Your analysis is only as good as the sample sent to the lab. Do your best to sample 12-15 undamaged potatoes that are representative of the bin or field. Use ventilated bags when submitting samples to ensure the samples don't sweat. When labling the samples, use a meaningful identification; labeling the samples as 1,2,3 today may not make sense a month later.
What to Test:
Test sucrose and glucose in the tubers to monitor the stability and maturity of the bin or field.