Just how Important are De-Stoners?

[Breifne]

Looking to get some opinions on this question.

I know they're nice to have, but they are expensive. I've read comments from professional roasters on other forums that indicated they're "nice-to-have" items that aren't absolutely necessary. Many have indicated Indonesian coffees are the biggest culprits, as well as some other Latin American coffees that are processed naturally.

Some people have made their own contraptions that serve as de-stoners.

Other comments have basically said, "If you're getting stones in your coffees, you need to find better farms from which to buy."

Let me hear your thoughts.

 

[JohnD18]

I had asked this same question to two roasters I was with last week, they had both been roasting for nearly 10 years and said they never had any big problems. One of them did mention, as you did, that Indonesian coffees sometimes have foreign objects in them as they dry a lot of the coffee in the street over there. They said they usually catch objects in the cooling bin, but its rare that they even find anything at all.

Looking to get some opinions on this question.

I know they're nice to have, but they are expensive. I've read comments from professional roasters on other forums that indicated they're "nice-to-have" items that aren't absolutely necessary. Many have indicated Indonesian coffees are the biggest culprits, as well as some other Latin American coffees that are processed naturally.

Some people have made their own contraptions that serve as de-stoners.

Other comments have basically said, "If you're getting stones in your coffees, you need to find better farms from which to buy."

Let me hear your thoughts.

 

[topher]

Slurp is selling one. I personally have only owned one in the 20+ years I have been roasting. It sat in the corner and ended up getting cannibalized for its motor. I have never had any issues with debris in my coffee...well nothing major.

 

[ellatas]

The same question can be asked about a green coffee cleaner. The answer is that it depends.
Foreign materials are present in most green coffees. The most typical are sticks and stones but coffee can contain many surprising materials. The function of a green coffee cleaner is to remove most of the foreign materials by sifting to remove over sized and under sized materials, and by density differences. Most suppliers of green coffee that re-bag it in bags less than 60kg should 'clean' the coffee. However, even with cleaning some stones still pass through since they are the same size and density of green coffee. But once the coffee is roasted, the coffee becomes lighter and a density differential with the remaining stones becomes apparent. This allows for a simple pneumatic destoner to function.
For a small roaster that is roasting good quality coffee in small batches (less than 25kg), the risk of stones in your roasted whole bean coffee is small. It would still be advisable to visually inspect the roasted coffee for foreign materials while it is in the cooling tray and manually remove them before they leave.
For a larger roaster, the opportunity to visually see foreign materials in the cooling tray is limited and a destoner that can 'automate' the removal of stones makes more sense. Also, a pneumatic destoner also performs a lifting function that elevates the coffee so it can then feed a grinder or packaging machine.
Another point to consider with pneumatic destoners is they work best if you are adjusting the airflow to the lowest level that moves the coffee. This is likely to change with different coffee types. Too often roasters will set it and forget it at a relatively high airflow rate causing excessive bean breakage and less effective stone removal.

 

[wwcove]

Buy from a great importer of coffee and you will be fine without one.

 

[thCapn]

I visually check as I scoop green from the sack to the bucket. Nuts & bolts, bits of plastic, and a Barbie Doll head are the worst I've found in Indonesian coffees so far.

 

[Breifne]

A Barbie doll head?!?! Holy crap!! :decaf:

 

[namballe]

i get my quintals of coffee still in the shell, and after 100's of pounds of beans and doing a quick check for debris before roasting, have only found a couple of small stones. agreed, that the guys that dry on the patio or roadway are going to get more trash in with the beans. in short, if you are doing 100's of pounds a day and are worried about a stone getting hung up in your/customers machine, it may be beneficial.

 

[Breifne]

Thanks for the input on this, everyone. Basically, if you're roasting such a large quantity of coffee that a de-stoner becomes a necessity, you can probably afford one.

 

[slurp]

IMO if you are roasting high quality beans you do not need a de stoner. From what I have seen everyone using a de stoner roast crap (lower grade) coffee.

I do have one for sale that came with my new 60 Kilo.