If you are starting your own all-grain brewing adventure then you probably already realize monitoring your mash temperature is vital! Having the right type of thermometer could make or break your brew day, so doing your research is essential.
Brewing thermometers come in many different types and models, the most efficient being the digital versions. If you are brewing on a regular basis then consider buying an instant-read or infrared thermometer for your home brewery. Basic glass and probe models are best for beginner brewers.
However, not all thermometers are made equal, nor are all mash tuns for that matter!
Below I’ve compiled everything you need to know about getting the right thermometer for controlling your mash’s temperature, so read on for more information.
Why monitoring heat during the mash is important
Whether or not you are an avid brewing scientist or not, you understand that something important happens during the mashing process and that a particular temperature range is key. In fact, without heating grains to the ideal mashing temperature, making beer in the way that we do would be impossible.
In a nutshell, what we are trying to do during the mashing process is to convert the starches within malted grains into fermentable sugars. This is done by activating the enzymes already present in the grains through the use of exact temperatures. For the majority of beers, that ideal mash temperature range is between 145°F and 156°F (63°C and 69°C).
The period when most of the sugars are produced, known as the conversion step, will vary depending on the approach you take to mashing your beer. There are several ways to mash, from single-step mashing to decoction mashing, but that’s a topic for another article. What I’m most concerned with for now are the actual enzymes that brewers exploit during the mash.
Alpha-amylase & Beta amylase
Alpha-amylase is most active between the range of 154°F–167°F (68°C–75°C) and this is the enzyme which does perhaps the most work. It is able to break down starch into very usable maltose sugar as well as other sugars that aren’t so fermentable but can add to the body and mouthfeel of your beer. f course we’re talking about dextrins here.
Beta amylase (130°F–150°F (54°C–65°C) )is perhaps not as useful as its alpha cousin in producing a diverse range of sugars, but it can chop off single maltose molecules from the ends of the complex sugar molecules which Alpha-amylase produces. This way not all those unfermentable sugars are lost nutrients to the yeast later on.
So, depending on your beer recipe you will try to activate more of each type of enzymes for a slightly different finish to your beer, or even to make use of both types by performing a number of temperature steps during your mash.
With all this being said, it’s clear that having accurate information about your mash temperature is important, so getting the correct type of thermometer is crucial.
For more information on mash tuns, check out my detailed article on this topic right here.
Low-tech
Brewing beer doesn’t mean that you need an advanced degree in rocket science nor does it require fancy digital equipment. People have been brewing for centuries with low-tech kit and there is no reason why you shouldn’t do the same.
Glass thermometer
This are the staple of any starter kit and perfectly proficient in monitoring the temperature of your mash, wort and even beer.
Most brewing thermometers made from glass (or even some plastic ones) contain some form of alcohol inside which actually measures the temperature of the liquid it is placed in.
The only issue with using these types of thermometers is that they really need to be fully submerged in the mash, or what have you, otherwise, the alcohol inside them can start to vapourize. If this happens too frequently small bubbles can form in the reading tube and muck up your readings.
Of course, glass is also very fragile and you could suddenly be without a thermometer during a crucial stage of your brew day.
Probe thermometer
For brewing, these are an excellent choice as most models come with a clip to fix the thermometer to the rim of your mash tun (or brew kettle) and come with a dial indicator on top.
The main advantage of a probe-type thermometer over the common cylindrical glass model is that you don’t have to fully submerge the entire unit. Also, it’s much easier to manoeuver the thermometer about and check the temperature of other areas of the mash ensuring an even heat distribution throughout.
This design also comes in a digital format but works in pretty much the same way with the same advantages.
Built-in Mash tun thermometer
Several mash tun models, as well as many brew kettles, come with thermometers built into them. They are also a dial thermometer set up with a probe that extends into the vessel.
Generally, these are a great way to monitor the temperature of your mash but they can be misleading. If, for example, you have thicker areas of your mash the temperature could be vastly different from other parts of the mash. A built-in thermometer will not be able to show you this as it can’t be moved about.
