[Determination of bitter components in citrus juice by high performance liquid chromatography]

Bitterness in citrus juice is primarily due to the presence of both limonin and naringin, and determination of them is a standard in controlling the quality of juice. A high performance liquid chromatographic (HPLC) method was developed for the rapid determination of bitter components in citrus juice. The HPLC conditions were as follows: ODS column with acetonitrile-tetrahydrofuran-water (17.5: 17.5: 65, v/v) as mobile phase, flow rate at 1 mL/min, 207 nm as detection wavelength for limonin, and methanol-100% acetic acid-water (40:1:59, v/v) as mobile phase, flow rate at 1 mL/min, 283 nm as detection wavelength for naringin. As results showed, for limonin and naringin, the linearity was good within the ranges of 1.00 - 50.00 mg/L (r = 0.9992) and 20.00 - 160.00 mg/L (r = 0.9988) respectively, and the detection limits were 0.07 microg and 0.14 microg, then the average recoveries were 98.69% and 100.13% with relative standard deviations of 2.5% and 1.5%, respectively. The method is simple, rapid and accurate for determining limonin and naringin in juice.