Hi All,

Do people make a habit of sorting green beans to a specific size before roasting for better results?

If yes, are there any economical sieves anyone would recommend? I saw the Kruve bean sieves, they seem like not a bad option for the price but I couldn't find any reviews.

I skimmed the iso 4150 standard. https://cdn.standards.iteh.ai/samples/4 ... 0-2011.pdf

Are there any other specific techniques that one should use?

The cheaper sieves don't seem to have any oblong peabody sieves, is this an issue? What else might these consumer options be "missing" when compared to the more professional/commercial offerings?

Thanks for any insight you can provide!

I don't sieve but totally understand how important it might be if you notice variations in bean size. I buy through Sweet Maria's, Captain's Coffee, and Bodhi Leaf, which is at a price premium to other greens providers. True or not, my hope is that part of this premium allows their validation on greens quality, including things like bean size uniformity.

The Colino screens are relatively inexpensive https://my-tonino.com/shop/en/colino-kit

They have the slotted screens for peaberries as an option.

I have no experience with Colino. I have a set of the usual 12"x12" screens that I bought used. Based on my experience with those, the smaller Colino screens would be large enough for grading (300g).

As for sorting for roasting, I do it with some coffee because I have the screens and Tim Wendelboe said a few years ago that he bought greens by size where practical. However, I can't say that the practice is giving "better results." With no screening, the smaller beans in a batch will be roasted darker and larger beans will be roasted lighter - so a mélange roast effect, which can be beneficial, e.g., by adding "complexity." However, I will usually
screen decaf - I have found that the decafs that I have gotten had more broken bean bits, and I don't like charred bits in my coffee

Thanks Craig, Mike. Very helpful information.

The Colino kit does look impressive and good value. Presumably the Colino advantage over the kruve kit is capacity, but also work flow? With the kruve kit it seems like you can only have two screens installed at once. Then you'll have to replace and repeat?

How many sieves should one typically need to use at a time? With the Colino kit it seems like you can select up to four at a time?

You can get extra screens and extra sides for the Colina, but there is a limit to how many trays that you will want to be holding and shaking

I have 13, 15, 17, 19, and a bottom pan. So:
- the bottom pan has beans ≤ 13/64"
- the 13 pan has beans > 13/64" and ≤ 15/64"
- the 15 pan has > 15/64" and ≤ 17/64"
- the 17 pan has > 17/64" and ≤ 19/64"
- the 19 pan has beans > 19/64"

I guess that I didn't make this clear in my previous post, but I wouldn't recommend screens for a home roaster. If you're planning on going into the roasting business and buying bags of greens then it is good to screen and grade the pre-purchase samples. Otherwise, I'd equate screens to sifter screens for coffee. A bunch of folks bought the Kruve sieves for sifting coffee grounds when they came out, and people did stuff with them, but I bet that there are a lot of Kruve sifters sitting in the "drawer of old coffee stuff that never gets used anymore."

YMMV.

Fair enough! Great points, thanks again.

I definitely saw that poll about the kruve grind sieves and how most peoples are collecting dust. As an aside, maybe I should post a wtb ad for one on the cheap and then pick up the bean sieves. Anyways, you think over time the bean sieves would be as infrequently used as the grind sieves?

Apologies if I'm beating a dead horse. I'm asking again because I find that I do get significant variations in colouring between beans when I roast.

Also, I just bought some Kona greens. The farm I bought direct from had 3 levels of greens.
1) regular
2) fancy (112.5% cost of regular)
3) specialty (125% cost of regular)

They told me the only difference between them all was the grading/sizing. Other than that they were the exact same bean.

So they're not the exact same bean. The beans that passed grading/sizing are going into the more expensive levels, which means that the ones that didn't pass grading and/or are smaller sizes are in regular. Hawaii has a standard grading system for Kona - "fancy" is a recognized grade, one below "extra fancy." "Specialty" isn't a recognized grade, but if that means the greens meet SCA specialty defect standards, then I'd be buying the specialty for sure - I don't like defects in my coffee. There will always be some defects, but good grading minimizes them.

As for colour variation, I'm not sure what you mean, but quakers and semi-quakers are defects.

I'd say to get yourself a piece of cardboard or wood, spray paint it black, and learn how to grade green coffee, and do that with every green that you buy. It isn't hard or time-consuming to do, and the old versions of the guides that Trish talks about in the video are freely available as pdf's with a bit of searching. Once you're comfortable grading, then maybe consider screens?

Thank you again for sharing such incredible knowledge. I'm indebted to you!

Interesting! I have the RoastVision for colour readings - it seems to prefer a very fine grind; I use a Turkish hand grinder for preparing samples. However, it is different from a Tonino or other colorimeters as it only uses a few beans' worth of grinds for a sample.