THERMODYNAMICS OF MICROBIAL DESTRUCTION DURING DRYING
In general,the resulting control in microbiological growth for a dried food material is always attributed to the reduction in water activity.Besides,reducing the water activity,the drying process could contribute towards significant reduction in microbial population in the food material.Microbial destruction is a time temperature process wherein the necessary activation energy for the biochemical reactions responsible for the thermal destruction of the microorganisms must be provided by the process.The key factors determining the rate of microbial destruction include energy flow over time along with the total enthalpy of the system and the thermodynamics of heat transfer.Drying is also essentially a time-temperature process for constant relative humidity conditions involving simultaneous heat and mass transfer.In drying most of the energy supplied is used up as latent heat of vaporization for moisture removal.The portion of energy consumed as activation energy for microbial destruction becomes relatively very small compared to the latent heat of vaporization.But the thermodynamic state of the system would vary with time following different patterns depending on the method of drying.This in turn would result in varying extents of microbial destruction by different drying methods.These variations in thermodynamics were mathematically analyzed and correlated with the thermal destruction kinetics of some common food borne pathogens with the objective of quantifying the contribution of different drying methods towards microbiological destruction.
Thermodynamics microbial destruction drying techniques
Satyanarayan R.S.Dev G.S.Vijaya Raghavan
Department of Bioresource Engineering,McGill University,21111,Lakeshore Road,Ste Anne de Bellevue,QC,H9X 3V9,Canada
国际会议
The 18th International Drying Symposium Conference(第十八届国际干燥学术大会(IDS2012))
厦门
英文
1-4
2012-01-11（万方平台首次上网日期，不代表论文的发表时间）