关键词: 芒果汁, 进料温度, 均质次数, 压力, 大肠杆菌, Weibull模型

Abstract: The inactivation kinetics of Escherichia coli in mango juice by high pressure homogenization (HPH) was fitted with the Weibull model to predict the inactivation effect in this study. E. coli was subjected to HPH treatments (inlet temperature: 20–60 ℃; pressure: 40–190 MPa, and passes: 1–5). The reduction in E. coli was enhanced with increasing pressure, inlet temperature or number of passes. The reduction in E. coli in the sample after one pass at 50 ℃ was enhanced from 0.46 to 5.16 (lg(CFU/mL)) with pressure increasing from 40 to 190 MPa, which reached the hygienic requirements for non-thermally processed food claimed by the US food and drug administration. The reduction in E. coli after one pass at 70 MPa was enhanced from 0.34 to 5.02 (lg(CFU/mL)) with inlet temperature rising from 20 to 60 ℃. The reduction in E. coli at 190 MPa and 20 ℃ was enhanced from 1.73 to 5.15 (lg(CFU/mL)) with increasing number of passes from 1 to 4. The Weibull model provided a good fit to the inactivation curves of E. coli at different HPH treatments, with R2 > 0.90. The simplified Weibull models were fitted well under 20–50 ℃/40–190 MPa for one pass and 20–40 ℃/190 MPa for 1–5 passes (R2 > 0.92). The simplified Weibull models to predict HPH inactivation kinetics of E. coli could provide a theoretical basis for microbial safety control in the HPH processing of mango juice.

Key words: mango juice, inlet temperature, number of passes, pressure, Escherichia coli, Weibull model