ABSTRACT
Published data on thermal conductivity of food materials are selected from the literature and organized into a database. Useful information concerning both the characteristics of the database, and statistics of the included data are presented.
INTRODUCTION
Thermal conductivity is one of the primary thermophysical properties needed in food process design and optimization. Although highly desirable, a generic model to predict the thermal conductivity of the foods does not exist (1). On the other hand the available literature data are scarce (2).
In recent review papers literature data are selected and analyzed (2) and a parallel structural model (also taking into account the temperature effect) was fitted to all literature data compiled for selected food materials (3).
The original data used in the above papers were organized into a data base and presented here. They can be used in research to validate structural models and to develop generic models to predict thermal conductivity of foods.
DATA
An exhaustive literature search was made in the most popular food engineering and food science journals during the recent years as follows (2):
Drying Technology, 1983–1999 | |||||
Journal of Food Science, 1981–1999 | |||||
International Journal for Food Science and Technology, 1988–1999 | |||||
Journal of Food Engineering, 1983–1999 | |||||
Transactions of the ASAE, 1975–1999 | |||||
International Journal of Food Properties, 1998–2000 |
DATABASE DESCRIPTION
The selected data were organized into a database developed in Excel. Every record in the database includes the following fields:
Category: The food category | |||||
Material: The material name | |||||
Species: More characteristics of the material | |||||
Thermal Conductivity: The measured value of the diffusivity | |||||
Moisture Content: The corresponding material moisture content | |||||
Temperature: The corresponding material temperature | |||||
Method: The method of measurement | |||||
Type: The presentation format of the data, e.g. values, equations, graphs | |||||
Citation: The paper from which the data are retrieved |
Database of Thermal Conductivity Data [List of Reference is Given by Krokida et al. (2).]
STATISTICS
Some statistics of the available data are summarized in Tables .
Number of Data for Each Material
Number of Data for Each Food Category
Number of Data for Each Presentation Format of the Data
Number of Data for Each Method of Experimental Measurement
CONCLUSION
Literature data of thermal conductivity of foods were organized into a data base and presented. They can be used in research to validate structural models and to develop generic models to predict thermal conductivity of foods.
Acknowledgments
REFERENCES
- Chen , X.D. , Xie , G.Z. and Rahman , M.S. 1998 . Application of the Distribution Factor Concept in Correlating Thermal Conductivity Data for Fruits and Vegetables . International Journal of Food Properties , 1 ( 1 ) : 35 – 44 .
- Krokida , M.K. , Panagiotou , N.M. , Maroulis , Z.B. and Saravacos , G.D. 2001 . Thermal Conductivity: Literature Data Compilation for Foodstuffs . International Journal of Food Properties , 4 ( 1 ) : 111 – 140 .
- Maroulis , Z.B. , Saravacos , G.D. , Krokida , M.K. and Panagiotou , N.M. 2001 . Thermal Conductivity Prediction for Foodstuffs: Effect of Moisture Content and Temperature . International Journal of Food Properties , (in press)