Grinding from Frozen Vs Unfrozen Update
I have been running a series of tests, using the same beans, same grind, same dose, same basket, same temperature, same pre-infusion, same brew ratio. Just grind from unfrozen vs frozen. The beans were stored in very small sealed single shot jars.
I have done 4 sets of paired shots thus far, over a number of days. In virtually every case, the frozen shots ran significantly faster. Like 15 seconds faster!
And …. every ground from frozen shot had slightly but noticeable less body and less strength than the ground from unfrozen shots. And the ground from frozen shots were noticeably more bland.
I then poured two sets of unfrozen vs frozen shots, but went to a one number finer grind on my NZ for the ground from frozen shots. In both cases, the flow times were close to the same.
And in both cases, the ground from unfrozen shots had somewhat more body and strength. And the ground from frozen shots comparatively tasted a tad bland.
Conclusion: From this very unscientific test. I prefer the taste of ground from unfrozen shots.
Other Changes
I’ve also just now been changing a couple of things in my dose and distribution. I improved my WDT technique to use the small circle moves that Lance Hedrick demonstrated in his video, which eliminated the holes that I frequently seen in the top of my puck.
I also tried 18.0g in my 18g IMS basket (see headspace analysis below), using beans that have not been frozen, with better WDT technique. All while maintaining the same brew ratio of 1:1.5.
The Result: Good body, good strength, decent flavour emerging and decent length; my best tasting shot (with my Lelit E and NZ) to date.
Getting there.
Might pop in my IMS screen and grind finer, just to drive me nuts 🤪
And Headspace
I used calipers to check the headroom that I have, using my IMS 18g basket on my Lelit E, and my current City Roast decaf blend. I measured that there is 9.5 mm from the top of my basket rim to the bottom of the flange on my bottomless portafilter. I also noticed that the top of the spiral that holds the portafilter on my Lelit E is even with the screen. So a fully tamped puck that is 9.5 mm below the rim of my basket will touch the surface of the Lelit E screen. Or so it seems.
Accordingly, if I add 2.0 mm (the thickness of a Canadian nickel) for headspace, the top of my fully tamped puck would need to be 11.5 mm below the top of my basket rim.
As my basket has a 22.1 mm interior depth, my puck depth (top to bottom) should ideally be 10.6 mm. Supposedly.
Interestingly, if I load this basket with 18g, I get: about 10.3 mm of puck depth and 2.3 mm of headroom. Give or take.
So maybe IMS designed their 18g basket to fit 18g and allow for sufficient headspace. Duh 🙄
Why all this faf? Just wanted to see how much headspace I was getting. I’ve been dosing 16.5g in my 18g basket, in order to allow for sufficient headspace. I now realize that I can easily dose 18g, and probably still get sufficient headspace.