Effect of NaCl on the lipid peroxidation-derived aldehyde, 4-hydroxy-2-nonenal, formation in boiled pork.

Pork was boiled at 100 degrees C for 5, 10 and 15 min and stored at 0 degrees C, and changes in the 4-hydroxynonenal (HNE), malonaldehyde (MA) and fatty acid (FA) contents were analyzed immediately and 3 days later. The HNE, MA and FA contents in all samples were not significantly different from each other. Pork samples containing none (control), 1% and 2% NaCl were boiled at 100 degrees C for 5 min and stored at 0 degrees C, and changes in the HNE, MA and FA contents and cooking yields were immediately analyzed and after 0, 1, 2 and 3 days. Cooking losses in the NaCl-containing samples were significantly lower than those of the control. The HNE contents in the control samples of boiled pork had significantly increased after 3 days of storage, while the contents in the NaCl-containing samples were significantly lower than those of the control after 1, 2 and 3 days of storage. The MA contents in all samples were not significantly different from each other. All FA contents analyzed had decreased in all samples after 3 days of storage. The decrease ratio of highly unsaturated fatty acids was lowest in the sample containing 2% NaCl.