The truth about espresso bar pumps
by Lucia Liang on Jun 01, 2023
The truth will set your espresso free
Even the world of coffee is not safe from its fair share of scandals, issues, problems, and misinformation! Often the scandals in question are regarding who invented or developed what coffee drinks. For example, who invented the flat white?
But the controversy we would like to address today is in regards to untruths about just how much espresso bar pump pressure is the best. As it turns out there are some brands out there who are advertising an espresso bar pump that administers 20 bars of pressure. However, this is overkill as the ideal unit of bars of pressure for espresso is not even close to 20 but is 9! In addition, it even goes to mention that a bar pump pressure of 15 is also okay for brewing! Let's get to the bottom of this one.
But what are bars?
When we say espresso bars, no we don't mean a trendy place where one usually stands and orders, maybe in Italian, before enjoying ones brew and heading out the door. The bar refers instead to the units used in the pressure pump when your espresso is brewed.
As espresso is brewed by having hot water forced through the grounds there is some unit of measurement used to describe just how much power is being administered during each brewing. Hence the term “bar”.
Bars themselves refer to a metric unit of pressure. 1 bar is about the same amount of pressure as the atmosphere at about sea level- so nothing too wildly intense. However, increase your bars to 2, and that's twice the amount of pressure one would theoretically experience at around sea level. Now, 20 bars would be 20 times the amount of pressure one would experience, and so forth.
Since espresso needs pressure to brew by forcing the water through the grounds at a high level of intensity for a short period one can see why espresso machine producers would advertise 20 bars of pressure. The reasoning is that the higher the pressure, the faster the brew. But other factors come into play when pulling shots of espresso, and usually, the amount of pressure slows down as it pushes down toward the grounds from the pump head.
Most of the time a lot of the initial pressure is lost while brewing and so only about 9 bars of pressure make it through anyway. It is also important to note that the ideal brew time for a good shot of espresso is 25 to 30 seconds rather than 10! That lower amount of pressure and certainly increased duration for pulling an espresso shot plays a big role in drawing out all the flavors, aromas, textures, and certainly the famous crema adequately.
The truth is out there
Some espresso machine producers will advertise 20 bars of pressure for their espresso pumps. But 9 bars is the ideal amount to shoot for. So don't be fooled by those bigger numbers, they all usually boil down to 9 bars once they reach the grounds anyway. So, with the truth out in the light, we hope you enjoy only the most honest of espresso shots!
- “How Many Bars of Pressure Is Good for Espresso?” Home Grounds, 4 June 2021, www.homegrounds.co/how-many-bars-of-pressure-for-espresso/.
- What Does 15 Bar Pump Pressure Mean | CoffeeEspresso.com. 22 Jan. 2018, coffeeespresso.com/what-does-15-bar-pump-pressure-mean/. Accessed 23 May 2023.