Page 67 - Feed Lab

Estimation of Crude Protein - Kjelteck 2100 Distillation Method Suguna Management System Ver 1.0 / SOP / FQL / P2 - 04 Page 2 of 3

Preparation of 4 % Neutral Boric Acid(BA)
FTake 750 ml hot neutral distilled Water in one L
beaker. Stir well using magnetic stirrer. Add 40 gm
BA to the hot water. Stir until all crystal gets
dissolved. (Picture - 11)

FAdd 10 ml Bromocresol green solution and 7 ml of
methyl red solution to the boric acid solution and
transfer to one litre reagent stopper bottle. (Picture -
Picture-7 Picture-8
12)

FAfter cooling, make up to 1000ml and Shake well. It
should be used only after a time gap of minimum
one day from the date of preparation. (BA solution
should always be neutral) (Picture - 13)

Picture-9 Picture-10

REAGENTS
F Potassium sulphate , AR grade

FCupric sulphate penta hydrate, AR grade
Picture-12 Picture-13
FNitrogen Free concentrated sulphuric acid, AR
Grade PROCEDURE
FWeigh accurately one gram of ground sample in a
F40 % Sodium hydroxide w/v, AR grade
butter paper. Fold the paper and transfer to the
F0.2 N Hydrochloric acid - 17.46 ml/L of distilled digestion tube. (Picture -14)
water, AR grade 35.4 % assay
FWeigh 7gm of potassium sulphate and 0.8gm
F0.1 N Sodium Hydroxide 4 gm/ L of distilled water, Copper sulphate pentahydrate in another butter
AR grade paper and transfer to the same digestion tube.
(Picture -15)
F0.1 N Potassium Hydrogen Phthalate - 5.1055 g /
250 ml of distilled water, AR grade FAdd 12-15 mlof Con. H SO . Digest in the digestion
4
2
o
block for 45 minutes at 400 C. (Picture -16)
FAfter digestion is completed cool the digestion tube
in room temperature. Add 75 ml distilled water to
the same digestion tube and cool (Picture -17)

FTake 25 ml 4% Neutral Boric acid solution to a
conical flask and raise the platform so that the
distillate outlet is immersed in the receiver solution.
(Picture -18)

FPlace the digestion tube in the distillation unit and
Picture-11

Prepared by : Approved by :
55 Director - Technical