Identification of Components in the Stale Flavor Fraction of Sterilized Concentrated Milk

SUMMARY The more volatile components of the stale flavor fraction of sterilized concentrated milk (SCM) were studied by a nitrogen‐purge on‐column trapping technique. Higher‐boiling components were isolated by solvent extraction of the fat from lyophilized SCM, followed by low‐pressure reduced‐temperature steam distillation of the extracted fat. Components in the resulting flavor extract were identified by gas chromatography and mass spectrometry. The following compounds were identified in the extract from stale SCM: 2‐heptanone, 2‐nonanone, 2‐tridecanone, benzaldehyde, acetophenone, naphthalene, a dichlorobenzene, δ decalactone, benzothiazole and o ‐aminoacetophenone. Of these compounds, only the dichlorobenzene and 2‐heptanone were identified in the extract from the control SCM.