Catalytic Mechanism of Lipid Oxidation following High Pressure Treatment in Pork Fat and Meat

Abstract

Addition of citric acid (0.02%) inhibited the increased rate of lipid oxidation found in rendered pork fat following pressure treatment (650-800 MPa). This indicated that transition metal ions were probably released from complexes and became available to catalyze lipid oxidation in the pressure treated fat. In minced pork and washed fibers citric acid was less effective in inhibiting oxidation in pressure treated samples because of its pH lowering effects. However, the less acidic ethylenediaminetetraacetic-acid disodium salt (Na 2 EDTA) was an effective antioxidant in these pressure treated (400 MPa and 800 MPa) systems. This further indicated that metal catalysts (probably iron) were released from complexes during pressure treatment to catalyze lipid oxidation.

Effects of high pressure treatment on physicochemical characteristics of fresh oysters (Crassostrea gigas)

“…Angsupanich and Ledward (1998) reported that treatment at -400 MPa had little effect on lipid oxidation in cod muscle, but that a significant increase in oxidation was seen following treatment at higher pressures. Cheah and Ledward (1997) and Angsupanich and Ledward (1998) proposed that the major reason for the acceleration of lipid oxidation by HP treatment was an increase in free metal ion (Fe and Cu) content of minced pork and cod muscle. It is possible that the change in colour of oyster tissue and oyster adductor muscle may be linked to lipid oxidation.…”

High Pressure Processing of Meat, Meat Products and Seafood

“…Catalysis of lipid oxidation seems to take place during pressurization and has been related to the release of non-haem iron and membrane damage. Cheah and Ledward [24,25] reported that the effect of HPP on oxidative stability of lipids in pork meat depends on the applied pressure, with a value between 300 and 400 MPa constituting the critical pressure to induce catalysis. They also reported that denatured forms of proteins play an important role in catalysing lipid oxidation.…”

“…Carlez et al [23] reported that meat discolouration in pressure-processed meat was due to the following: (1) a whitening effect due to myoglobin denaturation and/or to haem displacement or release and (2) oxidation of the ferrous myoglobin to ferric myoglobin above 400 MPa. Cheah and Ledward [25] improved the colour stability with the application of pressure of 80-100 MPa for 20 min, as measured by the rate of formation of metmyoglobin in beef muscles post-slaughter. However, pressure treatment of these muscles at 7-20 days post-slaughter did not improve their colour stability.…”

Changes in Lipid Oxidation and Fatty Acids in Altay Sheep Fat during a Long Time of Low Temperature Storage

“…Some researchers have found that raw and cooked fat are very susceptible to lipid oxidation during processing and subsequent storage 5 . Due to the high content of lipid in Altay sheep tail fat, it is very easy to be affected by the outside environment and lead to corruption.…”