I love this thread! If arguing about sound quality from audio gear gets boring, switch to arguing about making coffee. And if arguing over making mere coffee gets boring, go straight to arguing about making espresso.
Is there such a thing as coffee infused snake oil? Where are the independent scientific tests showing that 30 lb tamping tastes better than 20 lbs?
Good coffee, as any coffee snob will be glad to tell you, contains no snake oil or any other contaminant. However, that leaves us open to the snake-oil-like effects from different grinders, brewers, espresso machines, etc.
@tonyE - stop buying Costco beans. They are likely long past 2-3 months of reasonable beans shelf life. If you can't roast yourself, find a local roaster.
I see I have taught you well
. The differences between fresh roasted or stale coffee are by far greater than any grinding or brewing method. In fact, I'd argue that coffee 2-3 months past it's roast date has been stale for at least a month or two. I like coffee beans no longer than 2-3 weeks past the roast date. That's why I roast my own. However, I have been able to buy good tasting roasted coffee older than 2-3 weeks. I don't know how commercial roasters do that, but I do admit it exists.
you should provide around 30 lbs of pressure to tamp your coffee properly for espresso. they sell "
calibrated" tampers which are similar to torque tools, click then you reach the magical 30lbs of pressure.
I never knew such a thing as calibrated tampers existed. But I'm not too surprised. On Amazon, you can pay $10 for a simple tamper, or as much as $100 for a 'calibrated' tamper.
In defense of this apparent 'snake oil', many people, including myself, fail to understand just what the effect of steam pressure has when making espresso. My daughter, who worked as a barista for a while, once explained all this to me. (As a dedicated 'man splainer', I was extremely proud that my daughter could out man splain me.)
Coffee making commonly involves mixing ground coffee with hot water to extract the coffee flavors and cafeine. In this process, the amount of ground coffee and hot water obviously matter. But so does the length of time that they are mixed together. A lot of the coffee flavors are only partially soluble in hot water. As a result, the time of exposure also matters.
Espresso introduces a new variable, steam temperature at high pressure. Steam is sent through ground coffee at very high pressure, about 10 atmospheres. That's 147 pounds/in² (psi), or 1013 Kilo Pascals (KPa) for those metrically inclined. At 1 atmosphere pressure, steam is 100°C (212°F), but at 10 atmospheres steam is about 121°C (250°F). In fact, at this pressure it isn't steam, it's superheated water. This elevated temperature has a very large effect on the extraction of coffee flavors. The quantity and quality of extracted flavors are quite different. Some people love this difference and will pay good money for good espresso.
At 10 atmospheres pressure, there is a benefit from using coffee uniformly ground very fine – hence the need for different and more costly grinders. But, unless the grounds are packed firmly and evenly – into a so-called puck – the high pressure steam/water finds ways to channel through the puck without fully wetting and extracting all the grounds. There is a need to pack the grinds firmly enough to prevent channeling. But if you pack too firmly, you can also block good extraction. This packing, or tamping, is often how a good barista stands out from an amateur. And, I guess, this is why those calibrated tampers are now sold.
All this, the cost of high pressure espresso makers & espresso grinders, as well as the learning curve for tamping the puck is why I haven't bothered with making espresso at home. I like drip coffee made from fresh roasted coffee well enough. For others, YMMV.
