Brewing Water Series: What is the Best Water?

Water chem

Photo by Sarae @ Flickr, under Creative Commons


I saw this title pop up on a forum post recently. It’s an incredibly loaded question, and certainly something that opens up a good deal of debate. We are also going to have to accept a lot of subjectivity (my opinions) in this discussion.

The best water is that which will help put the very best beer in the glass, and there are many ways to get there. I feel like I have written this post many times, but all of the issues below need to be addressed, so maybe we should look at water from a different perspective.

1. Consistency. Knowing where to start with your water is very important if you are doing any mineral additions. So a brewer’s water profile from a lab maybe necessary. But before you do that, answer this question:

Is my tap water consistent? This should address sources of the water supply and any seasonal issues, such as agricultural or road run off. Sanitation chemistry is also important. This information can be gleaned from a call to your municipal supply, their website or through periodic testing if you have a well.

Reverse Osmosis (RO) and De-Ionized/Distilled (DI) water provides a very consistent source, but will often require mineral additions for the all-grain brewer. However, you should test the source regularly for consistency. Bulk commercial water systems at grocery stores sometimes have inconsistent maintenance and home filter systems will require regular replacement of filters. The brewer must consider the costs and convenience. A TDS meter is an inexpensive solution and provides an indication of residual minerals and filter effectiveness. Bottled bulk water remains an excellent choice for brewing. Just remember that spring water contains some minerals that you may wish to account for in any mineralization for brewing.

Most whole home water softener systems will produce sodium or potassium rich water that is unsuitable for brewing. It is a great solution to feed a small RO system with a predictable hardness level.

2. Active Charcoal Filtration and Treatment. All municipal water carries some sanitation chemistry to ensure safety. While this chemistry may vary in strength, it is relatively easy to deal with. Chlorine and Chloramines will react with mash phosphates to form polyphenols, which express as bandaid, plastic or strong smoky flavors in beer.

Allowing the water to stand overnight, or pre-boiling should gas off chlorine products, but chloramines are much more stable than chlorine. Boiling brings other benefits, such as potentially lowering the water alkalinity, precipitating bicarbonates. This requires some planning ahead and uses fuel.

Slow filtration with active charcoal filters (you can find these at any home improvement store) will remove much of the chlorine and chloramine, as well as removing other chemistry that may affect flavor. The contact time with active charcoal is critical and we should be concerned with any residual chlorine/chloramine products after filtration, so a slow flow is required.

The most complete treatment is the use of Campden tablets or Metabisulfate (Sodium or Potassium). These products react nearly instantly with chlorine and chloramines to produce sulfur which gasses off quickly. The amounts required are very small, 1/4 tablet of Campden crushed will treat 5 gallons of water. These same chemicals are used as sanitizers and stabilizers in wine and mead making – but at much higher levels.

3. Brewing Method. If you are an extract brewer, the extract already contains the necessary minerals. It is best then to use RO or DI water to avoid over mineralizing the beer. Minor adjustments can certainly be made, such as small amounts of gypsum for hoppy beers or calcium chloride for malt forward beers.

All grain brewers have different requirements. Mashing will require hitting a mash pH range (5.2 – 5.6) and water alkalinity has a very dramatic impact here. The use of RO/DI water will usually require some moderate adjustment of minerals. Without, the beer may seem flabby and lackluster. Judicious use of liquid acids or alkalis may be required.

Your source water’s alkalinity (usual as CaCO3) is the critical value. You can get this through lab testing, or you can also use an aquarium testing kit. This value will allow you to estimate the necessary acid/alkali required to strike a specific mash pH.

4. Complexity and Convenience. Even for all grain brewers, one can make this very complicated or very simple. The most important part, as mentioned is hitting the right mash pH. This will allow for full extraction of flavors and sugars. The rest is really a focus on nuancing a beer’s desired mouthfeel and sharpness or roundness of malt and hop flavors.

