Thursday, 30 November 2023

KegLand - pH Meter (KL04169) - Hands on Review

Introduction

We're big proponents for water chemistry adjustment in brewing. Water is, after all, the biggest single ingredient used when making beer, and there's no doubting the science and research behind the role it plays when making high quality beer.

We've written several articles around water chemistry in brewing on this site, and even made it on Spike Brewing's website with our very own feature article on this very topic - but understanding what adjustments you need to make is only the first piece of the puzzle. The second part is having the equipment you need to accurately and reliably measure your water to ensure you're making the correct adjustments, and putting the correct starting numbers into your brewing software.

pH is one of the key metrics when making water adjustments - and as you'd expect, you need a pH meter in order to test the pH of your source water and brewing water throughout the brew day, to make sure things are tracking as you expect.

We've been using our KegLand pH meter (KL04169) for over a year now, and we wanted to share our experience with this piece of equipment for others looking at including a pH meter in their brewing equipment arsenal, or looking to upgrade or replace an existing one.

Packaging & Storage

The KegLand pH meter comes in a nice solid, plastic case. Having a rigid case like this is great to prevent the meter from being damaged when not in use. There's also a clip-in style cradle that holds the meter in place within the case, so it doesn't move around at all when stored.

Instructions are included too (also available online), which is great and gives you some useful information about how to use the pH meter, take care of it, and perform a calibration to ensure it continues to give you accurate results. 

Importantly, the sensitive electrode on the end that is used to take measurements in fluid samples also has a cap, seal, and small piece of sponge in the bottom. It's imperative that the pH meter is stored in a special electrolyte solution to maintain the electrode and prevent it from drying out, so a small amount should be added to this cap to keep it topped up as required (the pH meter ships with some storage solution already in the cap). 

Don't let this intimidate or deter you though - the storage solution is cheap, and you'll only need a tiny bit in the cap for storage, so even a small bottle will last a long time. You will need to purchase this separately, and currently sells for AU$4 on the KegLand website for 25mL.

pH storage solution

One thing we have noticed is that if storing the meter lying down, even with the rubber seal in the end cap, we still had the storage solution leak out and crystalize on the outside of the cap, leading to the sponge and electrode inside drying out. This can deteriorate the life expectancy of the electrode (or ruin it completely), but we were lucky in our case that it's still working fine and giving us accurate results after rehydrating it with more storage solution in the cap. We tend to store it on it's end (with the electrode facing down) which seems to help prevent the storage solution from leaking out of the cap. Another tip to avoid this happening is to not add too much storage solution into the cap - you really only need a very small amount in there.

Lastly, within the case you'll find three calibration buffer solutions which when mixed with water, give a known pH value that you can use to calibrate your pH meter - more on this shortly.

The pH Meter

The pH meter itself is bright orange in colour, made entirely of plastic and has a small monochromatic screen used to display your readings and other information. As you'd expect for something you need to submerse in liquids, the unit itself is water resistant, and along with the screen it features three buttons on the front; CAL for calibration, HOLD to hold the currently displayed value on screen, and ON OFF.  

The pen-style design is good and measures 185mm high x 40mm in diameter. It's lightweight (88g), and the unit can be held and operated with a single hand, including pressing the buttons. The screen is adequate too, with decent brightness and is able to be viewed from varying angles to be able to read what is displayed on the screen.

Automatic Temperature Compensation (ATC) is another neat feature too, meaning your readings don't have to be taken at a specific temperature to be accurate. The recommended temperature range for readings is from 0-50°C - though we'd recommend sticking to the middle part of this range - as sticking the meter in hot water/wort will shorten the life of the sensitive electrode.

Replaceable Electrode

We mentioned above that the electrode on any pH meter is a sensitive component, and it's considered a consumable part. Even the most well looked after pH meter will eventually have it's electrode deteriorate and need to be replaced. For this reason, it's a really good idea to invest in a pH meter where you can replace just the electrode, and not have to purchase an entire replacement pH meter.

Our spare replacement electrode - probably a good idea to always keep one spare on standby - you don't want to be stuck without a working pH meter on brew day!

Telltale signs of the electrode needing replacing are wildly inaccurate or unstable/fluctuating readings - even after performing a calibration.

As you'd expect, the KegLand pH meter does allow for the electrode to be replaced, meaning when the time comes you can simply swap out the electrode. The electrode currently sells for about a third of the cost of the entire pH meter, so it's definitely more cost effective to replace the part only (as you'd expect). We haven't had to replace our electrode (yet) but we do have a spare on standby and ready to go for when the time comes.

