Factors Important in Determining the Heat Process Value, F_T, for Low-Acid Canned Foods ¹

In this monograph an attempt is made to put into perspective several factors that impinge on the heat process value, F_T. In the heat processing of low-acid canned foods (LACF), there are three specific types of final product spoilage that concern the food microbiologist and the food manufacturer. These three areas are discussed in some detail. The order to follow in the design of LACF and endpoint values are suggested. Use of descriptive and numerical terms for the endpoint of the LACF heat preservation process is discussed. The origin of the term, "commercial sterility," is reviewed; reasons for replacing this term (in the future) with a specification are presented. The several faces of the widely-used heat process value, F_T, are examined. The use of a safety factor to take care of unknown processing conditions is proposed. Suggested safety factors are listed. The classical research of Esty and Meyer on resistance of Clostridium botulinum is reviewed and interpreted using the simple logarithmic model. The often-quoted but poorly-understood term, 12D, is discussed.