Abstract:

The glycerides in lard, and the polar non-volatiles in oxidized lard prepared by controlled oxidation were analyzed
by reverse phase high performance liquid chromatography and atmosphere pressure chemical ionization mass spectrometry
(RP-HPLC-APCI-MS) after solid phase extraction (SPE). Thirty-three glycerides including seven diglycerides and twentysix
triglycerides were identified from the lard, which were dominated by 1-palmitoyl-2-linoleoyl-3-oleoyl-glycerol (16.13%),
1,3-di-oleoyl-2-linoleoyl-glycerol (15.25%) 1,3-di-oleoyl-2-palmitoyl-glycerol (12.96%), and 1-oleoyl-2,3-di-linoleoylglycerol
(8.05%), according to percentages of peak areas in the total ion chromatogram. Five diglycerides and twenty-two
mono-hydroperoxides derived from ten triglycerides were identified from the oxidized lard, where the mono-hydroperoxides
from 1-stearoyl-2-linoleoyl-3-oleoyl-glycerol (18.44%), 1-palmitoyl-2-linoleoyl-3-oleoyl-glycerol (16.03%), 1,3-di-oleoyl-
2-palmitoyl-glycerol (9.42%), 1,3-di-oleoyl-2-linoleoyl-glycerol (8.71%), trioleic (7.63%) and 1-palmitoyl-2,3-linoleoylglycerol
(7.53%) were predominant. These results showed that fat control oxidation was a mild oxidation process, since only
the oxidized products of mono-hydroperoxides of triglycerides were found from the oxidized lard.

Key words: lard, reverse phase high performance liquid chromatography, atmospheric pressure chemical ionization mass spectrometry, controlled oxidation, triglyceride, mono-hydroperoxide