Detection method optimization, content analysis and stability exploration of natamycin in wine.

Area of Science:

• Food Chemistry
• Analytical Chemistry

Background:

• Natamycin is a fungicide used in food preservation.
• Accurate detection methods are crucial for quality control.
• Natamycin stability in wine is a significant concern.

Purpose of the Study:

• To develop and validate a novel, rapid, and sensitive method for natamycin detection in wine using High-Performance Liquid Chromatography-tandem Mass Spectrometry (HPLC-MS/MS).
• To investigate the presence of natamycin in commercial Chinese wines.
• To evaluate factors affecting natamycin stability during wine processing and storage.

Main Methods:

• Development of an HPLC-MS/MS method utilizing an Agilent 6460 instrument and an Agilent RP18 column.
• Sample preparation involved solid-phase extraction.
• Method validation included determination of limit of detection (LOD), limit of quantitation (LOQ), recovery, and relative standard deviation (RSD).

Main Results:

• The developed HPLC-MS/MS method demonstrated high sensitivity (LOD: 1μg/L, LOQ: 3.34μg/L), good recovery (70-94%), and precision (RSD: 2-4%) with a short run time of 5 minutes.
• Natamycin was not detected in any analyzed commercial wine samples from the Chinese market.
• Natamycin proved unstable in wine, with significant degradation observed due to malolactic fermentation, clarification (especially with bentonite), and light exposure during storage.

Conclusions:

• The validated HPLC-MS/MS method provides a reliable tool for natamycin analysis in wine.
• The absence of natamycin in commercial wines suggests potential degradation during production or storage, highlighting its instability.
• Bentonite clarification and light exposure are key factors contributing to natamycin degradation in wine.