A high performance liquid chromatographic (HPLC) method was developed for the determination of naringin in milk and dairy products. Samples were extracted with methanol, and the analytes were separated on a C18 column using a mobile phase consisting of 0.1% acetic acid aqueous solution and acetonitrile (75:25, V/V), detected by a diode array detector at 284 nm and quantified by an external standard method. The results showed that the linearity of this method was good in the concentration range of 5–500 μg/mL with a correlation coefficient of 0.999 9. The recoveries of powdered and liquid milk power and yogurt spiked at 0.02, 0.04, and 0.08 g/100 g were 96.2%–103.2%, 96.3%–103.7%, and 99.7%–104.1%, respectively, with relative standard deviations (n = 6) of 1.12%–2.31%, 1.25%–1.85%, and 1.24%–1.66%, respectively. The reported method is simple, rapid, accurate, repeatable, and suitable for the determination of naringin in milk and dairy products.

A gas chromatographic (GC) method for the determination of 1-oleic-2-palmitic-3-linoleic-triglyceride (OPL) in milk powder was established. The samples were extracted with ether and petroleum ether, and the extract was concentrated to near dryness, re-dissolved in n-heptane, separated on a CP-TAP CB elastic quartz capillary column, detected by a hydrogen flame ionization detector, and quantified by an external standard method. The column temperature was programmed to rise. The inlet temperature was set at 330 ℃. The samples (1.0 μL) were injected using the split mode (1:10). The detector temperature was set at 360 ℃. Nitrogen was used as the carrier gas. The makeup flow rate (nitrogen) was 25 mL/min. The recovery of OPL from spiked milk powder at 1–6 g/100 g ranged from 95.2% to 101.9%, and the relative standard deviations (RSDs) for precision ranged from 1.289% to 1.998%. The limit of detection (LOD) and limit of quantitation (LOQ) of the proposed method were 0.2 and 1.0 g/100 g, respectively. This method, therefore, is simple, accurate, repeatable, and suitable for the determination of OPL in milk powder.