Gaggia Classic E24 - Pressurized Basket - what to expect

Pressurized basket in espresso machine may sound great at first, but it is actually any good?

What is pressurized basket

It's a basket with one hole. And the only purpose is to reduce the flowrate of water. By creating resistance. But it's only a part of the resistance, the rest should be added by coffee.

While in a regular espresso basket, resistance is created purely by coffee. Which means to obtain a 9 Bar pressure you'll need to find the grind size and dose of coffee which creates it.

Otherwise you will have a high flowrate of water through the coffee and it will be impossible to get a good shot.

Problem of pressurized baskets

It's tempting to invest into a coffee machine and then - in a coffee grinder. Because you may think that it's possible to use ground coffee. But the thing is - there is no "espresso grind size". It's unique not only for every coffee, but for every coffee machine.

Gaggia Classic has a powerful pump. Without inserting portafilter the flowrate is around 8 grams per second. With the portafilter - it's around 5 grams per second. And for espresso we need to have around 1-2 grams per second. 

With the big grind size - you will not have resistance so your shot will run too fast. While in other machines, like Delonghi Dedica, this grind size will be the only option.

Gaggia Classic with pre-ground coffee

What to expect? It will depend on a coffee and the grind size. But here are a couple scenarios so that you know what to do and why.

Big grind size

I had a big grind size, coffee is basic (not a specialty). And it has dark notes like chocolate, nuts. The dose is 16 grams, that's the maximum which I can use with this basket. My shot time was around 15 seconds. And I got around 55 grams out. Which is ratio of lungo, around 1:3.4. 

So the coffee was pretty dark in flavor and had unpleasant intensity to it. What can be done to fix it? Smaller dose of coffee out! Less liquid. I ran the shot again, this time targeting to stop when it shows 40 on scales. So in fact I got 45 g out. It was more drinkable and took around 13 seconds. As you can see, the brewing time is short. Coffee was like from an automatic coffee machine.

Smaller grind size

I got the grind size from the roaster which they set the grinder to "Turkish coffee" when someone orders it. The result - still not enough resistance. Why? Because coffee was degassed. Ground coffee release CO2 way faster than when stored in beans. So the grind size needs to be even smaller than that. But the cup was nicer and more complex. Though, still under 15 seconds.

Specialty coffee

Since I'm not a fan of dark flavors in coffee - I used some good washed processed Colombian coffee. And targeted 1:4 ratio (lungo). And it was awesome. While it'll be a terrible idea to use a lower ratio, this one was pretty good. Because we have less "dirty" and unpleasant flavors which extracts too fast, we have a clean cup and can push it even further than 1:4 ratio. While with the basic coffee I'll go with 1:2 even though it's fast.

Pressurized basket with fresh ground coffee

This could be actually useful. I set the grind size which is slightly bigger than needed. And machine struggled to push it. The resistance from coffee and the basket was too high. So I stopped the shot when it was in ristretto zone (1:1 ratio, 15 g in, 15 g out).

The shot was perfect though it took 37 seconds which is a little big longer than I wanted. So the option here is to use less coffee next time and have a proper brewing time while having a higher ratio (like 1:2, espresso). Or make the grind size bigger.

Is it useless after all?

For me - yes. It has a "double wall" inside. Regular part of the basket pressed inside the basket with one hole. Which creates straight walls and leads to a terrible experience when trying to knock out the coffee puck after making coffee. Way harder to get it out than from a normal basket.

And with the regular basket I tried the shot of specialty coffee - it was still drinkable. So I would avoid using it at all costs. First rule of espresso - to get a good grinder. Here are the options:

• Timemore C3 esp (manual coffee grinder, pretty fast, lots of adjustments)
• Fellow opus (electric coffee grinder, not that loud compared to others)
• Eureka Mignon (pretty silent as well, purely for espresso)

At least now you know what to expect and possibly how to adjust the flavor of your coffee. And here is a specialty coffee for espresso.