Inactivation of Salmonella Typhimurium, Escherichia coli O157:H7, Staphylococcus aureus, and Listeria monocytogenes in cardamom using 150 KeV low-energy X-ray

Abstract

This study aimed to investigate the inactivation effect of 150 KeV low-energy X-ray on Salmonella Typhimurium, Escherichia coli O157:H7, Staphylococcus aureus, and Listeria monocytogenes that were inoculated in dry cardamom. The D10 value for E. coli O157:H7 was 71.43 Gy and the tR values for S. Typhimurium, L. monocytogenes, and S. aureus were 53.57, 87.74, and 114.64 Gy, respectively. The irradiation did not significantly affect the amount of mono-unsaturated fatty acids (MUFAs) in cardamom; however, the content of poly-unsaturated fatty acids (PUFAs) decreased by approximate 20%. No 2-alkylcyclobutanones (2-ACBs), dimethyl disulfide and 3-methyl-thiophene were detected in the irradiated dry cardamom. These findings indicated that 150 KeV low-energy X-ray could be applied to effectively inactivate pathogens in dry cardamom. Industrial relevanceIt was shown that low-energy X-ray irradiation up to 350 Gy did not generate 2-ACBs, dimethyl disulfide and 3-methyl-thiophene in dry cardamom, which are among the major concerns with the application of food irradiation. The outcomes of this research highlight the potential of low-energy X-ray for the preservation of low moisture foods.