Creating your own water at home or buying from the store all can have inconvenient elements. Decide what works for you, your time and budget. Figure out which will give you the best results.

Regardless of your brewing style, managing your brewing water is an important part of brewing. Water chemistry affects mash pH, boil pH and the formation of break material in the kettle. The residual -ion concentrations affect mouthfeel and enhances flavors.

Where to start? There are many guides on the internet that provide different approaches to this topic, including here at Accidentalis. Some are very complicated. Depending on your comfort with chemistry, you can go extremely technical. Water chemistry is pretty fascinating.

I will warn that there is not a one-size-fits-all solution. Anyone selling you something that ‘fixes’ mash pH is ignoring the facts that not all water sources or grain bills are the same. Chuck that 5.2 pH buffer that your LHBS sold you into the trash and not in your mash.

Buy some gypsum and calcium chloride, as well as some lactic or phosphoric acid. Get some fresh baking soda and you have all of the minerals you need for basic water management. Save up to buy a decent pH meter, something with replaceable probes and learn to use it properly.

Start conservatively – you don’t want minerally beer. Or maybe you do. You can treat finished beers with mineral solutions to figure out the levels you may like.

Do some research online. Visit the Homebrewtalk Brewing Water Primer for a simple place to start. Get your water tested and learn to use tools like the Bru’n Water Spreadsheet or Brewer’s Friend Water Calculator. Use your new pH meter to confirm the estimates from those water calculators. Keep at it – brew and take good notes. Rebrew the same recipe with a different water profile. Note the differences. Find a mentor and brew together and enjoy the ride!



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6 Homebrewing (Non)Controversies

After reading through Drew Beechum and Denny Conn’s Experimental Homebrewing book, I thought through some of the questions that I see repeatedly asked. Drew and Denny touch on some of them. The spirit of their book resonates with me… find the answers on your own through experimentation.

The reality is that for many of these questions – the answers are not black and white, and should be informed by experience and preference. Some issues are preventative in nature (if you don’t do this then it’s ruined), which makes seeing the real nature of an issue a bit fuzzy. The spirit of experimentation, and thankfully, a thoughtful approach to the question is also the core of Marshall’s work at

I have asked Chris Colby from the Beer and Wine Journal to add in his two cents, based on his years of experience and knowledge. He was kind enough to weigh in. Beer and Wine Journal features articles on Brewing and Food from Chris and James Spencer.

Below are a few of my favorite (non)controversial topics:

Should I rehydrate dry yeast before pitching?

I am a huge proponent of rehydrating dry yeast to the manufacturers specifications, which do vary slightly. I rehydrate to ensure that my yeast is proofed, healthy and ready to go. I also make sure to pitch the right amount of yeast and dry weight measurement is extremely convenient and simple. Plus there is no need to mess with a starter. Of course, there are kits and even some dry yeast manufacturers that do NOT recommend rehydration. FYI, The American Homebrewers Association recommends rehydration.

Will your beer be ruined if you do not rehydrate? Of course not. Many people don’t want that extra step in their brewday. There is data that suggests that a portion of the dry yeast cells are lost when rehydrating in wort, largely due to osmotic pressures that destroy the cell walls. But there is also an argument that those dead yeast cells convert to nutrients for the remaining healthy cells. Brulosopher did a cool experiment on this topic.

Why is this controversial? It shouldn’t be. The home brewer needs to determine what works well for their particular mindset and equipment!

Chris Colby: Rehydration is a good thing — if it is done correctly (and the yeast tempered before it is pitched). If you’re not going to bother to slowly cool the yeast before pitching (stir in some wort to do this), it’s better to just pitch the dried yeast. Correctly rehydrating yields a high cell count of viable, active yeast. Skipping rehydration leaves a smaller — though almost always adequate — population of yeast to ferment the beer.

Should I make a starter?

