Yes, it needs to be coarser than the mesh screen size

But how much does grind size really matter for French Press?

I ask because I've spent alot of time trying to 'dial in' the right grind size for my Chemex & V-60 but yesterday I made a pot in the French Press, accidentally forgot to coarsen up the grind size but it still tasted great

What about the AeroPress? Does the grind size even matter for immersion methods?

Thanks

You can make French press with just about any grind (whether larger than the mesh, or not - fine grinds will sink quickly, you may not choose to plunge at all) as long as you can effectively separate the grinds from the beverage (this action itself can have a marked effect on flavour, beyond level of extraction itself) and you adjust the steep time to suit. I think for typical steep times, of a few minutes, somewhat finer grinds than usually seen for French press can work well. Though, as a brewing method, I like it because you don't have to time it to the second, so I normally use coarse grind and long steeps. Also, once it tastes good enough to pour, I don't really want to change the flavour by secondary filtering (though I have filtered French presses & Sowden brews through cones & the Aeropress with good results, so it's more a case of having a method, sticking with it & honing it).

Very coarse grinds in the Aeropress are likely to underextract, I have steeped for 50+ minutes inverted with coarse grinds and was only just getting in the ball park. Anything up to cupping grind can work.

"Immersion methods" covers a spectrum of brewers, once you have finished immersing, how you then separate the grounds from the beverage may skew the final result from specific brewer to brewer.

It's relative to the other brewing variables. It would matter quite a bit in nailing a particular TDS/Ext, but maybe less if you are going by feel and just want to enjoy the taste.

Both infusion methods have a flexible range of usable grind sizes because it can easily be compensated with varying steep times. With French Press, it needs to be coarse enough that the majority doesn't go through the mesh, but not too coarse that it always underextracts regardless of time.

With Aeropress, there's an even greater range but it still must be coarse enough that it doesn't clog (fine turkish grinds require a tremendous amount of force to press down) and fine enough that it can extract properly within a given time.

Considering that both Chemex and French press aim for 3-4 minutes of brew time, I'd say that it isn't coincidence that your French Press still tasted great without adjustment

What size mesh screen are you using? What is considered to be coarse and "fine". I am having a hard time finding just about what size most people here on the site are using?

Read James Hoffman's article about it. Very enlightening. We don't need to grind as coarse for French Press as tradition has taught us.

It also helps having a large blind tasting panel and a refractometer to back up your claims, rather than just standard "internet expert" blathering. Another reason why I appreciate what he does.

I'm sure there are excellent barista arguments for one grind size or another for FP brewing.

There's a different perspective though, more mechanical and less about taste nuance. If the grind is too fine, or too many fines are present in a coarse grind, the fines can pass through the FP filter, resulting in a murky brew; or, worse, can block the filter and cause enough pressure to build up to stop the press, or even shatter the glass carafe.

If the grind is coarse enough, and consistently sized, the filter(s) will glide through the wet mass easily and the brew will be cleaner.

We use the same grind for Espro press and cupping. As a point of reference that's a skosh finer than the recommended FP grind on a supermarket bulk grinder, and in line with what James Hoffman wrote. As a very obscure but more precise reference, that's "8" on the Trifecta dial of a Bunn G grinder ("9" which is three clicks finer, is recommended FP; while "5 + 2 clicks" works for Chemex/Kone, balance-beam siphon, and Aeropress).

We haven't used a "regular" FP since Bunnjira started crushing our beans, but I'll give it a try this morning.

Like James Hoffman, we find that allowing the coffee to steep does not harm the coffee. But, unlike Hoffman, we find that steeping time does alter the balances of tastes in ways which go beyond mere strength. However, most FPs allow the coffee to continue to "steep" -- although at a slightly slower rate -- as long as the grounds remain in the pot; even after its been pressed.

Like Hoffman, Linda likes cold coffee. Unlike my betters, I don't.

BDL