The probe method was used to measure thermal conductivity of beef through a temperature range of 3O-120°C. Thermal conduetivity of beef increases with temperature up to 70°C followed by a decrease during the denaturation of proteins and subsequent loss of water. The thermal conductivity of beef again increases with temperature after protein denaturation. The thermal conductivity of cooked beef is lower than raw beef up to about 80°C. The rate of increase for cooked meat thermal conductivity is fairly constant with temperature at a given moisture content. Models based on composition and temperature were found to predict the thermal conductivity of meat during cooking at an average standard percent error of 7%.

A mixed computational strategy was used to simulate and optimize the thermal processing of Haleem, an ancient eastern food, in semi-rigid aluminum containers. Average temperature values of the experiments showed no significant difference (α = 0.05) in contrast to the predicted temperatures at the same positions. According to the model, the slowest heating zone was located in geometrical center of the container. The container geometrical center F0 was estimated to be 23.8 min. A 19 min processing time interval decrease in holding time of the treatment was estimated to optimize the heating operation since the preferred F0 of some starch or meat based fluid foods is about 4.8-7.5 min.

An improved line heat source thermal conductivity probe was made to simplify the construction and extend the life of thermal conductivity probes. The accuracy of thermal conductivity measurement is also improved. The better linearity of temperature versus logarithm of time was obtained as compared to published techniques. The probe made with the heater wire and thermocouple on the outside of a sewing needle instead of inside of a hypodermic needle was checked by measuring the thermal conductivity of known samples. Results obtained with the improved probe show lower temperature rise and lower standard deviation.

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