There appears to be some concern that the sampling method (i.e. vacuum probe) grain traders use to test the admix in beans is...a tad inaccurate at times  - see link below:

http://www.fwi.co.uk/Articles/2007/10/03/107207/doubts-raised-over-accuracy-of-bean-sampling-methods.html

From what I've heard, it seems there is something in this - surely a vacuum system will suck in more lighter material than heavier bean seeds - also, smaller rubbish can probably move between beans in a lorry much easier than in something like wheat. Can a sampling system that's used for cereals really be as effective for beans when the crops are physically so different??

The chap I spoke to thought there'd be plenty of other farmers who'd experienced similar problems, so interested to hear if anyone has - either with beans, peas, cereals, etc...

Paul (FW arable)

the whole question of sampling be it grain, oilseeds or pulses is fraught.

Although HGCA did a small piece of work on sampling of grain, there appears to be a need for much more work on this basic subject.    It is a matter that has not only concerned me in the past but continues to be one that ferments much anger in this household when results come back from the final buyer - when the loaded out sample yields a different result.     It may sound relatively simple to sample a representative sample from each load, however technically it is the most difficult thing imaginable. viz:-

to sample at loading - HOW?   some load with augers, some under tanks, some with fore-end loaders.  Whatever simple system is evolved the same reading must be obtained from each method.

 To sample at tipping - too late as the mills want to know which bin to place their comodity in order to get the best blend.

 Have a rejected load and try getting back your sample for testing in another laboratory ?????? Well let me know when you win that one!

 This very simple problem still requires a lot more work and until it is done there will be little faith on either side of the great divide of producer and purchasor.     It is political, economic and a very human problem that we have - but who will make the first steps to try to sort it out?

dragon.

Always used to think that the longer peas went on a lorry, the more small bits of soil and admix settled to the bottom to be sucked up by the sampling spear. But then that was just another part in the 'dry pea cartel ripofff' that makes growing them so unattractive.

Seems that your system is fraught with troubles. Here we pay farmers on machine dressed weights, works alot better. More emphasis on the farmer to present a good sample & the dressing shed to do a good cleaning job.