Page 72 - Feed Lab

Estimation of Crude Fibre Suguna Management System Ver 1.0 / SOP / FQL / P2 - 06 Page 2 of 2

FTransfer the residue to clean dry silica crucible. Dry
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the residue at 105 C +/- 20 C in hot air oven for
minimum 4 hours. Cool and weigh. (Picture - 13)

Picture - 7 Picture - 8

REAGENTS
F0.255N (+/-0.005N) Sulphuric acid: About 7 ml
of concentrated sulphuric acid is dissolved in
Picture - 9 Picture - 10
distilled water to get one litre of solution.
F0.313N (+/-0.005N) Sodium Hydroxide: About
12.78gm of sodium hydroxide is dissolved in
distilled water to get one litre of solution.

PROCEDURE
FWeigh 2 gm of sample into a 500 ml tall form
beaker. Add 200 ml of 0.255 N sulphuric acid.
Heat gently on a hot plate and boil for exactly 30
Picture - 11 Picture - 12
minutes. (Picture - 9)
FFilter the same in a filter flat bottom flask through
muslin cloth held over funnel. Wash residue on
cloth with 200 ml to 300 ml hot water, till free from
acid. (Picture - 10)

FTransfer the material from cloth to the same beaker.
Add 200 ml of 0.313N sodium hydroxide, boil for
exactly 30 minutes. (Picture - 11)
Picture - 13 Picture - 14
FFilter through same cloth on the filter flat bottom
flask. Wash residues on cloth 200 ml to 300 ml hot FThen incinerate the dried residue in a muffle furnace
water, till free from alkali. (Picture - 12) at 600 C+/- 20 C for 30 minutes. Cool and weigh.
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(Picture - 14)
CALCULATION

(Weight of silica crucible (weight of silica crucible
With contents before ashing) - with contents after ashing)
Crude Fibre % = ----------------------------------------------------------------------------------------X 100
Sample weight, g

REFERENCE
1. Bureau of Indian Standard IS 7874 1975
2. Association of Official Analytical Chemist 2000.

Prepared by : Approved by :
60 Director - Technical