Check to ensure the procedures sent with your instrument were followed. Some possible variables that may affect your results are:
General Problems:
- ND chemicals can come out of solution. Heat (102 - 105°C +/- 2°C ) and stir to bring back into solution.
- Someone modified the settings on temperature controller. This can produce improper heating.
- Improper weighing technique-See weighing technique in the Appendix of the manual.
- Improper or non-use of the desiccant pouch. A standard desiccator will introduce moisture in the samples as it is being opened and closed. This will cause poor precision.
Low values:
- Grind is too fine
- Bag is not completely sealed
- Broken seam in bag allowing sample to escape from bag
- Digestion run too long (ADF & Crude Fiber)
High Values:
- The movement of the Bag Suspender is less than 1/2" (1.2 cm) up and down. Refer to your A2000 Operator's Manual section titled Periodic Maintenance.
- Solution is not heated sufficiently-Perform ANKOM Boil Test (see A2000 Service Procedure 13)
- ND- Failure to use Alpha Amylase and/or Sodium Sulfite
- AD/ND-Sample too high (>5%) in fat and not pre-treated with solvent
- Crude Fiber-always presoak with petroleum ether, not acetone
- Oven temp low, wet samples introduced next to dry samples-samples are not sufficiently dried.
- Lack of or incorrect use of desiccant pouch-check for holes in pouch, packets not dried regularly-refresh desiccant
- Rinse water not hot enough (70°C ND, AD) (50°C CF) or not long enough (5 minutes)
- Digestion not run long enough
- Acetone re-used for removing water from bags post extraction
- Improper calculation of blank bag correction or using the wrong values in the formula
- Bag sealed too low
- Too much sample in the bag
- Sample not spread out in the bag
- Vessel lid was not closed tightly enough