Floirendo P. Flores, Ernesto V. Carpio, Virgilio V. Garcia, and Ponciano S. Madamba
Food Science Cluster and Agricultural and Bio-Processing Division, University of the Philippines Los Baños, College, Laguna, Philippines
Food processing requires that food be sufficiently heated to ensure safety and attain optimum flavor. Physical and thermal properties of the food, such as density, specific heat, thermal conductivity, and thermal diffusivity, are needed to determine the conditions leading to greatest acceptability of the processed product. While many studies have been made in this area, researches are still being conducted for new products and other processes currently developed. Resulting data are then used to study the mathematical relationships among the food components and determine the effect and mode of heat transfer in foods.
Figure 1. Equipment for heated probe method. (a) heater probe, (b) hypodermic thermocouple, and (c) cross section of heater probe. |
These properties are especially important for raw and processed meat products because of the significant consumer market and the pressing need for food safety. Beef is a popular meat, and the demand for cattle meat has recently been met with the production and importation of cheaper water buffalo meat, known locally as carabeef. Wet markets sell carabeef as beef while processed beef products are labeled as partly carabeef. Since the two meat sources are closely related, a study on the thermal and physical (thermophysical) properties of carabeef would then confirm the suitability of carabeef to partially or wholly replace beef.
Results indicated that density, specific heat, and thermal conductivity were similar for those of beef. However, they differ mathematically as functions of moisture content. Density is a function of both composition and volume fraction of pores that develop during drying (porosity). Specific heat varies directly as the amount of moisture content, while thermal conductivity is affected by both moisture content and fiber arrangement. With these data, along with storage tests, carabeef was proven as having similar properties as beef in spite of the difference in the amount of fat. Further, it can be then be optimally heat-processed, leading to more products advertised as such.
Figure 2. Perpendicular-fiber TC values of carabeef |
Reference:
Floirendo P. Flores, Ernesto V. Carpio, Virgilio V. Garcia and Ponciano S. Madamba, “Thermophysical Properties of Carabeef”, Philipp Agric Scientist 90 (1): 15-21 (2007).
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Mr. Floirendo Flores finished his BS Chemical Engineering and M Sc. Food Science both in the University of the Philippines, Los Banos. He has been with the Food Engineering Division of the Food Science Cluster, College of Agriculture, UPLB since 2002. He is currently wrapping up his research at Kyushu University for the UNESCO Inter-University Postgraduate Course in Biotechnology.