title: Performance of a Heating Block System Designed for Studying the Heat Resistance of Bacteria in Foods.
abstract: Knowledge of bacteria's heat resistance is essential for developing effective thermal treatments. Choosing an appropriate test method is important to accurately determine bacteria's heat resistances. Although being a major factor to influence the thermo-tolerance of bacteria, the heating rate in samples cannot be controlled in water or oil bath methods due to main dependence on sample's thermal properties. A heating block system (HBS) was designed to regulate the heating rates in liquid, semi-solid and solid foods using a temperature controller. Distilled water, apple juice, mashed potato, almond powder and beef were selected to evaluate the HBS's performance by experiment and computer simulation. The results showed that the heating rates of 1, 5 and 10 °C/min with final set-point temperatures and holding times could be easily and precisely achieved in five selected food materials. A good agreement in sample central temperature profiles was obtained under various heating rates between experiment and simulation. The experimental and simulated results showed that the HBS could provide a sufficiently uniform heating environment in food samples. The effect of heating rate on bacterial thermal resistance was evaluated with the HBS. The system may hold potential applications for rapid and accurate assessments of bacteria's thermo-tolerances.
authors.affiliation: College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Xiao-Xi
authors.initials: XX
authors.lastname: Kou
authors.affiliation: College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.affiliation: College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Li-Xia
authors.initials: LX
authors.lastname: Hou
authors.affiliation: College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Huang
authors.affiliation: College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Ling
authors.affiliation: College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China.|Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164-6120, USA.
authors.forename: Shao-Jin
authors.initials: SJ
authors.lastname: Wang
mesh_terms: D001669:Biochemical Phenomena; D005516:Food Microbiology; D006358:Hot Temperature; D050296:Microbial Viability