Another recurring question that just makes my eyes roll. If you are asking the question, then you have seen recommendations to build up your yeast cell count appropriately to match both your fermentation volume and the gravity of your wort. There are cases to be made on either side of the equation, and this is really an issue for liquid yeasts, not dry. For example, White Labs recommends both of the following:

  1. “At White Labs we package our yeast with a concentrated cell count which does not require any additional propagation time. Therefore, our vials can be directly pitched into a five-gallon batch of wort, giving you approximately a 5-15 hour lag time.” (White Labs FAQ – What is meant by pitchable quanities?)
  2. “A yeast starter is used to initiate cell activity or increase the cell count before using it to make your beer. The yeast will grow in this smaller volume, usually for 1-2 days, which then can be added to 5 gallons of wort.” (White Labs Homebrew Starter Tips)

And that maybe confusing. There are two real factors to consider:

  1. Pitching rate recommendations vary, but generally the home brewer is encouraged to pitch at least 0.75 – 1.0 million cells /ml / degree Plato for an ale, double that for a lager. So gravity has a dramatic impact. Many professional brewers pitch 20-30% more yeast at 1 – 1.5 million cells / ml / degree Plato.
  2. Viability is important, especially with liquid yeast as cells begin to die quickly when not in an optimal environment. The starter proofs the yeast (waking up the viable cells and starts their growth) and allows the replication of cells to adequate levels. Check the dates on any yeast product you purchase, and make sure the LHBS stores it properly in a cooler.

Finally, the reality here is that this is largely a horse shoes and hand grenades game. Adding a single vial of fresh yeast to 5 gallons of moderate gravity beer (under 1.070) will make beer, and often very good beer. However, when I am planning to brew, yeast viability and pitching rates are another control to ensure my batch has the best possible chance of successfully completing fermentation without any yeast derived off flavors. I have seen little difference in my fermentations when generally estimating the amount of yeast I am pitching, versus doing cell counts and carefully pitching the right rates. Yet I still believe this is the best practice to produce repeatable beer character and quality. 

Chris Colby: I’m a big fan of making an adequately-sized yeast starter. If you want to be sure you have a population of active, healthy yeast, sufficient to yield an ordered fermentation, making the effort to make a yeast starter will be worth it. You can skip making a starter for low-gravity beers if you are positive your yeast is healthy, but I like to see proof that the yeast is healthy when I brew. So, I always make a starter.

Liquid Yeast versus Dry Yeast

I really do not want to spend a lot of time here. There are pros and cons to each, but we live in a time with an incredible universe of options in yeast selection, in liquid or dry form.

  1. Liquid Yeasts offer an amazing variety of strains, all healthy and ready to make wonderful beer. They bring classic characteristics to specific beer styles. However, handling requires them to be kept cool and shipping liquid yeast during summer months or warm spells can make that difficult. Liquid yeast can also be pricy. If you choose not to do a starter, and wish to pitch at rate into 5 gallons of a 1.070 beer, expect to buy at least 3 vials at about $7.00 each. That pushes the costs per batch up – and another great argument for making a starter and building up to the right pitching rate.
  2. Dry Yeasts are starting to expand in variety, but quite limited relative to liquid yeast choices. Many are ‘controversial’ based on their described characteristics and proposed usage. Here, you should research your yeast choices appropriately. I love dry yeast for convenience and price, especially in very clean ales with US-05.

Experimentation is key. Brew a batch and split it with different yeasts to see the differences. Generally the vectors are in lag times, attenuation, flocculation and clarity, and perhaps more importantly in yeast derived phenolic and ester character. Many brewers like to pitch at the bottom of the recommended temperature range, and control the rise into their desired control point.

Chris Colby: Dried yeast has come a long way since the early days of homebrewing. I brew with both liquid and dried yeast depending on the circumstance. And, I always keep a sachet of dried, neutral ale yeast (US-05) in my fridge as a backup.

Should I secondary or just primary ferment my beer?

