Résumé :
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Food enthalpies (Hs) need to be estimated accurately, as a function of temperature, in order to analyse heat transfer in food undergoing freezing or thawing Therefore, several predictive equations have been published in the literature. Since there was a need for simple-to-use equations a semitheorical equation containing three coefficients was derived using a published empirical equation for estimating frozen fraction of water in food. The three coefficients were functions of initial freezing point, moisture content, and effective specific heat of solid components. However, these coefficients were treated as empirical parameters that were estimated from Hs by an optimization method. The reliability of the equation was examined using 74% lean beef meat enthalpies. The maximum error of the estimated enthalpies was 1.10 kJ/kg which was about half of the most reliable, theoretical equation among those available in the literature.
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