Static electricity during the weighting process:  The largest contributor to poor results is the effect of static electricity on the weighing process. Because plastic gloves can contribute to static electricity, only use anti-static gloves. To eliminate static electricity while the bag is being weighed, you MUST use the Bag Weigh Holder (TDF52) during the weighing process.

Moisture control: Moisture Stop desiccant pouches (X45) should be used to minimize the effect of moisture on the weighing process. Verify that the desiccant pouches are in good condition (no holes and the zipper is functioning) and the packets within the desiccant pouches are still working (they should be a blue color).

BLANK values: BLANK values are used in the IDF, SDF, and TDF calculations. If you're not using the BLANK values provided by ANKOM, try using them in your calculation.

Chemicals: Because the MES-TRIS buffer can degrade in performance due to bacteria growth, making this solution daily is important. Clean all containers daily and refill with fresh solutions. Make sure that each container is securely connected to the appropriate supply tube on the instrument.

Protein and Ash Determinations: Because protein and ash values are part of the IDF, SDF, and TDF calculations, verify that your protein and ash systems are working properly and providing expected results.

Protein and Ash preparation: See the procedures detailed in the TDF Operator's Manual (Protein and Ash Determination sections) for preparing the bags for protein and ash.

Drying: Bags must be dried at 105° C to constant weight (90 minutes).

Acetone rinses: See the procedure detailed in the TDF Operator's Manual (IDF/SDF Analysis section) for performing the acetone rinses.

Sample size: Using sample sizes larger than the recommended size of 0.5 (+/- 0.05g) can cause higher results.

Digestion times: For demonstration and diagnostic purposes, you can set the digestion times to non-standard values through the Touch Screen Display. Results will be inaccurate if the instrument is run using non-standard digestion times.

Technician variability: Confirm that all technicians are following the procedures detailed in the TDF Operator's Manual to avoid any variation in results associated with different operators.

pH: Typically the pH reading should be between 3.5 and 6 before correction. If the pH reading is outside of these values check the acid and buffer solutions, and check that tubing is connected to the proper containers.

Enzyme delivery: View the enzyme containers while the enzymes are being delivered. The fluid level should go down. If the enzymes are not being delivered properly, contact ANKOM at [email protected].

Temperature control: To verify that the temperature is being properly controlled, follow the procedure detailed in the TDF Operator's Manual (QC / Calibration section).

Mixing: To verify that the mixing is being properly controlled, follow the procedure detailed in the TDF Operator's Manual (QC / Calibration section).

Sample with bound fat: It is possible you have a sample which has been highly processed and has bound the fat to the extent the fat is not available to the solvent before the TDF process. In this case, after running the TDF instrument, remove the bags, place them on the rinse stand and perform the 2 standard acetone rinses. Immediately after the rinses (no air drying) remove the bags from the stand and soak the filters in fresh pet ether for 10 minutes. Place the bags back on the rinse stand and immediately perform 2 pet ether rinses (just like the acetone rinses). When the solvent has evaporated, seal the bags and dry them normally.