However, if you stir your mix properly and ensure that it has an even consistency throughout, then you can certainly rely on this type of thermometer to give you a very accurate account of the temperature throughout the mashing process.
Adhesive thermometer
This type of thermometer is great for fermentation but is next to useless for mashing unless you are doing it in an uninsulated metallic pot.
In most cases, however, sticking an adhesive thermometer on the side of your mash tun wouldn’t indicate the actual temperature inside it. Even if it could detect the temperature through the isothermic insulation, these types of thermometers aren’t not very accurate and usually have a display range of 2 or more degrees.
I would advise that you invest in another type of thermometer for your mashing and keep these beauties for your carboy instead.
New to homebrewing? Please feel free to read my ultimate guide to brewing beer at home and where to start.
Hi-tech
Although not every brewer needs to use the latest gadget to get the best beer, some piece of kit can be very affordable and can save you lots of head-scratching on brew day, digital thermometers are one of them.
Instant read
If you are a hi-tech home chef, you’ll be familiar with these types of thermometers which come in handy for cooking tender meat. They are also ideal for brewing, especially mashing.
The main advantage of this type of thermometer is that you don’t have to wait any time at all to get the temperature reading for that area of your mash. This means that you can quickly open your mash tun’s lid, get the reading and reseal it without losing too much head as you would with a traditional thermometer.
Infrared
These types of thermometers are just amazing, not least for the price tag they go for! Not only will you get a very quick reading on your mash, but you don’t even need to place the thermometer in the mash tun. Just aim, shoot and read.
In the same way that an instant-read thermometer avoids exposing your mash to colder outside temperatures, the infrared model limits this exposes even further. All you need do is crack the top of your mash tun’s lid, point the thermometer through the gap and get you reading without even opening the lid fully!
Bluetooth
Now even your brewing system can come with Bluetooth installed so that you can connect to it wirelessly and control every stage of the mashing process.
If you invest in a brewing system such as a Grain Father, (check out this beast on Amazon for the latest deals) then you can control everything it does, including getting the thermometer readings, on the specially developed app on your phone
Recommendations
Below are the recommendation I have personally and some I’ve been given by several prominent home brewers in the community.
Basic brewing thermometer
This is your no-thrills basic thermometer which will serve you well for much of your brewing career, it’s always worth having at least one of these knocking around the home brewery just in case you need it. Check out the great deal you can get for this on Amazon.
Probe dial thermometer
If you want something which won’t involve getting your fingers close to your mash (or boiling wort) is this step up from the basic design. It’s cheap and practical as well as very efficient. Get yours on Amazon today and have it delivered fast.
Instant read thermometer
For any serious brewer, this is the model of thermometer to go for. It takes all of the work out of the process of monitoring your wort’s temperature as well as the waiting time. There is a lot of choice on Amazon, but this is the one I would get personally.
Infrared thermometer
If your mash tun isn’t an insulated cooler then perhaps you need to limit the exposure of your mash to the cold air while monitoring its temperature. If that’s the case, then perhaps going for an infrared thermometer over and instant-read model would be best. I recommend this model which you can also find on Amazon.
Mash tun with a built-in thermometer
If you are very new to all-grain brewing, then you may not even have settled on a mash tun, which is required for mashing unless you go down the BIAB route. For more information on what this is, check out my full article here.
Below are just two examples of good mash tun setups, one is based on the cooler design and the other is a stainless steel model.
Northern Brewer – Insulated Cooler
I really like Northern Brewer as they make some really good kit, this comes with a handy built-in thermometer which you may want to pair with either an instant-read or infrared thermometer to ensure a consistent heat throughout.
See the latest deals and availability on Amazon right now.
Chapman 15 Gallon ThermoBarrel
If you want to stick to stainless steel construction due to its durability and ease of cleaning, then the ThermoBarrel, so my fellow brewers have told me, is a good option. However, personally I much prefer the cooler-type model.
It also comes with a built-in dial thermometer but I still recommend having a hand-held model or clip-on model just to check various areas during the mash.
Check out the price and more details about this model on Amazon and benefit from some home delivery!
