The product is moving into a different territory, though. I doubt these guys even know how to pull a proper espresso shot as a baseline for the test. I'm sure you can grind espresso coffee beans to a powder and just shake it until it achieves a flavor similar to espresso, but that doesn't mean the resulting drink can really compare to something that was brewed at the right temperature and pressure.
Technically you can also buy a bottle of grape juice from the grocery store, let it sit on the kitchen sink with a yeast lock for a few weeks and call it wine, and technically it even is, but it's also going to taste quite shitty.
> I doubt these guys even know how to pull a proper espresso shot as a baseline for the test.
You could just read the linked paper?
> Esp was prepared using a Sanremo Cube espresso machine. Brewing parameters were standardised following the supplier's guidelines: extraction time of 35 ± 3 s, pressure of 9 bar, and boiler temperature of 122 °C, with the corresponding group-head temperature of 94 ± 1 °C. A total of 21 g of ground coffee (GS = 2.6 ± 0.1; ∼262 μm) was placed in a ridged coffee basket and tamped using a constant-pressure tamper (MHW Flash Constant Pressure Tamper 2), applying 13.6 kg of force. The BR was reduced from 2 to 1.7 following the recommendations of the coffee roaster for better flavour (1 g of coffee grounds yielding 1.7 g of coffee brew).
1:1.7 is a bit short for my preferences (I like longer shots, usually aim for ~2.5); but otherwise that sure sounds like a pretty good double to me!