Ankom XT10, Operator'S Manual

Operator’s

Manual

pg.

20

Rev

E

4/2/12

Appendix

A

–

AOCS

Official

Fat

Extraction

Procedure

ANKOM

Technology

Method

–

Version

1/30/09

AOCS

Official

Procedure

Am

5

‐

04

Rapid

Determination

of

Oil/Fat

Utilizing

High

Temperature

Solvent

Extraction

Definition

This method determines crude fat by extracting with petroleum ether. The compounds extracted are predominantly triacylglycerides.  Small 
amounts of other lipids along with minor compounds having some solubility in petroleum ether are also extracted.

Scope

This method is applicable to solid processed foods with 0-100% fat content. 

Apparatus

1.

Analytical Balance—capable of weighing 0.1 mg.

2.

Oven—capable of maintaining a temperature of 102 ± 2°C 
(ANKOM

RD

 Dryer, ANKOM Technology).

3.

Extraction instrument—capable of extracting at 90 ± 2°C.  
(XT10, XT15, XT20, ANKOM Technology).

4.

Filter Bags—constructed from chemically inert and heat 
resistant filter media, capable of being heat sealed closed and 
able to retain 1 micron particles while permitting solution 
penetration (XT4, ANKOM Technology).

5.

Heat sealer—sufficient for sealing the filter bags closed to 
ensure complete closure (1915, ANKOM Technology). 

6.

Desiccant Pouch—collapsible sealable pouch with desiccant 
inside that enables the removal of air from around the filter bags 
(

MoistureStop

 weigh pouch, ANKOM Technology).

7.

Marking pen—Solvent and acid resistant (F08, ANKOM 
Technology).

Reagents

1.

Petroleum Ether (B.P. 35-65º C).  Depending on the method 
used, other solvents such as hexanes and ethyl ether may be 
used. CAUTION: Most fat solvents are extremely flammable. 
Avoid static electricity and follow safe laboratory practices 
according to your local regulations when handling solvents. 

Precision

Results from the collaborative study (see Table 1) indicate the 
precision (S

r

, RSD

r

, r) that the analyst should use as a benchmark for 

evaluation replication in the same laboratory. 

Procedure

(see

the

Fat

Extraction

Process

section

of

the

Operator’s

Manual

for

more

detail)

1.

Place a labeled filter bag on the balance and zero the balance. 

2.

Weigh 1.5 – 2g of sample into the bag and record the weight 
(W

1

). 

3.

Heat seal the filter bag closed within 4mm of the top to 
encapsulate the sample. 

4.

It is good practice to include a blank bag periodically, 
especially when changing solvents, in order to measure any 
effect on the filter bag. 

5.

If a meat sample has an expected fat value of > 15% or a plant 
sample has an expected fat value of > 20%, then place the 
filter bag with sample in a tared weigh tin (W

4

) during the 

oven drying procedure in order to capture fat that may migrate 
out of the bag during heating. 

6.

Place samples in the drying oven for 3 hrs (see Numbered 
Note 1). 

7.

Cool the dried samples in the Desiccant Pouch, weigh and 
record the weight (W

2

). 

8.

Place filter bags with sample into the bag holder and place in 
the extractor. 

9.

Select the extraction time and proceed according to the 
extraction instruments instructions. 

10.

When the extraction process is complete place the samples in 
the oven for 15 – 30 minutes (see Numbered Note 2). 

11.

Cool in the Desiccant Pouch and weigh (W

3

). 

Calculations

Meat

samples

 ≤ 

15%

fat

and

plant

samples

 ≤ 

20%

fat

Meat

samples

>

15%

fat

and

plant

samples

>

20%

fat

%

Crude

Fat

=

100

x

(W

2

–

W

3

)

%

Crude

Fat

=

100

x

((W

2

–

W4)

 ‐ 

W

3

)

W

1

W

1

Where:

W

1

=

Original

weight

of

sample

Where:

W

4

=

Weight

of

the

weigh

tin

W

2

=

Weight

of

pre

‐

dried

sample

with

filter

bag

W

3

=

Weight

of

dry

sample

with

filter

bag

after

extraction