Separation from Matrix Peaks with Reproducible Results
Analysis of Limonin in Spiked Orange Juice was performed using a simple isocratic method with MS detection. Analysis at 471.2 m/z allowed for detection of only the Limonin peak without interference of the juice matrix.
When the Filtered, Unspiked Orange Juice was injected, a small peak for Limonin was also detected (data not shown). Based on the Spiked Sample, the concentration of Limonin in the orange juice was determined to be 0.5 ppm. The method can be used in the monitoring of the production of orange juice.
Peaks:
Limonin standard, 471.2 m/z [M+H]+
Spiked Orange Juice: Limonin, 471.2 m/z [M+H]+
Method Conditions
Column: Cogent Bidentate C18™, 4μm, 100Å
Catalog No.: 40018-15P-2
Dimensions: 2.1 x 150 mm
Mobile Phase:
—50% A: DI Water / 0.1% Formic Acid
—50% B: Acetonitrile / 0.1% Formic Acid
Injection vol.: 1 µL
Flow rate: 0.5mL / minute
Detection: ESI – POS – PerkinElmer, Flexar SQ 300 Mass Spectrometer
Temperature: 25˚C
Sample Preparation:
—Standard: 5 ppm of Limonin in 20% DI Water / 0.1% Formic Acid / 40% Acetonitrile / 40% Methanol. –
—Spiked Orange Juice preparation: Orange juice was spiked with 2.5 ppm Limonin, filtered, and injected.
t0: 1.1 minute
Note: Limonin is a bitter compound which may negatively affect juice quality. The compound is found in the seeds and membrane tissue of the fruit. It is very important for groves to determine the level of Limonin in juice so the correct recovery settings for the juice production can be set. The level of Limonin can change dramatically from season to season. It also depends on the fruit size. The analysis of Limonin is crucial in production of high quality non bitter fruit juices.
Attachment
No 281 Limonin in Orange Juice LCMS pdf 0.2 Mb Download File
