Widget Pressure

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Widget Pressure

Inside a can of Guinness and a few other beers, a plastic widget releases pressure when the can is opened and exposed to atmospheric pressure. While the process is explained briefly and to the extent that a typical beer drinker cares to know on the can, there are a few other compelling technical aspects that someone involved with or interested in pressure sensing might want to know.

For one, the widget is a patented approach to solving a problem that a canned stout beer, like Guinness, has compared to typical lager or lighter beer or ale. For the later types, carbonating the beer with carbon dioxide (CO2) is sufficient to give the beer its expected head when the beer is poured. In contrast, Guinness and some other beers are expected to have a smoother head. With a widget in the can, these beers have the desired, much creamier, longer lasting head that the draft version has.

The 3-cm diameter widget looks like a ping pong ball but it has a laser-drilled, 0.61-mm pinhole in it. In the canning process, in addition to filling the with CO2 and nitrogen (N2) supersaturated stout, liquid N is added to the stout at the end. The liquid N boils off during pasteurization, the top of the can pressurizes and forces the stout into the pod until equilibrium is reached at about 25 psi.

Mug of Beer with widget

When the can is opened, the pressure is released and the small amount of beer in the cavity rapidly escapes through the pinhole providing sufficient agitation to reproduce the tap handle character for the beer. Enough of the technical stuff. It’s time to verify the results.

Do you have a pressure sensing question? Let us know and we’ll address it in an upcoming blog.
Email us at info@allsensors.com

The Pressure to Make Great Beer

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities and you. In this blog we’ll discuss pressure and the role it plays in creating great beer.

The Pressure to Make Great Beer

Temperature and time play critical roles in the brewing process. In addition, commercial beer making involves the use of several pressure sensors to monitor different phases of the process.  Various stages of brewing, including mash and wort (the liquid extracted from the mashing process), require careful monitoring and a brew kettle may have gauges for operators.


According to one authority, “Most breweries use a steam-fired kettle, which uses steam jackets in the kettle to boil the wort. The steam is delivered under pressure by an external boiler.” Monitoring the pressure requires a pressure sensor. Other steps in the process flow are also candidates for sensing pressure. According to Wikipedia, steps in the brewing process include malting, milling, mashing, lautering, boiling, fermenting, conditioning, filtering, and packaging.

Automated processes provide greater consistency and control of brewing or any food processing and require electronic sensors.  Automation is even used for home brewing.  One product called the Brewtroller uses a proportional-integral-derivative (PID) controller or on/off switches to control heat outputs, pump and valve outputs.  It also employs a variety of sensors, including:

  • Six temperature sensors
  • Three optional volume sensors (pressure transducers) to measure the hot liquor tank (HLT), mash and kettle volumes
  • An optional steam pressure sensor for controlling steam heat

Another new product, Lyon Labs’ BrewNanny uses an automated seal to release the carbon dioxide produced when fermentation takes place and to prevent air from entering the container. The seal has an embedded 32-bit microcontroller, a pressure sensor to monitor C02 and other components to improve the home brewmeister’s product.


Source:  Lyon Labs

The BrewNanny displays brewing parameters in real time on the BrewNanny Dashboard through a web browser or custom apps for Apple and Android products.


Source: Lyon Labs

As in many industrial and medical applications, pressure plays a critical role in monitoring and control. With my own favorite brew in mind, Prost, Skaal, Cheers, Salute, Kampai or whatever your toast is — enjoy.

What do you think/Comments?
Do you have a pressure sensing question? Let me know and I’ll address it in an upcoming blog.
-Han Mai, Marketing Coordinator, All Sensors Corporation (hmai@allsensors.com)