Exploratory study on the effects of different storage temperatures on the volatile organic compounds of Amomi Fructus analyzed using gas chromatography–ion mobility spectrometry

Amomi Fructus is a popular functional food and culinary spice, rich in volatile organic compounds (VOCs), which are the main flavor compounds. The primary cultivation area of Amomi Fructus is in Hainan, China, where seasonal extreme high temperatures can reach approximately 38 ℃. In this study, three repeated experiments were conducted on samples stored at each temperature to ensure the reliability and repeatability of the data. This study utilized gas chromatography–ion mobility spectrometry (GC-IMS) to determine the VOCs in Amomi Fructus at different storage temperatures (-20 ℃, 0 ℃, 20 ℃, and 40 ℃) over a 90-day period. Chemometric methods, including principal component analysis (PCA), cluster analysis (CA), and partial least squares–discriminant analysis (PLS-DA), were employed to analyze differential and characteristic volatile substances. The results showed that the volatile organic compounds (VOCs) profile of Amomi Fructus was predominantly composed of terpenes, as revealed by GC-IMS analysis. At differing storage temperatures, the VOCs of the samples varied greatly. Among the samples stored at 40℃, the content of 23 compounds was relatively low compared to the other groups, while the content of 7 compounds was relatively high compared to the other three groups. Amomi Fructus stored at 0 ℃ and − 20 ℃ had relatively high VOC contents. At room temperature of 20 ℃, the content of VOCs showed little change compared with other groups, representing an effective condition for maintaining sample integrity. The main flavor compound VOCs of Amomi Fructus stored at room temperature can still be better retained with convenient and low-cost storage and transportation conditions. In conclusion, we recommend storing Amomi Fructus at 20 ℃ for industrial production, as this temperature provides the ideal equilibrium. This study provides a scientific basis for optimizing storage conditions.