Thermal Diffusivity Variation Study of Cold Stored Malaysian Pangasius Sutchi at 10°C

Abstract

This paper presents the use of thermal diffusivity-variation of Malaysian Pangasius Sutchi freshwater fish as a criterion to estimate the freshness in fish marketing. A homogenous specified area of a fresh fish body was cut into slices which were wrapped and preserved in a cold store of 10°C for a period of 28 days. Ansari's approach has been found earlier as an appropriate one to measure the thermal diffusivity of fish through transient cooling. The daily measurement of those slices (samples) along the muscle orientation revealed that thermal diffusivity increased up to 3 days then stayed approximately constant up to the end of the preservation period (28 days). In the literature the shelf life was also found 3 days at 10°C, which in turn agreed with the present investigation. Regression analysis was made to develop an empirical correlation between thermal diffusivity ratio and preservation time of the fish under study. This correlation could be used by food technologists as an index of deterioration of freshness or consumer acceptance