Volatile compounds in butter oil: IV. Quantitative estimation of free fatty acids and free δ-lactones in butter oil by cold-finger molecular distillation

Abstract

Free fatty acids (FFA) and free δ-lactones in butter oil were quantitatively estimated by cold-finger molecular distillation at 35 °C followed by silicic-acid column chromatography of the cold-finger distillate and gas chromatography of the fatty acid and lactone fraction. Typical values for FFA and free δ-lactones in butter oil prepared from export standard sweet-cream salted Australian butter were in the range 0·07–0·24, 0·75–2·4, 4·5–8·6, 34–40 and 44–89 ppm for the C4,6,8,10,12 fatty acids and 0·09–0·18, 1·2–4·9 and 3·0–5·8 ppm for the C8,10,12 δ-lactones. These values are in the range of organoleptically desirable levels.