I watch too many coffee YouTube videos...
One of the hazards of being in the coffee industry is being sucked into the endless social media maze which surrounds our favourite caffeinated product. I've recently been watching some YouTube videos produced by Lance Hedrick. He's very popular. The video I watched yesterday focuses on the impact of portafilter aspect ratio on the quality of espresso being produced.
Aspect ratio is the ratio of an object's width to its height. A square, by definition, has an aspect ratio of one given that its width and height are identical. Most of you reading this will have coffee machines whose portafilter baskets have a diameter of 58 mm. That's the industry standard. Almost all of your local cafés will have La Marzocco or Kees van der Westen machines using 58 mm portafilters. Some manufacturers, however, use smaller diameter group heads. There are portafilters out there which are 54 mm in diameter all the way down to 49 mm. My manual Strietman lever uses 49 mm portafilters.
Lance's contention is that given the same weight of ground coffee, a smaller diameter portafilter basket will, of course, have a smaller aspect ratio. The height of the portafilter needs to increase to compensate for its reduced width. It is his belief that a narrower, taller coffee puck requires a slightly coarser grind and produces a better espresso extraction. He uses a Sworksdesign stepdown filter basket which is machines to fit in a 58 mm group head and reduces the puck diameter to 49 mm. He prefers the espresso out of the stepdown basket to the standard Sworksdesign filter basket.
This got me to thinking about all of the portafilter baskets that I have.
The above photo shows only my 58 mm baskets. It doesn't show the 49 mm baskets that I also have. This is all further proof that your devoted correspondent is plain crazy.
The photo at the top of this blog post shows a side on view of just my range of VST baskets. They have capacity for 7 g, 15 g, 17 g, 18 g, 20 g, 22 g and 25 g of ground coffee from left to right.
I typically use the 22 g basket but hadn't used the 25 g basket recently. It's the quickest way that I could think of to test the impact of aspect ratio. This doesn't take into account a myriad of other factors though... absolute dosage amount obviously goes up from 22 g to 25 g, and it's highly unlikely that the hole pattern in the basket is exactly the same. Let's ignore these minor inconveniences! Apologies to the truly scientifically minded here (most of you).
Completely subjectively, it was lovely tasting the output from the 25 g basket. Very full bodied, lovely acidity and, to my mind, a better cup than the 22 g basket. I'll keep going with the larger basket.
To learn about filtering espresso click here
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