title: Radio-frequency heating to inactivate Salmonella Typhimurium and Escherichia coli O157:H7 on black and red pepper spice.
abstract: The efficacy of radio-frequency (RF) heating to inactivate Salmonella Typhimurium and Escherichia coli O157:H7 on black and red pepper spice was investigated. A 27.12 MHz RF heating system consisted of two parallel-plate electrodes was used, with the sample being placed between them. Black peppers (whole and ground) and red peppers (+ 16 mesh, -16 + 25 mesh, and -25 mesh) inoculated with S. Typhimurium and E. coli O157:H7 were treated with RF energy during 50s for black peppers and 40s for red peppers, and color change of samples was evaluated after treatment. RF heating for 50s resulted in 2.80 to 4.29 log CFU/g reductions of S. Typhimurium and E. coli O157:H7 in black peppers and RF heating of red peppers for 40s reduced pathogens by 3.38 log CFU/g to more than 5 log CFU/g (below the detection limit) without affecting the color quality change. The results suggest that RF heating has the potential for novel thermal process to control foodborne pathogens in spice.
authors.affiliation: Department of Food and Animal Biotechnology, Department of Agricultural Biotechnology, Center for Agricultural Biomaterials, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Sung-Youn
authors.initials: SY
authors.lastname: Kim
authors.forename: Hun-Gu
authors.initials: HG
authors.lastname: Sagong
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Sangryeol
authors.initials: S
authors.lastname: Ryu
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kang
mesh_terms: D002212:Capsicum / Q000382:microbiology*; D015169:Colony Count, Microbial; D004203:Disinfection / Q000379:methods*; D019453:Escherichia coli O157 / Q000302:isolation & purification / Q000528:radiation effects*; D005516:Food Microbiology; D006361:Heating; D029222:Piper nigrum / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000302:isolation & purification / Q000528:radiation effects*; D017365:Spices / Q000382:microbiology