Extraction with 0.1Mpepsin+HCl solution and n-octanol
solvent were used for olives and olive oil samples to understand
how the amount of magnesium is absorbed in the
stomach and intestinal areas of the body, respectively. A
simulated gastric juice extraction procedure was previously
applied for Fe, Cu, Mn and Zn in some foodstuffs by Hocquellet
and L’Hotellier [12]. The pepsin-containing HCl
extract of olive was obtained by adding 0.32 g of pepsin
containing 25 ml of 0.1M HCl to 0.5 g of olive and shaking
it for 2 h at 37 ◦C. After filtration, the magnesium content
of the extract was determined by FAAS. The same procedure
was applied for 60–80 g of oil. A 5 min centrifugation
step at 50 Hz was added only for oil samples. Extraction
with n-octanol solvent was carried out adding 10.0 ml of
solvent into 1.0 g of olive. The organic phase was decanted,
centrifuged and diluted with ethanol (1:1 dilution). FAAS
determinations were made. Olive oil samples are completely
soluble in n-octanol. The operating conditions for
fractionation studies are summarised in Table 1