Ndf analysis, Important, Operator’s manual – ANKOM 2000 Series User Manual
Page 19

Operator’s Manual
Rev E 1/14/15
pg. 19
NDF Analysis
NDF Calculation
NDF contained within a food or feed sample can be calculated using the following formula:
% NDF (as-received basis)
=
100 x (W
3
– (W
1
x C
1
))
W
2
Where:
W
1
=
Bag tare weight
W
2
=
Sample weight
W
3
=
Dried weight of filter bag with fiber after extraction process
C
1
=
Blank bag correction (running average of final oven-dried weight
divided by original blank bag weight)
NDF Sample Preparation Procedure
To prepare samples for fiber analysis, follow the procedure detailed below.
IMPORTANT
When using the ANKOM
2000
Fiber Analyzer for NDF analysis, at least one blank filter bag
should be included with the sample set as an indicator of particle loss. A running average
of the blank bag weights is used in the fiber calculation as the C
1
correction factor. A C
1
value larger than 1.0000 indicates that sample particles were lost from filter bags and
deposited on the blank bag(s). Any fiber particle loss from the filter bags will generate
erroneous results. If particle loss is observed, the grinding method should be evaluated.
1. Using a Solvent Resistant Marker, number all of the filter bags you will use
during the fiber analysis.
2. Weigh and record the weight of each empty filter bag (W
1
).
3. Set the Heat Sealer dial to between 4 and 5. (The setting may vary from sealer to
sealer.)
4. Seal at least one empty filter bag (to be used as a blank)
within 4mm of its open end. Keep the sealer arm down for 2
– 3 seconds after the red sealer light turns off (to cool the
seal). The seal can be seen as a solid melted stripe along the
top edge of the filter bag (as shown to the right). If the seal
is not strong, re-seal the bag.
Seal