levels of carbonation tend to give the beer more bite and add to it's perceived bitterness than lower levels of carbonation. Extra care taken during packaging will guarantee that your beer will still taste fresh and full of flavor for many months to come.

There we have it a brief overview of the three main parts of the beer brewing process, with the fist part being identified as the most important for water properties. Once the water properties have been adjusted correctly for mashing and sparging our grains they will be perfect throughout the rest of the brewing process everytime we brew.

Benefits Of Brewing With The Right Water Profile

Whenever I mention brewing water chemistry to most people their eyes start to glaze over and they politely change the subject to something more interesting. Unless of course they're professional brewers, have a passion for chemistry or are career hydrologists with plenty of lab experience. Learning to identify and understand the effects of atoms, ions and molecules on brewing water is a bit more difficult than learning about other areas of the brewing process. The average beer drinker will taste the difference good brewing water adds to the flavor of a beer but they typically won't ask anything about the brewing water profile. They may love the fresh bright hop aroma in your IPA but you'll never hear them say things like 'it could've used a bit more gypsum'. Discussing water properties over a cold one isn't the most interesting topic of conversation for everyone but that could also be the reason why home brewers consider it to be a subject left only to advanced brewers. Creating a good water profile really isn't that hard to do once you've learned a few basics.

Kettle View Of Bright Clear Wort Color And Compact Cold Break
To understand how something as simple as water can make such a huge difference in our finished beer we'll have to talk a little bit about alkalinity and pH. The alkalinity of our brewing water reacts with the potassium released during the mash. To get the best wort color, clarity and conversion rates the pH of the mash should remain stable, somewhere between 5.20 and 5.40 at mash temperature, throughout the mash. But all water contains buffers that resist changes to alkalinity and pH, just how hard the buffers resist change depends on the strength of the buffers. There are several software packages out there that calculate the salt, mineral and acid amounts needed to adjust the water pH to match any given style of beer and they're easy to use. 

A Crystal Clear 4 SRM Color OG Sample
Once you see how easy measuring, evaluating and modifying your own water profile is you'll wonder why you waited until now to try it. By adding small amounts of gypsum, Epsom salt, calcium chloride and lactic acid to your brewing water the mash will produce clearer wort with improved color and flavor and higher conversion rates. The ingredients are readily available at your local home brew store, are inexpensive to buy and completely safe to use in recommended amounts. Mashing within the recommended pH range efficiently converts starch into sugars and the grain bed develops finer particles that dramatically increase it's filtering capacity which makes the wort extremely clear and colorful.

Grain Bed With Fine Particles That Filter The Wort
Overall the most obvious benefit of brewing a recipe using the right water profile is a better tasting beer. For comparison I brewed the same recipe I have been brewing for years using filtered tap water but this time I brewed the recipe using a water profile I modified myself. I can't even begin to tell you how much better the modified water version came out than any of my original tap water versions. The color of the beer was extremely light and it looked great in the glass. The hop aroma was bright and clean and the beer had a nice flavor from the combination of grains and hops.

The most remarkable thing for me is that I had also managed to capture that nice bready taste noticeable when exhaling through my nose after swallowing a sip of beer! Up until now I had found this one single component lacking in almost all of my previous beers. Some of my beers would have this bready finish but I'd never been able to consistently reproduce it with every brew until now. It never occurred to me that this bready finish was attributed to the brewing water and mash pH more than it was to the grain bill or yeast alone.

It's important for a brewer to produce the best tasting example of their beer consistently and that basically means having the ability to mash grains within a recommended temperature and pH range throughout the year. Ultimately that comes down to being able to brew using water that has consistent properties throughout the year. Water properties from the same location can vary widely from season to season so each batch of brewing water needs to be analyzed for it's mineral content and pH value before being used to brew beer  and then modified as needed to match the beer recipe's water profile. 

Using The Tools Of The Trade

There are two different approaches to modifying brewing water. The simplest approach is to start off with either distilled water or reverse osmosis water that basically has had all mineral content removed from it already. This provides a source of water with a consistent baseline to use when calculating the salt, mineral and acid additions needed to build a particular water profile. I prefer this approach over the alternative of doing frequent water analysis to determine the seasonal adjustments needed to compensate for changes in the water's properties. In my view it's definitely easier to start off with water having the same properties because water profile adjustments can be easily repeated based on the results of prior brews.

This becomes even more important when entering values into the EZ Water Calculator because when using reverse osmosis or distilled water you simply have to enter the volume of water in gallons as 100% of the total water volume. Otherwise you have to take the results from your latest water test then enter those amounts as parts per million of calcium, magnesium, sodium, chloride and sulfates in order to calculate the amount of additions needed to reach the recommended mash pH value.

Calculating 4 Gallons Of Mash And 5 Gallons Of  Sparge Using Distilled Water
Once the confusing part, whether to use your local water supply with seasonal water quality reports or reverse osmosis or distilled water with their consistent properties, has been decided and entered we need to enter the grain bill. Darker malts have an acidic value which works to lower the water's pH value, which is really just an indicator of the water's alkalinity. In contrast pale malts do very little to lower the water's pH because they are not as acidic as darker malts. We can't rely on pale malts to lower the water's pH enough but by adding lactic acid and other minerals we can reduce the water's pH while strengthening the water's buffering properties.

Darker Grains Add Acid And Lower The pH More Than Lighter Grains

Buffering properties?! Let me explain. Let's assume that reverse osmosis water has had all of it's minerals and salts removed, in effect weakening it's buffering capabilities. Now the slightest additions of either acid or base minerals will swing the pH values down or up accordingly. But as we add gypsum, calcium chloride and Epsom salt to the water we start to strengthen those buffers to the point where they become much more resistant to pH value changes when acid or base minerals are added. This is exactly what we want in order to maintain a constant mash pH in the 5.20 to 5.40 range throughout the mash. If you've decided to use your local water supply you have to determine it's pH, salt and mineral content to understand it's buffering strength and then calculate the additions needed to maintain the recommended pH range during the mash. 

Digital pH Meter With 4.01, 7.01 Calibration Buffers
You've managed to hang in there up until now. I can tell because you're still reading this post. We can assume you are serious about your brewing water properties and learning how modifying them correctly will produce the best tasting beer ever. Going forward you will need a quality digital pH meter with a resolution of a tenth of point and calibration buffer solutions to correctly calibrate the meter before each pH reading. A digital scale is also needed that can measure to the tenth of a gram. This type of scale is very useful when measuring out salt and mineral additions. Each salt or mineral has a different weight per teaspoonful so having the ability to accurately measure grams will make modifying water properties much easier. Lactic acid comes in liquid form and the additions are calculated in milliliters so a small syringe like those used to administer children's doses of liquid medicine are perfect to use.

What's Next?

In part II of this series we will build on the basics laid out in this post and brew a hypothetical batch of beer using a water profile made from scratch. I've already brewed several batches of beer using the same recipe and brewing water profile and I will include every step of the brewday in detail. If you choose to you can brew a batch of beer for yourself at your own pace by simply following the brewing instructions. The basic recipe is an East Coast IPA style made from a pound of CaraPils and eleven pounds of US 2 Row malt. Two ounces of Centennial hops and four ounces of Cascade hops provide the bittering, flavor and aroma. But the recipe really comes to life when mashed using the modified water profile we will build together and the resulting beer will be delicious.

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