ANKOM 200 Series - Manual (Page 25)

Operator’s Manual
Rev C 1/14/15
pg. 25
37. Remove the samples from the oven and place them directly in a Desiccant
Pouch. Flatten the pouch to remove ambient air and zip it tight.
Do NOT use conventional countertop or cabinet desiccators for this
analysis.
38. Allow the samples to cool to room temperature. This should take about 10 - 15 minutes.
39. Remove one filter bag from the Desiccant Pouch. Flatten the pouch to remove ambient air.
To prevent moisture from settling on the filter bags, it is important to keep
ambient air out of the Desiccant Pouch while weighing the bags. This can
be done by holding the pouch flat or zipping it shut after removing filter
bags. Zipping the bags too often can reduce the life of the Desiccant Pouch.
40. Re-weigh the filter bag (W
3
) immediately.
41. Repeat steps 39 and 40 for each filter bag in the Desiccant Pouch.
42. Ash all filter bags in pre-weighed crucibles for 2 hours at 600°C ± 15°.
43. Cool the ashed crucibles in a conventional desiccator.
44. Weigh the ashed crucibles to calculate the loss of weight of organic matter (W
3
).
45. Calculate Crude Fiber according to the formula below.
% 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)