4.2
Pre-extraction
As high fat levels can prevent effective
hydrolysis, samples with 10% fat content
should be pre-extracted with the same type of
solvent as used in the final extraction.
1.Weight in the sample with a precision of
1000
±
2 mg. Load the glass thimble with 1 g
celite and the sample. Do not cover with
cotton.
2.Fit adapters on the thimbles, by
introducing them into the thimbles in such a
way that the circlip is compressed
progressively into the thimble, (i.e. the
closed side of the circlip is pressed in
first and then working towards the open
side), and insert them into the Soxtec HT
Extraction Unit.
3.Add solvent and extract for 10 minutes in
"Rinsing" position.
4.After the extraction, dry the extraction
cups in an oven at 100°C for 30 minutes. Let
them cool down and weigh them. Calculate
percentage extracted fat. If the fat
content is high, 20% , it is recommended to
use a second extraction cup for the final
extraction.
5.Remove the thimble holders from the glass
thimbles. Transfer the pre-extracted sample
as quantitatively as possible from the
glass thimble to a sample tube for acid
hydrolysis. Proceed from step 2 of the
hydrolysis part.
Note: Use the same glass thimbles for the filtration after
hydrolysis (see 4.3 position 4 )
1047
Soxtec
System
Hydrolyzing
Unit,
User
Manual,
Rev.
2.2,
Part
no
1000
3315,
Foss
Tecator
AB,
Sweden
7
1047013A
Fig. 4
Insert the tube with sample and
celite into the Hydorlyzing Unit.
