RNAV wrote:In DaveC's video review of the anti-popcorn device, he mentions the device regulates the flow of beans entering the burrs. Hence, you have improved uniformity of the grind size, and he goes on to mention you'll need to grind 4-5 notches finer after installing the device. Sounds like this is what you're experiencing.

http://www.youtube.com/watch?v=BsxUzpH0VIw

Yes that's correct and of course the coffee doesn't come out any finer, it's just that when flow is regulated the packing effect within the burrs that creates finer grind but wider distribution is reduced. This means the overall fineness remains the same (as without the disk) when you adjust finer but with reduced distribution around the grind level.

You can test this for yourself.

I didn't put the results in the mini write up on the review site because it was a bit geeky and I don't know how much value the normal reader would have got. You can also try this first test with any grinder you are single dosing, not a Niche to see what sort of variance you get, which of course relates to the grind distribution.

Method (with the Niche NFC disk in place, or one made to almost exact dimensions)

17g coffee added to Niche. I split the grind output between 2 containers and ground for 8.5 seconds in the first before swapping (this might vary a tad depending on mains voltage and speed of the Niche), then swapped the grind cup for a small plastic tray for the remaining time, the grinder was constantly running and not stopped for the test. I repeated this so I had 2 splits, the first and second half of each grind.

This gave equal doses of approximately 17g (within 0.3 of a gram). I repeated this process 4 times to have 4 tests. Rather than post an average which can be misleading. I will post 1 set of results, the rest were very similar, to within a second or within 1g of extracted espresso weight. It's tricky to get the extracted espresso weight right on the button, as my scales have a slight delay.

33.4 coffee out, shot timer 26.8s..........1st half (17g coffee)
32.6g coffee out shot timer 27.4s..........2nd half (17g coffee)

17g coffee. 2 grinds 50/50 split.

Machine used Minima, constant pressure set to 9 bar....no profiling used, extraction temperature 93C

The taste of the coffee was the same (to me) in each case. People are welcome to try this and confirm what I found. I'm not going to bother with 3rds because it's super tricky and 50/50 splits do show if there is a significant difference and would have seen much more variance. So the device is working as it should. In fact it would be tricky on other grinders, simply because of retained grinds, fortunately that's not really a problem with the Niche.

Then as a control

With exactly the same grind setting as the test above and no NFC disk, results were typically:

54s shot time 32g output (17.10g coffee 1st splits added together)
33s shot time 32g output (16.84g coffee 2nd splits added together)

Quite a clear difference...obviously the 2nd splits were 33s because there was still some gradation in the grind at the 8g point to an unknown level below 8g? Certainly after 8g, the variance is much less, which would be in line with the reasoning why this happens.

Anyone with a Niche can do these tests and when they get the NFC disk try the tests with those. I've used enough coffee doing them and I'm happy about what's happening and that it helps a great deal...for sure timings might differ a bit with different coffees, but the effects should be the same. You need approximately 350g of the same coffee to do a test run of 4 tests with and 4 test runs without the disk (and allow for any mistakes, plus normal 18g shots with no splits).

When I do reviewing and testing I actually do quite a lot more testing that I ever bother publishing