There has been a long tradition of racking beer off the yeast as primary fermentation nears completion to avoid yeast autolysis. You will find that recommendation from most starter kits (which ship with a secondary carboy and racking equipment), older books on brewing and many ‘old school’ brewers. The second argument is about conditioning and clarifying the beer. Marshal at has done an EXBeeriment on this topic, along with a great photo of one of his brewing helpers!

The term “Secondary” has lost its way a bit in the homebrewing world. In professional brewing, it traditionally referred to a secondary fermentation step that may have been necessary when malts were less modified and a high level of proteins remains in the wort or a product requires additional processing such as in high gravity brewing. Often, secondary fermentations are krausened with fresh yeast to ensure complete attenuation and additions of fruits or other spices added to ensure their character did not scrub out with the release of CO2 during primary.

We should also recognize that autolysis is largely a bulk fermentation issue with tall conical fermenters at commercial breweries. There is a tremendous amount of pressure with the weight of many barrels of beer bearing down on the yeast at the bottom of the cone. This can cause a very rapid die off of cells that break down and can create off flavors. MOST homebrewers do NOT have this fermentation geometry or problem. I primary in ½ barrel conical fermenters and have left yeast in the cone for 6 weeks without autolysis. I have also left primary fermentations in buckets for as long as 4 months without racking with no off flavors. Autolysis is simply not a big issue if you are fermenting with healthy yeast and appropriate techniques.

I do secondary when I am aging beer on wood or fruit. I seem to have better results when the beer is nearly fully attenuated and then add more sugars for fermentation (fruit). I also rack as gently and slowly as possible, often under the cover of CO2 to reduce chances of oxidation. Oxidized beer tastes pretty bad.

Secondary may also be used for conditioning in bulk. Many homebrewers rush their beers through fermentation and into the bottle or keg, and this certainly is possible and viable. I find that a conditioning period, typically whatever is convenient in my primaries, results in a cleaner and clearer beer. I like to do this at lagering temperatures, but have also done long conditions at room temperature, and under pressure for many months.

The premise of conditioning is that the residual yeast in suspension clean up by-products of fermentation that may result in off flavors. The other benefit is the clearing process where tannin and polyphenols slowly fall out of suspension (particularly in lagering where chill haze is cleared). I have worked out my pipeline such that virtually every beer gets an extended 3-4 week conditioning period. If I am doing a hoppy beer, part of that conditioning time will involve dry hopping for a few days or weeks towards the end of the period. If doing any extended conditioning, stay on top of your cleaning and sanitation regiment.

So the real answer is that you should do what you are most comfortable with, fits your personality and schedule, equipment and produces good beer. The biggest benefit of a secondary for most homebrewers is to free up that limited primary fermentation space for the next brew!

Chris Colby: With most reasonably flocculant yeast strains, racking to a secondary fermenter is not needed. For a few powdery yeast strains, racking can result in the beer dropping clear sooner. Given that racking will always introduce oxygen to your brew, I avoid racking to secondary unless it is necessary.

Batch Sparge versus Fly Sparge versus No Sparge

Advances in quality of malts, availability of inexpensive gear and the seeming attraction of engineers to homebrewing have really moved homebrewing forward, resulting in the ability to produce exceptional beers at home. Lauter Tun design is no exception, and we really have Denny Conn to thank for developing and showing the benefits of batch sparging as well as his many other contributions. Still it seems that sparging technique is a polarizing issue with homebrewers.

Lautering or Sparging is the process of removing the residual sugars from the mash after the mash process is complete. By measuring the gravity and volume of the first runnings, we can show that highly concentrated wort is produced in a short volume of wort. Additional water is added that rinses or extracts the residual sugars, and dilutes the first runnings to our target gravity, while providing enough liquid volume to achieve our batch size to boil. While extract efficiency is often used to measure the difference between traditional fly sparging and batch sparging, there is no definitive advantage to either other than necessary time to complete.

