Hi all,

I've just received my bottomless, non-pressurized portafilter and tried making a couple of espresso shots. Some were a complete disaster, some slightly better, but still rather bitter tasting. It's pulling the right ratio e.g. 15g in 30g of espresso out, but it's doing so in 13-14 seconds. What's the next step? Harder tamp? Finer grind?

Many thanks

Try grinding finer. You shouldn't use tamping pressure to alter extraction times, use a consistent tamp and that's one variable out of the way. Also the right ratio for you may not be 15g to 30g so experiment on longer and shorter yields but the extraction time of 13-14 seconds is a bit quick.

 

This is something I'll have to wait a little bit longer to change, as I won't be getting my Pharos grinder until the end of the month. Currently stuck with pre-ground espresso blend from a local roaster so I suspect that's the main issue?

 

I've just switched back to the pressurized basket for now and having an espresso grind has made a huge difference to the brew time with that. It used to be a similar 12-14 seconds but now it's around the 20 second mark, so once I have a decent grinder and can take the grind down even finer I think I'll be able to get quite a significant improvement.

One other thing I noticed with the non-pressurized basket is that there were some fines getting through the basket. Is this normal for a non-pressurized pf or does it mean the pre ground espresso coffee isn't great?

 

One other thing I noticed with the non-pressurized basket is that there were some fines getting through the basket. Is this normal for a non-pressurized pf or does it mean the pre ground espresso coffee isn't great?

Yes, it's normal for a modicum of fines to sneak through the basket. This also happens in pressurised baskets, and can lead to the output hole becoming blocked.

 

Without changing grind size you've very limited control.

Perhaps greater yield and a cheeky old nutation of the grounds may help

 

With no ability to change grind, then the 15 grams or more or less is only your viable change.

Seen a YouTube which tried to be 'scientific' about the pressure of tamping and apart from not being flat it made little difference.

So change your yield aka 16g in 20g in 🤷‍♂️