Espresso is brewed somewhere around 9 bar (1 bar is equal to atmospheric pressure). Consumer and most prosumer espresso machines use vibratory pumps (often called 'vibe' pumps) to achieve the brew pressure. The problem is that vibe machines create approximately 15 bars of pressure so in order to reduce the pressure consumer machines in the medium price range have over pressure valves (OPVs) installed that limit the brew pressure to either 9 bar or 11 bar (if the machine is rated for E.S.E. pods) in more expensive machines variable over pressure valves are installed that allow the user to change the brew pressure to their liking.
As a follow up to part 1 on moonlighting as a freelancer while being a student I put together some tips and tricks for anyone in the same boat :
Here is a quick video I made of me pulling two shots of espresso from my non-pressurized Starbucks Barista (Saeco Via Venezzia) espresso machine
I am currently a full time student studying engineering (Civil) at the University of Manitoba…but, I am also a freelance web developer. And in my experience, I’ve discovered the following pros and cons of leading this interesting double-life.
There are several great reasons why being a web developer while at school is great:
Alright, so this morning I left my milk frothing for a while during which I was doing something else. When I looked at the frothing thermometer temperature gage I noticed that it was about 15*C above the scalding point. So I thought I had burned my milk but didn't so something was off. Then I took out my digital meat thermometer and there was a big difference between the readings.