Batch sparging is the addition of all or part of the sparging liquor to the mash after the first sweet wort is completely run off. The technique really is straightforward and some simple math can produce excellent results (gravity targets and volume related). You add your sparge water and stir very well, turning over the entire mash bed a few times. Then simply run off the resulting wort after a quick vorlauf to reset the bed filter and clear the wort. If you calculate appropriately, you leave behind only that wort not accessible by your drain. Mash tun design here is important – and Denny Conn’s website shows his ideal batch sparge vessel. You can also batch sparge in round coolers and kettles – and I have done this many times with my system. The result is a process that takes only a few minutes with great results

Fly Sparging is the slow trickle of sweet wort run off while introducing a slow flow of sparge liquor to the top of the mash bed. Two things play here: the mash bed remains undisturbed while gravity and osmotic pressure allows the sugars to be extracted. Fly sparging is the traditional professional lautering technique and homebrew systems attempt to replicate this with fairly sophisticated pumps and delivery systems as well as mash tun designs. Lautering stops when the boil volume and gravity is achieved. This method takes patience, and is subject to slightly different mash chemistry as the buffering capacity of the mash is exhausted and the rise in mash pH can encourage tannin/polyphenol extraction towards the tail of the process. This is the method I prefer in my brewery because my system has the capability built in, and I usually see a few points of additional efficiency. It also slows me down a bit in the brewery, which can be hectic.

No Sparge brewing is essentially mashing with the full boil volume of liquor factoring in the grain adsorption. This results in a thinner mash, and may require higher amounts of grain. Extract efficiency is often lower than in other techniques. No sparge may also require extended mash times as the thin mash MAY dilute enzymes relative to the starch concentrations. A single run off is then required to achieve your boil volume. I should point out that mash chemistry becomes more important when dealing with your water’s alkalinity and the diluted buffering capacity of the grains.

So which technique is best? If it works for you, and meets your personal criteria, you are right. A good brewer will adjust his techniques to deal with any potential challenges. Who would have thought that three techniques (each with myriad hybrid variations) can achieve a great product?

Chris Colby: I’m a big fan of fly sparging, although my (initially low) opinion of batch sparging has risen over the years for a variety of reasons. (I’m one of those crazy people who changes his mind in the face of convincing evidence.) I’d urge beginning all-grain brewers to try both methods a few times, then decide for themselves. I’d also urge beginners trying fly sparging to not worry about exactly matching the inflow rate of sparge water with the outflow rate of wort. Try “pulse sparging.” Add a volume of sparge water, then run some of it off (until the water is just above the grain bed), then add another volume, run it off, and keep repeating.

Traditional Mash Tun versus Brew In A Bag (BIAB)

This is hands-down my favorite polarizer. BIAB initially grew out of the Australian homebrewing community, and is a testament to efficient and innovative use of vessels. It is now very popular worldwide AND people get seriously obsessed and often defensive about this technique, not unlike their support of sports teams. Traditional method brewers seems to be offended that BIAB ignores some of the guidance for brewers over the past decades: very thin mashes, possible tannin extraction, using looking a little silly lifting a giant bag of hot dripping grains out of a pot.

BIAB normally uses a single vessel, lined with a fine mesh bag, to mash the full volume of grain and liquor. You then lift the bag and let it drain into the boil kettle, and may or may not squeeze the bag (another controversy) or dunk sparge into some top up water. Everything else is the same – maintaining mash temperatures and mashing times (although perhaps slightly extended).

This is probably the most convenient and simplest method of all grain brewing, particularly for small batches, but even a commercial microbrew system sports a modified version of BIAB using built-in hoists and stainless mesh baskets nested inside the big boil kettle. I use this method for many stovetop test batches to good effect.

