Brewing the perfect beer comes down to some key elements. One of the most important is temperature. Measuring the temperature during the brewing process happens when fermentation takes place, which is the most critical.
Was the temperature of the liquid kept at the right level during fermentation? Was it contaminated when assessing the temperature? These are main questions asked when assessing whether a beer is finished processing and ready for drinking.
Those are the types of factors that will determine whether the beer is good to sell and drink or if it should be given away or disposed of.
What is a thermowell?
A thermowell is a cylindrical fitting used to protect temperature sensors installed when measuring the liquid in the wort. Or in the subject of beer, it protects the thermometer when measuring the temperature as well as protects the liquid from contamination. The thermowell acts as a barrier between the device measuring temperature and the liquid as well as the liquid from the outside air.
Why is that important?
Well, it keeps the thermometer from getting sugar residue on it making the measurements inaccurate and hard to clean. It also protects the liquid from contamination from the air outside the wort. Both of these can cause the beers flavour to completely change at the end of the fermentation process.
In appearance, a thermowell consists of a tube or pipe narrowed off at the end of the device for protection and to seal the product. A temperature sensor such as a thermometer, thermocouple or resistance temperature detector (RTD) is then inserted in the open end of the tube, which is usually in the open air outside the process piping or vessel and any thermal insulation – or in the beer brewing industry, the wort.
What thermowell to purchase?
When purchasing a thermowell, stainless steel is the most ideal material because it quickly attains the temperature surrounding it and it won’t contribute to different or even ‘off’ flavours in the beer.
When choosing a thermowell, there are three types which are: screw in, flanged or welded, which can be designed to match the temperature gauges used in the process of beer. Thermowells can be machined from solid bar stock, or fabricated from the pipe, but most can be made to suit any specification.
When brewing, a thermowell is highly recommended because the temperature element needs to be inserted into the content where pressure is present or when the content is in danger of being contaminated.
They also play a key role in the brewing process as they allow the most accurate temperature management whilst protecting the sensor, ensuring the best quality of the beer is produced.
How do you use a thermowell in brewing?
To accurately measure the temperature inside the wort, the temperature probe must be in firm contact with the bottom of the thermowell. Even the slightest gap can change the reading, making it inaccurate.
The best way to ensure this is to measure the inside length of the thermowell, you can do this using a skinny measuring tape or some stiff wire. If the probe isn’t the right size, don’t try and fix it – it is recommended to purchase the correct probe.
Once it fits and you have secured the thermowell, it is a matter of threading the probe down the tube to the bottom, in which then you will have an accurate reading.
A thermowell is a key tool needed to make and brew the perfect beer. It is essential to ensuring the perfect temperature is measured by using your thermometer or any other tool you use to measure.
The thermowell protects the temperature sensing instrument, the beer inside and your heartache if you don’t get the fermentation right. This tool is a small price to pay to ensure the right flavour for your beer.