Study on Identification of the Pressure-Resistant Bacteria Isolated from Coconut Puree and its Lethal Effect with Combined Mild Temperature and Ultrahigh Pressure

摘要

This research based on fresh coconut and the coconut puree was conducted with the ultra-high pressure (500MPa/10min). Two strains of pressure-resistant bacteria in coconut puree were screened out and identified as Leuconstoc mesenteroides subsp mesenteroides and Leuconstoc mesenteroides subsp dextranicum When comparing with constant and intermittent pressure treatments. Treatment with the intermittent pressure of 300MPa-600MPa can greatly improve the lethal effect of pressure-resistant bacteria. The fatality rate on L. mesenteroides subsp mesenteroides and L. mesenteroides subsp dextranicum were 92.6% and 89.5%. Lethality goes up significantly along with the temperature's rising. At 65°C, lethality of L.mesenteroides subsp mesenteroides and L.mesenteroides subsp dextranicum were 98.9% and 98.2%.