From a cost perspective, BIAB is an attractive alternative to complicated and expensive 3 tier or 2 tier systems, and what I recommend initially to folks that want to start all grain on a budget. A 5 gallon setup only requires a 8 gallon pot (for a full volume boil) or a cooler for a mash tun, a strong fine mesh bag to hold the grains (there are now commercially available bags for this!), and a burner capable of boiling 6-7 gallons of wort. The only real downside is danger from handling the hot bag, which can also get prohibitively difficult to lift with 20-30 pounds of wet grains. Many folks rig some kind of hoist from their ceiling or a ladder to make this easier. Compared to an expensive RIMS system, BIAB is very attractive!

Anyone who disparages BIAB brewers (or extract brewers for that matter) has not judged many flights in competition. Great beer really comes from good brewers with attention to detail. Each technique brings potential issues to the table, and good brewers recognize and respond to those issues to put great beer beer into the glass.

Chris Colby: I’m a crotchety old man (in outlook, if not actual age). You BIABers get off my lawn!


Controversies are generally created out of lack of empirical information and the stubbornness of humans unwilling to look at the other side of an argument. We naturally chase metrics that allegedly prove our skills are superior, such as extract efficiency. So much of brewing remains untested to the scientific method, particularly at the scale of the home brewer. Proof, in my mind, remains in the glass and on the palate.

Finally, we must understand that the prevailing common knowledge of brewing changes. The world of brewing has moved forward. Malts are so modified today they have become nearly bulletproof in terms of yield. A global array of fresh yeast is at our fingertips and hop varieties have exploded. (un)Fortunately, a dizzy amount of information is available on the internet. As the old saying goes, “I read it on the internet so it must be true. NOT.” We ignore this skeptical frame of thought to our detriment. Often, we cannot find a definitive answer to our questions – so we MUST test and experiment. Not every homebrewing hero is right all of the time, so questioning the status quo and asking questions of experienced homebrewers can lead you to the right answer.



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Measuring Mash pH in Practice

Mash pH Workspace
I see a lot of questions asked about WHEN one should measure mash pH. I thought it would be useful to walk through the steps first and discuss the acid and buffering system of a mash in the real world, as well as some thoughts on a good meter.

Using a quality pH meter is important, as is the calibration, storage and maintenance of the device. Fortunately, we don’t need a lab quality meter and the prices of good meters are reasonable. Here are a few recommendations taken from and Braukaiser’s website:

  1. Choose a meter with resolution and accuracy out to +/- 0.01/0.02 pH units. This may limit your choices to meters over $100. A 0.1 resolution meter maybe enough for mash pH measurement and give more choices under $100. You get what you pay for however.
  2. Choose a meter that allows for a 2-point calibration. You will need to calibrate ‘slope’ between 4.01 and 7.01 pH solutions, appropriate pH ranges for brewing.
  3. Decide if you need Automatic Temperature Correction (ATC). This will add some cost to the meter, but also drop the need for highly accurate temperature measurements along with pH. Temperature and wort pH correlate – ATC helps to compensate
  4. Choose a meter with replaceable probes. Many bench and pen-style meters allow for probe replacements, and often the probe is the source of problems, and the most delicate part of the instrument.
  5. Replace your calibration and storage solutions often. They degrade over time and can become contaminated with use.

Many people recommend the Hach Hanna Pocket Pro+ and either the Milwaukee MW101 or MW102. I have the MW102 and have been very happy with its performance. Hanna meters are bought directly from the Hach website, and have a good reputation for support. You can find Milwaukee meters on Amazon – and watch for a sale. Like any good measurement instrument, you get what you pay for. A $30 meter will most likely not give accurate results or last.

I recommend immediately calibrating your meter per the manufacturer’s recommendations. This varies meter to meter – so read the instructions correctly. The Milwaukee meter allows for 2-point calibration, but across three possible values, 4.01, 7.01 and 10… so setting the slope should only use the 4.01 and 7.01 solutions, and you skip past the 10 calibration point. Most meters ship with pillow packets of buffers that can be used when mixed with distilled water. The pillows also store very well, and are a good alternative to buying premade solutions.

