I am guessing "Microbiology" is the best folder to place this question in.
We are recently running into higher than normal DON levels in the wheat we are taking in from a particular geographical area in North America and as such we are keeping a close eye on our DON testing.
We had a customer complaint about a load of bran that we sent to them that was higher than FDA guidelines. During heightened testing actions resulting from that I saw something, I'm not sure what maybe it was quality intuition, that made me look at the repeatability of the equipment we are using. All of our mills are using the same equipment and testing method, and it seems fine with flour, but not so much on bran.
What equipment are other people using for DON testing and what is your standard deviation/level of repeatability that you have seen in your places of business?
Having to put out a product that is less than 1.0 or 2.0 DON I don't see a .5 swing as acceptable or a standard deviation of .3 acceptable... however if that turns out to be business standard then there is nothing I can do on my end to take care of it.
The following test data came from one large batch made in proportion and split into 10 samples each run twice:
1st Run 2nd Run Difference Sample 1 0.72 1.27 0.55 Sample 2 0.94 0.93 0.01 Sample 3 0.7 0.72 0.02 Sample 4 1.17 0.98 0.19 Sample 5 1.05 0.74 0.31 Sample 6 0.91 1.21 0.3 Sample 7 1.08 1.16 0.08 Sample 8 1.25 2.02 0.77 Sample 9 1.2 1.73 0.53 Sample 10 1.05 1.01 0.04
Average of all tests: 1.092 Median of all tests: 1.05 Standard Deviation: 0.326135
The tester we have is
ELx808 by BioTek. We received some test samples, not blind, from the manufacturer that were wheat and corn (not the product I'm having issues with) and we had excellent results. This tells me that the equipment isn't having a direct testing issue however it doesn't tell me anything with bran. The equipment isn't certified by AACC for wheat products (bran, flour, germ) just wheat itself.
We have sent samples to a sister lab to see what results they get on the bran and I thought my lab tech had sent a sample out to an outside lab but apparently that didn't happen.
Any information would be helpful.