How big of a difference is there between a pressurised and non-pressurised portafilter?

Question

I have been trouble shooting some of my own espresso and realised that my lower-end machine might just be unable to make a better shot due to having a pressurised portafilter. So with that I wanted to find out what real differences having an unpressurised portafilter there are compared with a pressurised one.

For those interested, my current espresso problems are as follows:

I manage to get the grind to a size where I'm noticing good thin mouse tail pours but the lack of thick, golden brown crema makes me think I can get a better shot.

I've read that light coloured crema or thin crema is a symptom of underextraction, depending on the length of the shot (where mine was in and around 20 seconds for a double shot, so relatively fast). I then ground finer and the extraction immediately changed. The mouse tails disappeared and the extraction was fast, almost instantly blonding within a second of the extraction. Liquid was not pouring out extremely fast but in comparison with the slower previous extraction it was relatively fast. I tried to continue to lower the grind size to attempt to slow the extraction but to no avail.

Could this be a problem with the pressurised portafilter?

Answer 1

Pressurized portafilters either restrict water flow or require a certain buildup of pressure before the espresso spills out the bottom of the portafilter.

So there are several problems with that taste-wise in espresso. The resistance is now not in the ground coffee itself, but below it. Additionally, if your coffee is ground finely and uniformly in a good espresso grinder (as one would for a non-pressurized portafilter), this sort of portafilter will result in too much resistance and thus a slow, over-extracted shot. It can also make your crema look a bit odd because it can emulsify some of the oils in your extracted shot (depending on the design of the specific portafilter).

Essentially the requisite grind size to produce acceptable espresso using a pressurized portafilter is much larger than that of optimal or delicious espresso.

This sort of portafilter does have its upsides, though. If you don't have access to a quality espresso grinder, and you are using either store-ground beans or imprecisely/more coarsely ground beans, a pressurized portafilter can make acceptable espresso from them whereas the results in a standard portafilter would be very watery and underextracted.

Answer 2

A pressurized portafilter, from what I understand, is a way for an espresso machine that does not provide a high enough amount of pressure (a typical industry grade machine pushes about 9 bars of pressure), and to still be able to emulsify the oils in the coffee - creating crema. First off crema is a terrible interpretation of espresso - use your pallet always! If it's underextracted, you will taste it. Then as you get dialed in, you can use the phases/color of crema to tell you information as it pulls. But with a lower-end machine - a pressurized portafilter is about as good as it gets until you spend more money. Espresso looks beautiful, but looks can often be deceiving.

Answer 3

In case this question still lingers on yours or other users' mind ... Pressurized PF is not PS, so to speak, as long as the whole setup is operated well, including expectations of your own tastebuds.

1) First of all, get the FRESH COFFEE. Even preground, espresso grind, bricks could work ok if reasonably fresh (if you can tolerate too much Robusta). Older or stale coffee won't yield much crema.

2) Make yourself a cup just with freshly boiled water, right in a cup, kind of a la Turka (2tbl spoons or so per 6oz). Do you like the general flavor? You'll see some crema too, the fresher the coffee, the thicker the crema. If not, get other coffee beans.

3) Next, make sure your machine gets the water HOT ENOUGH (over 90C).

I assume that your machine is able to build up enough pressure to open up the flow through your pressurized PF.

4) Now, you should time how soon you get the flow after turning on the pump with EMPTY PF, that is no coffee in the basket at all. This gives you idea how long at minimum the coffee would brew while locked up in the basket. It would only continue to brew more after the flow begins.

5) Then, the trickiest part - ask yourself what sort of EXPECTED TASTE are you chasing. It's not trivial, many of us are not familiar with "true" espresso. Not only because it's subjective, but simply due to lack of available choices out there to compare. Lots of cafes standardise to the balance for the milk-based drinks, which masks a lot of flavor details. The result is your palate simply may not be "calibrated" for the raw shots.

In case you're just developing your taste, get some help from your equpment to taste some variations!

6) Load your PF to the top of the basket WITHOUT HEAP. How many tbl spoons? NO TAMPING.

7) Pull the usual shot, time how soon you get the flow. Stop once the flow color is "beige" off-white.

8) EVALUATE. Any difference in the time vs. empty basket? How 'good' is the resulting brew (bitter, watery, strong, smell vs. the dry grounds) ? Any crema difference vs. direct in-cup brew (color, thinckness, coverage)?

If too bitter, stop the flow sooner (remove the cup). Time it when the flavor is good for your taste. If too accid...your water may be too cold or just let it flow longer.

Is it enough volume for your liking? Personally, a single shot volume (1oz) is not enough for myself, I like sipping it, not shooting.

9) Next, add MORE COFFEE, that is heaping it by one more teaspoon. Still no tamping, just level it a bit, tap-tap, or tamp lightly to fit just below the brim.

10) Do the shot. Evaluate.

Eventually, you'll figure out the amount of coffee you need to fit into your basket and how much tamping needed/possible. Also the results your setup can produce... Hopefully to your taste. And, well, more crema, if that's what your tastebuds ask for, though mostly it's just visuals, unless it's sippable before it gets smeared over the walls of the cup.

Another variation to try is PRE-INFUSION, basically delaying the full flow (if your machine allows you to interrupt the pump). This lets the coffee grounds expand/bloom a bit (3-5sec) before the gushing begins. Just compensate this by stopping the main flow sooner.

Variating the grind is more of fine-tuning, but you'd need a capable grinder. Btw, compare the preground coffee to what your grinder deems 'espresso', chances yours is coarser and dustier.

Anyway, espresso is no magic (mostly), it's just another way of having a taste that you enjoy. Find that taste! Make it repeatable. Keep your taste buds curious :)

Pressurized PF should help your journey, it's kind of equalizer, especially with the setup that you currently have. Espresso should be 'affordable' and liberating, otherwise it's just more viable to buy it directly from a cafe and barista that you like :)