Prediction models for the thermal conductivity of aqueous starch

• Published in: International journal of food science & technology Vol. 39; no. 7; pp. 737 - 743
• Main Authors: Hsu, C.L, Heldman, D.R
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.08.2004; Blackwell Science
• Subjects: aqueous solutions; Biological and medical sciences; corn starch; Food industries; Fundamental and applied biological sciences. Psychology; Gelatinization; granular starch; heat treatment; mathematical models; moisture; prediction; Starch and starchy product industries; starch granules; storage time; temperature; thermal conductivity; water content; Temperature; Starch; Prediction; granular starch; Thermal conductivity; Carbohydrate; Models; moisture; Gelatinization; Polysaccharide
• ISSN: 0950-5423; 1365-2621
• DOI: 10.1111/j.1365-2621.2004.00840.x

The objectives of this research were to determine the thermal conductivity of aqueous starch and to develop a theoretical model to predict the thermal conductivity for both granular and gelatinized aqueous starches. Thermal conductivity of starch was experimentally investigated as a function of moisture content (55-70%) and temperature (5-45 degrees C) by using the probe method. Six structural heat conduction models were employed to predict the thermal conductivity. Results indicated that the experimental thermal conductivity increased with increasing moisture content and temperature for both granular and gelatinized starch. The effect of gelatinization on thermal conductivity was small but significant at 5 degrees C, but insignificant at 25 and 45 degrees C. Over the moisture and temperature ranges investigated, the thermal conductivity values predicted by the Kopelman (B) and Maxwell models were in close agreement with the experimental values for granular starch, whereas for gelatinized starch, the Maxwell model yielded the lowest standard error with the experimental values.