Bacterial inactivation mechanism of SC-CD and TEO combinations in watermelon and melon juices

Inactivation mechanism of supercritical carbon dioxide (SC-CD) combination with Thymbra spicata essential oil (TEO) treatments on bacteria in tryptone soy broth (TSB) and juices was investigated. Salmonella Typhimurium significantly inactivated by 3.45 5.55 logs after SC-CD+TEO treatment TBS for 35 min at 7.6 10.13 MPa respectively. Klebsiella pneumoniae showed higher resistance to than other two Escherichia coli S. Typhimurium. Approximately 5.27, 4.68 3.82 inactivation Typhimurium, E. K. were obtained the watermelon juice min, while 6.89, 4.82 4.55 inactivated, respectively, observed melon juice. Research indicated that involves inducing cell damage, increasing membrane permeability, rupture, precipitation cytoplasmic contents, extracting cellular substances lysing cells. Different sensitivities Gram-negative may be attributed differences structure, compositions presence capsule, pressure level exposure time. pH, total soluble solid browning degree did not change during 7 days storage.