Estimating Food Temperatures During Various Processing or Handling Treatments

SUMMARY— A procedure was developed for predicting the transient temperature of a solid food exposed to time variable ambient temperatures. Duhamel's theorem was applied to the empirical formulas used for calculating the temperature of a food subjected to a step change in its ambient temperature. The formulas contain two constants: f, the slope index of a heating or cooling curve of a food; and j, the intercept coefficient of the heating or cooling curve. With the procedure developed transient temperature can be estimated without regard to the geometric shape of the food provided the f and j values are known. A table is presented to reduce computations involved in the procedure. Sample calculations are given for a fresh orange, a fresh carrot and a canned food product.