2.4. Determination of fatty acid methyl esters
The fatty acid composition was determined according to the
official method EEC (2568/91) Annex Xa Annex Xb, modified by Rec
EEC n. 796/2002 method for the measurement of the characteristics of
olive oil and olive-residue oil as described below: approximately 0.1 g
of the chocolate fat was weighed in a 5mL screw-top test tube. To this,
2mL of heptane was added, and the contents were shaken. Then
0.2mL of 2 N methanolic potassium hydroxide solution was added,
the cap fitted with a PTFE joint was tightened and contents were
shaken vigorously for 30 s. Then the screw-top test tube was left to
separate into phases until the supernatant phase became clear. The
supernatant phase containing the methyl esters was then decanted
and gas chromatographic analysis was initiated.