Calibration

Calibration is an important part of ensuring your pH meter gives you accurate readings. Some cheaper pH meters only feature single or dual-point calibration, making them less accurate than the triple-point calibration featured on the KegLand pH meter. It therefore comes with three different buffer solution powders that you can use for performing said calibration. It's recommended a calibration be run at least once a month to help maintain accuracy. Accuracy is claimed to be within 0.05pH.

The pH buffer solution powders are mixed with 250mL of (preferably distilled or deionized) water, and the resulting solutions have pH values of 4.00 (red), 6.86 (green) and 9.18 (purple) when at 25°C. The packets also have a temperature compensation table on the back so you can adjust them accordingly, however in our opinion the differences between 20-25°C (room temperature for most water) is almost negligible for brewing, so don't stress too much about your calibration water temp - just make sure it's not freezing or straight out of the fridge.

pH buffer solutions laid out and ready for mixing and calibration

The pH meter only comes with a single set of calibration powders, but additional ones can be purchased for AU$3.50, not particularly expensive so we always keep at least one spare set on-hand and ready to go.

The general consensus of storing these buffer solutions (once they've been mixed with water), is they'll keep for 3-6 months but we've kept them longer than this and found them to still work and be accurate. Keeping them stored in the fridge can help promote their longevity (but make sure you take them out and let them warm up to room temperature before using for calibration) - and as long as the solution is clear, it should be good to go. But given the price point these are at, replacing them once or twice a year shouldn't be a huge financial burden anyway.

To actually perform a calibration, remove the cap from the pH meter and turn it on by pressing the On Off button. Submerge the electrode in the buffer solution, give it a gentle stir and wait for the reading on the screen to stabilize. Press and hold the Cal button for 3 seconds and then release - "CAL" should then flash on screen. The meter is pretty clever and automatically knows what buffer solution you've submerged it in for calibration. It will display the current reading for 1 second, followed by the detected buffer solution value for 2 seconds, and will then flash "SA" on the screen (we're guessing this means "Save") and then the calibration is complete and it goes back into measurement mode.

An example of the calibration screen

Repeat the process for the other two buffer solutions, and you've then got a calibrated pH meter ready to go!

Using the pH Meter in Brewing

We've used our KegLand pH Meter for a number of brew days and have been very pleased with how it performs. We don't have another pH meter we could use to test the accuracy of this unit, but what we can say is that in every batch we've made, our readings have always come within a few points of what our brewing software (Brewfather) expected - based on our source water and grain bill. Our measured source water pH values have also closely matched what the expected values are based on our water quality reports from Sydney Water.

We don't want to go into too much detail around the role pH plays in brewing, but what we can say is that if you don't adjust your brewing water pH, the pH value will likely be too high and you'll extract more tannins from the grains, leading to astringent flavours ending up in your beer. It's important you treat and adjust the pH of your mash and sparge water. When we first started out we neglected to treat our sparge water and quickly realised this was a mistake!

Our untreated tap water had reading of 7.4 - far too high for brewing

The "sweet spot" for the pH for most beer styles is between 5.2 and 5.6, so after mashing in we let the grain bed settle for 10 minutes before taking a sample for our first reading. The KegLand pH Meter features automatic temperature compensation too, so the sample doesn't have to be at a particular temperature before measuring, but as we've previously mentioned, we'd recommend cooling down the sample to (preferably) somewhere in the 20°C-30°C range.

We take a small sample in a glass then sit the glass in a bowl of ice water. Given the relatively small sample size you need for a reading, it doesn't take too long to cool down in our experience, and after submerging the electrode in the wort, we've generally got a stable reading on screen within a matter of seconds.

Final Thoughts

There's no disputing the importance of pH when making beer, so if you're not not measuring the pH of your water and wort, you really should be. The KegLand pH Meter is an affordable and easy to use unit that will no doubt suit brewers of all skill levels. It has all the features you would need in such a meter, and importantly it has a replaceable electrode component meaning you won't need to fork out for an entirely new meter when the electrode inevitably starts becoming problematic.

Don't be deterred by the maintenance required on such a device either - they're a little more robust and resilient than you probably expect, as long as you treat them with a little bit of care. It's definitely worthwhile in our opinion to spend a bit extra and get yourself the storage solution, some extra calibration buffer solutions as well as a spare electrode to have on hand. Even with all this it comes in significantly cheaper than many other pH meters on the market, that probably don't really offer anything above and beyond what the KegLand pH Meter can do.

You can get the KegLand pH Meter from the KegLand website - currently selling for AU$36.


Related Articles




No comments:

Post a Comment