title: Inactivation of Geobacillus stearothermophilus spores in low-acid foods by pressure-assisted thermal processing.
abstract: BACKGROUND
  The effect of pressure-assisted thermal processing (PATP) on the inactivation of Geobacillus stearothermophilus spores was determined in deionized water, cooked ground beef, egg patty mince, whole milk and mashed potatoes at 105 °C under 500 and 700 MPa.
  
  
  RESULTS
  The numbers of G. stearothermophilus spores in deionized water and milk were reduced by more than 6 log CFU mL(-1) at 700 MPa and 105 °C, whereas those in cooked beef were reduced by 4.27 log CFU g(-1). The inactivation patterns of G. stearothermophilus spores in all food matrices followed nonlinear behavior, showing that Weibull model fitted well to the inactivation curves of G. stearothermophilus spores in low-acid foods.
  
  
  CONCLUSIONS
  The complex food matrices caused a protective effect on the inactivation of G. stearothermophilus spores during PATP. The results provide useful information in inactivation kinetics of bacterial spores for validating PATP-processed low-acid foods.
authors.affiliation: Department of Medical Biomaterials Engineering, Kangwon National University, Chuncheon, Gangwon, 200-701, Republic of Korea; Research Institute of Bioscience and Biotechnology, Kangwon National University, Chuncheon, Gangwon, 200-701, Republic of Korea.
authors.forename: Juhee
authors.initials: J
authors.lastname: Ahn
authors.forename: Hyeon-Yong
authors.initials: HY
authors.lastname: Lee
authors.forename: V M
authors.initials: VM
authors.lastname: Balasubramaniam
mesh_terms: D000818:Animals; D002417:Cattle; D004531:Eggs / Q000382:microbiology; D005511:Food Handling / Q000379:methods; D005519:Food Preservation / Q000379:methods*; D001411:Geobacillus stearothermophilus; D006358:Hot Temperature; D008460:Meat / Q000382:microbiology; D008892:Milk / Q000382:microbiology; D011312:Pressure; D011198:Solanum tuberosum / Q000382:microbiology; D013171:Spores, Bacterial / Q000502:physiology; D014871:Water Microbiology
keywords: Geobacillus stearothermophilus; Weibull model; food matrix; low-acid food; pressure-assisted thermal processing