Premium
High‐Pressure Destruction Kinetics of E. coli (29055) in Apple Juice
Author(s) -
Ramaswamy H.S.,
Riahi E.,
Idziak E.
Publication year - 2003
Publication title -
journal of food science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.772
H-Index - 150
eISSN - 1750-3841
pISSN - 0022-1147
DOI - 10.1111/j.1365-2621.2003.tb12323.x
Subject(s) - agar , escherichia coli , population , microbiology and biotechnology , food science , d value , biology , chemistry , bacteria , biochemistry , medicine , genetics , environmental health , gene
High‐pressure (HP) destruction of Escherichia coli (29055) in apple juice was evaluated (150 to 400 MPa; 0 to 80 min at 25 °C) based on a dual destruction behavior consisting of pressure pulse and pressure hold (first order rate) effects. Enumeration was carried out in brain‐heart infusion agar (BHIA) and violet‐red bile agar (VRBA) to differentiate between surviving cells with and without injury. A pressure pulse at 400 MPa destroyed the entire population (10 8 CFU/mL) of E. coli. During pressure‐hold, D values (decimal reduction time) of E. coli decreased with an increase in pressure, and D values from BHIA (survivors including injured cells) were higher than from VRBA (survivors excluding injured cells). Thus, an increasing number of cells were initially injured than killed with HP treatment until finally killed. Pressure dependency of D was described by z‐value model with associated z p values (pressure range to result in a decimal change in D values) of 126 and 140 MPa on BHIA and VRBA.