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Stews were prepared by 2 processes and 4 treatments, and stored for 3 different storage periods. The two processes were beef cooked in a stew and stored in a polyethylene container at 5 ℃ (P1) and in a barrier bag at 0℃ P2). The four treatments were beef cooked alone (T1), with onions (T2), with carrots (T3) and with onions and carrots (T4). Stews in Pl were stored for 0, 2 and 4 days and stews in P2 were stored for 0, 2 and 4 weeks. Cooking decreased the cephalin content by 39%, the lecithin content by 21% and most of the phospholipid fatty acid concentrations as well as the fatty aldehyde levels in the phospholipids of beef from stew. Process or storage did not significantly affect the level of either phospholipids, however cooking beef with carrots seemed to exhibit some protection against hydrolysis of cephalin. P1 stews had a higher TBA-value (p$lt;0.05) than P2 stews, and the TBA-value of P1 stews increased linearly during 4 days storage. The TBA-value was not affected (p$lt;0.05) by treatment for any of the stews and did not change significantly during 4 weeks storage in P2 stews.
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