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.
- The temperature controller settings were modified. This can produce improper heating.
- Improper weighing technique. See weighing technique in the Operator's 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. The ANKOM Desiccant/Moisture Stop Assembly (X45) should be used.
Low Values:
- Grind is too fine.
- Bag is not completely sealed.
- Broken seam in bag is 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 DELTA Operator's Manual section titled Periodic Maintenance. Follow steps to the check agitation system.
- Solution is not heated sufficiently. Perform ANKOM Boil Test (see DELTA Service Procedure 13).
- For NDF, failure to use Alpha Amylase and/or Sodium Sulfite.
- For ADF/NDF, failture to pre-treat samples with high fat content (>5%) 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. Desiccant pouch should be dried regularly to refresh desiccant. Follow directions on label.
- Rinse water not hot enough or not long enough. Water should be 70°C for NDF and ADF and 50°C for CF. Rinse should run 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.