Investigation on the Effect of Three Different Nonthermal Sterilization Methods on Volatile Organic Compounds in Safflower Using HS-GC-IMS.

During the transportation, storage, and processing of safflower, it is susceptible to contamination by microorganisms, which may seriously affect the quality and safety of the flowers. Therefore, sterilization is an important step in ensuring the safety, quality, and stability of safflower products. In this study, headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) was utilized to compare the volatile organic compounds (VOCs) in safflower samples before and after sterilization with three nonthermal sterilization technologies (60Co irradiation sterilization, ultraviolet sterilization, and ozone sterilization). A total of 70 VOCs were detected in all of the safflower samples. According to the two-dimensional and three-dimensional difference contrast spectra and the fingerprint results of HS-GC-IMS, the VOCs in the safflower samples processed with the three nonthermal sterilization methods varied. By conducting principal component analysis (PCA), cluster analysis (CA), and partial least-squares regression analysis (PLS-DA) on the VOCs, it was found that 3-methyl-2-butenal, 2-heptanone, and 4-methyl-2-pentanone were the main contributors to the differences between the groups. HH-01 (not sterilized) differed significantly from HH-03 (UV sterilized) and HH-04(ozone sterilized) and differed the least from HH-02(60Co irradiation sterilized), suggesting that 60Co irradiation sterilized had the least effect on the VOCs of safflower. Therefore, 60Co irradiation technology is recommended to sterilize safflowers in large-scale production. This study provides a scientific basis for future large-scale sterilization processing of high-quality safflower. The results of this study demonstrate that HS-GC-IMS can provide strong technical support for the identification and authenticity assessment of VOCs in safflower samples.