It is also recommended to perform a stability test. This measures the probe’s ability to stay constant in a known pH solution (like the 4.01 buffer or the 7.01 buffer) over time. Ideally you should see little shift in variation and be able to chart the errors. The meters we use are not lab-grade, so there will be swings in the errors. A great article posted by AJ DeLange at details this process.

All meters should be stored correctly and storage solution changed regularly. This ensures the probes do not dry out. Store the meter inside your house in a stable environment. Don’t subject it to large swings in temperature.

Using a meter during brewing

There seems to be some confusion about when to take measurements, and what those measurements actually mean, and steps required to fix a problem, should one arise. My process is fairly straightforward. A 60 minute mash is easy to break into 15 minute or 10 minute segments, starting at the 15 minute mark.

Setup an area that is convenient and gives you some room to work. You will need the following:

  1. Paper towels or a cloth
  2. A metal or glass dish that can cool quickly. I use a nest of old metal ceramic coated mixing bowls to create an ice bath. This keeps the bowl chilled and a small one or two ounce sample of hot wort cools very quickly.
  3. A sampling vessel. I use shot glasses.
  4. A mesh filter – this is used to remove stray bits of grist.
  5. pH Calibration solutions and a cup of distilled or RO water for rinsing.
  6. Something to take notes on… I use the back of my Adjustment Summary sheet printout from Bru’n Water.

I typically take measurements at 15 minutes, 30 minutes and toward the end of lautering (output of wort from the MLT to the BK). I note both the temperature of the wort (MW102 has ATC with a temperature probe) as well as the pH. If the measurement is not where I expect it to be, I will decide if I need to make an adjustment, but generally I will let things ride, and confirm the measurement 5 minutes later. At that point – I will know if I need to stop my mashing cycle and add either acid or alkali.

I never add more than needed to move the pH 0.1 units in either direction. And only when I am well outside the 5.2 – 5.6 mash pH range. Stir extremely well and restart the mash at that point, and I extend my mash period by 15 minutes.

Procedure – mash and sparge:

  1. Calibrate your meter if you haven’t already. Rinse the probe in DI water.
  2. Remove a small 1-2 ounce amount of hot wort and place it into the cold metal bowl, swirling to cool. When the wort is cool to the touch, it is ready. NEVER put your probe into hot wort – this can seriously damage the probe. Always make measurements with the wort at or near room temperature.
  3. Pour the cooled sample into a shot glass, filtering through the mesh if needed to remove as much of the grist as possible. Grains sticking to the probe can alter the reading.
  4. Place the pH probe and thermometer into the sample and wait for the readings to stabilize. This may take a few seconds. Most probes have an indicator for when the sample reading is good.
  5. Write down the readings and rinse the probe. Place the probe back into storage solution until the next reading is required.

It is a good idea to decide where in your system you will take the measurement, for consistency. I like to sample from the return hose on my RIMS system. Do what is convenient, but apply it consistently through your procedures.


I have written before about mash pH being a dynamic system. For most brewers, we are looking to get into a specific range of pH, and tolerate a +/- reading of about 0.02 with a good meter. In reality, the pH of the mash drifts as the buffering capacity of the malts and carbonates are exhausted. This may cause pH to shift up. In some mashes, the pH will drift down. You are looking for the 30 – 45 minute measurements to stabilize at or near your target mash pH. In reality, if you target a mash pH of 5.4, which is the safe middle ground for most beers, you will find readings above and below that mark. A perfect reading of 5.4 at 15 minutes may show that your mash is going to drift away from that mark later. Experience and patience is required. DO NOT PANIC if your readings are not on target! Reacting too soon and adding acid or alkali to control the pH may lead to adding too much and having a more dramatic and potentially harmful impact on the mash.

I like to pre-calculate both an acid and an alkali addition in Bru’n Water so I know that I am adding only enough to theoretically impact the mash 0.1 units in either direction. This prevents me from adding more than necessary, and forces me through planning to be aware of where I should be. Combined with experience, I can make the right decisions. I have seen way too many instances where people respond and attempt to add a bit, measure, add a bit more – and the result is a disaster. Don’t waste your time chasing a pH target without a plan.

