Page 116 - Feed Lab

Suguna Management System Ver 1.0 / SOP / FQL / P2 - 30 Page 1 of 2

30. Estimation of Unsaponifiable Matter

FBoil gently but steadily under reflux for 1 hr or until
SCOPE
completely saponified .Complete saponification is
To determine Unsapanifiable matter in vegetable oils essential.
and this applicable to testing of vegetable fats and oils.
FTransfer sample quantitatively to the 500 ml
separating funnel with 3- 4 washings of 25 ml of
APPARATUS
FSoxhelt flask - 250 ml Capacity. petroleum ether and then add 50 ml of petroleum
ether.
FLei big condenser
FInsert the stopper and shake vigorously the
FSeparating funnel - 500 ml separating funnel for at least 1 min. Then allow
settling till the charge is clearly split in two layers.
FExtraction Cylinder -Graduated with Glass stopper
Cap. 200ml FRemove the lower layer as completely as possible
in a 500 ml beaker (B-1) without including any of the
CHEMICALS
upper Portions. Transfer upper layers to 500 ml
FEthyl alcohol, 95%. beaker (B-2).
FAqueous potassium hydroxide (KOH) : 50% by FTransfer the contents of beaker (B-1) to separating
weight, prepared by dissolving 50 g of reagent funnel and repeat the extraction at least six times,
grade KOH in 50 ml of distilled water with cooling. using 50 ml portions of petroleum ether each
time and shaking vigorously with each
FPetroleum ether; AR grade
extraction.
FSodium hydroxide (NaOH) solution 0.02 N -
FAllow the contents to settle and remove lower
accurately standardized
portion to (B-1).Transfer upper layer to (B-
FPhenolphthalein indicator solution : 1.0% in 95% 2).Transfer contents of (B-2) to separating funnel.
ethyl alcohol.
FWash the combined extracts in the separating
funnel three times, using 25ml portions of 10%
PROCEDURE
ethyl alcohol in Hot distilled water, shaking
FWeigh about 5 gm ± 0.1 mg of well mixed sample in vigorously and drawing out the aqueous alcohol
to a Soxhelt flask. Add 30 ml of 95% ethyl alcohol layer after each extraction.
and 5 ml of 50% KOH solution.

Prepared by : Approved by :
104 Director - Technical