Chemical and instrumental analyses of warmed-over flavor in beef

A study evaluated and compared data obtained from chemical, instrumental, and sensory analyses in samples of raw, fresh-cooked, and recooked stored beef muscle. Characteristic descriptors attributed to the warmed-over beef included rancid, stale, metallic, and "cardboardy." While gas chromatographic analysis did not detect volatiles commonly associated with lipid oxidation, total volatiles and 2 specific volatiles (hexanal and 2,3-octanedione) correlated with the adverse sensory scores and with 2-thiobartituric acid values. Chromatograms and relative levels of compounds identified are included. (wz)