|
Free fatty acids of two brands of domestic butter were isolated directly by a modified silicic acid column chromatography, and were analyzed by gas liquid chromatography. C_(18) FFA congeners (C_(148:0), C_(18;1), C_(18:2) and C_(18:3) were the predominant components (52.83% in brand A and 47.50% in brand B), followed by C_(16)FFA (29.39% in brand A and 30.52% in brand B) and C14FFA (11.85 in brand A and 13.76% in brand B). The other FFA were present as minor components (0.29-3.87%). Concentrations of four FFA (C₄, C_6, C_(10) and C1_(12)FFA) which would be expected to contribute strongly to hydrolytic rancidity off-flavors were below individual threshold level, except C₄FFA (56 ppm) in butter B.
|