# Recommended sieve size for sifting coffee



## dsc (Jun 7, 2013)

I wanted to give sifting a try using cheapo "lab" sieves from ebay / China. Can anyone recommend a good size / size range for sifting coffee from a large conic? Will be using a V60 + paper filters for the brew process.

T.


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## MWJB (Feb 28, 2012)

If you're just going to buy two: 600 & 1180um (or nearest)

For 4 sieves: 425, 600, 850, 1180.

Use ~1 gram of grounds for every square inch of mesh.


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## dsc (Jun 7, 2013)

Cheers Mark, but are we talking sifting for grind analysis or just plain sifting to reduce the amount of finer material? I'm after the latter at this point, just not sure how fine the fines are 

T.


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## MWJB (Feb 28, 2012)

dsc said:


> Cheers Mark, but are we talking sifting for grind analysis or just plain sifting to reduce the amount of finer material? I'm after the latter at this point, just not sure how fine the fines are
> 
> 
> 
> ...


 Why do you want to reduce the fines? Why do you think this approach will give any benefit?

If you do want to know what fines are you'll need to do some preliminary analysis to determine their relationship to the rest of the distribution. Otherwise, you may as well pick an arbitrary smaller sieve, or two (maybe in the 125-177 range?), and see what you can remove without agglomeration, clogging the sieve & completely screwing up your pour regime (which won't then translate to any non-sifted brew).

If you want to reduce particles under a certain size, to clean up brews, why not grind coarser &/or sift out the largest 15-25%. It'll be much faster.

Either way, sifting every brew will be a major faff.

Even if the fines are everything below the smallest 2.5% by mass, and they all extract to the highest degree in that brew, they still likely only account for a tiny proportion of the extracted mass - maybe only 0.3g of a 10g dose, *if* extraction penetration is linear & experiments have shown that it is not necessarily so.

I don't understand the fascination with sifting fines for drip brewing, it would be like having a zoo with nothing but toenail clippings, then we imagine what the rest of the animal looked like  Why not look at the extreme particles at both end of the distribution?


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## dsc (Jun 7, 2013)

I've done very limited testing with an off the shelf kitchen strainer and had much better brews that way (taste wise that is). Actually your idea of sifting the largest 15-25% is indeed much easier so I might try that. This is purely for experiments as I can't see myself sifting every single brew.

T.


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## dsc (Jun 7, 2013)

Coming back to this as I've seen some fairly priced Endecotts sieves on ebay:

https://www.ebay.co.uk/itm/Endecotts-Sieve-100mm-Diameter-250-Micron-mesh-BNIB-B/133317168732?hash=item1f0a528e5c:g:jMgAAOSwApReJXYp

So was thinking to get smth close to say 250um and maybe 1000-1100um, with the idea being to get rid of really fine and really large particles and use the middle bit. Mad? Good? Stupid? Just not sure if 250/1000 is a good combo.

T.


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## MWJB (Feb 28, 2012)

dsc said:


> Coming back to this as I've seen some fairly priced Endecotts sieves on ebay:
> 
> https://www.ebay.co.uk/itm/Endecotts-Sieve-100mm-Diameter-250-Micron-mesh-BNIB-B/133317168732?hash=item1f0a528e5c:g:jMgAAOSwApReJXYp
> 
> ...


 It would be pretty odd to take out both really fine & really coarse from the same grind, or to remove them for the same brew method.

Let's say your average grind size is 500um (don't know what you would use this for, other than coarser cupping, maybe Aeropress), 250um would remove just a couple % mass of the finest end, 1000um the same from the coarsest end. So, you lose say 3-7% of the grind from the tails of the distribution, it can't have much impact on the extraction, it'll just screw up flow rate for drip. Once you have the brew dialled back in, I can't see the impact being significant. Go coarser and you lose less from the smallest end

For French press I sometimes take out <500 (roughly, it's just a sized chef's sieve not ISO/ASTM) and that works OK, bigger might even be better.

250-1000 is about a 4x st.dev span (unless you're using a Porlex/Hario/blade grinder), so little impact from excluded grind, almost no useful info for calibration.

100mm is only 12 sq. inches, so I wouldn't put much more that 12g in there, OK for calibration, or 1 cup brews. Not much use for sifting grounds for significantly bigger brews.

Adding a 500um in there would make the 250um & the 1000um more useful?


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## dsc (Jun 7, 2013)

Well another idea was just a single large size and grinding coarser overall, then gathering what stops on the sieve and regrinding it / binning. Just not sure what size would be good for a V60 as this is my main method.

T.


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## MWJB (Feb 28, 2012)

dsc said:


> Well another idea was just a single large size and grinding coarser overall, then gathering what stops on the sieve and regrinding it / binning. Just not sure what size would be good for a V60 as this is my main method.
> 
> T.


 1180um captures 4% to 18% depending on how coarse I grind for V60. So that, or 1000um would seem to be good candidates.


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