Manual

Operator’s Manual
Rev E 1/14/15 pg. 25
Crude Fiber Analysis
Crude Fiber Calculation
Crude Fiber contained within a food or feed sample can be calculated using the following formula:
% Crude Fiber
=
100 x (W
3
– (W
1
x C
1
))
W
2
Where:
W
1
=
Bag tare weight
W
2
=
Sample weight
W
3
=
Weight of Organic Matter (loss of weight on ignition of bag and fiber)
C
1
=
Ash corrected blank bag factor (running average of loss of weight on
ignition of blank bag / original blank bag)
Crude Fiber Sample Preparation Procedure
To prepare samples for fiber analysis, follow the procedure detailed below.
IMPORTANT
When using the ANKOM
2000
Fiber Analyzer for Crude Fiber 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