ABSTRACT
Commercial thermal processes to destroy microorganisms and/or inactivate spores are rarely, if ever, isothermal. This applies to thermal preservation of foods as well as the sterilization of pharmaceutical products. To be effective, a heat process needs to guarantee that the coldest point in the treated object has been exposed to a sufficiently high temperature for a sufficiently long time to cause the destruction of the targeted organism or spore — regardless of whether the targeted organism is actually present in the product — because the process’s aim is to guarantee the products’ microbial safety in the worst-case scenario. Also, whatever calculation method is used to assess the heat treatment’s requirements, a safety factor is almost always added and other precautions might be implemented for further security. Mandatory storage of sterilized cans in the plant before their release to the market is an example.