The Effects of Mash pH

We manage mash pH to make sure optimal enzymatic activity in the malts. Bringing your mash into the proper zone ensures the full conversion and extraction of sugars as well as give the fullest flavor from your malts. Mash temperatures, of course, also impact fermentability and can favor certain characteristics.

I have a goal of getting to conversion as quickly and consistently as possible, which means that my water and mash chemistry must be accurate from the outset. As soon as I mash-in, the grist is hydrating and enzymes are activated and acting on the available starches. As the grain continues to hydrate, more starch is released, as are buffers. At the beginning of the mash, this chemistry is dynamic and chaotic, but will seek a balance. I want this process to stabilize as quickly as possible without intervention through the entire mash, without passing outside of the 5.2 – 5.6 pH window. Your recipe will have a dramatic impact on the change over time in the mash. A recipe heavy in roast and crystal malts will start low and drift up, where a pale ale recipe may start in high and drift down. Experience will show you what to expect.

Checking for conversion

I have stopped using the iodine test for conversion as I can usually smell and taste and see the results. That said, the pH sample is a perfect opportunity to test with iodine. (Google for iodine conversion test) I have also occasionally used a refractometer to measure the increase in gravity to double-check. Many brewers are seeking to shorten their mash times and seeing full conversion in just 10-20 minutes. I find that on my system conversion is complete around the 45 minute mark, however, I continue to mash for the full 60 minutes and deploy a mash out. I find that this aids in lautering and helps with my efficiency, but your mileage may vary.

pH during lautering/sparge

When you sparge, the mash has exhausted most or all its buffering capacity, which makes the sparging liquor’s alkalinity an issue. A high pH over 6.0 can extract unwanted tannin from the malt, which typically show as astringent. If you are lautering with RO or DI water, then you can lauter out without concern. A bit of acid can also bring that liquor pH under 6 to make sure that the run off stays under 6.0. When using water with alkalinity – the pH will rise more rapidly as it is introduced to the mash – and you should treat that liquor appropriately with acid. If you do NOT sparge with RO or DI water – you should regularly check your run off pH to ensure it is below 6.0. Otherwise, stopping lautering when the gravity reaches between 1.012 or 1.010 will also help reduce tannin extraction into the kettle. If you are experiencing astringency in your beers – this is a likely place to start.

Mash pH will follow into the kettle, where it is further reduced both by boiling and by dilution of the sparge water. Some brewers also manage this pH, and will add some or all of their minerals into the kettle. This will cause a fairly dramatic reaction as the buffering ability of the wort is diminished. Many books recommend bringing the boil pH to around 5.2 to ensure large fluffy break formation. Chris Colby of covers this an article. I have gotten into the habit of adding a very small amount of acid and watching for the large fluffy break formation, rather than relying on mineral additions.

pH of Finished Beers

The yeast will create the proper pH environment for their replication and fermentation phases. There is evidence that boil pH has an effect on the finished beer, and can certainly impact yeast stress. In most cases, you do NOT need to worry about it before fermentation. There are many exceptions – especially sour mash or sour wort derived beers, but even then some specific yeasts and souring bacteria thrive in the low pH environment.

Most beers will finish in the low 4.0-4.4 ph range. You should be willing to explore adding lactic or phosphoric acids to beers to meet specific characteristics. I like my saisons to have a tart finish, and find that a tiny addition of lactic acid (always to taste) to help sharpen up ester expression and cut down on phenols. Other beers, such as stouts may benefit from adding baking soda to sweeten up and emphasize malt characteristics. Many people believe this cuts down some of the sharper roast characteristics that may be undesirable.

Using a pH meter at this point can be very helpful in note taking and ensuring that batch to batch your beers are consistent.





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