Heat transfer in solid-liquid mixtures in cans

This study, started in October 2007, was supported by TUBITAK-TOVAG (The Scientific and Technological Research Council of Turkey – Agriculture, Forestry & Veterinary Research Grant Committee) with a project number of 107O619, and completed in October 2008.

Selin Kiziltas (Masters Student) was involved in this project and financially supported by TUBITAK.

Abstract

Thermal processing is the most common technique used for preservation of foods today, and canning still provides a universal and economic method for preserving and processing foods. Conduction and natural convection inside the cans are the main heat transfer mechanisms in relation to the thermal processing of mixtures of solid-liquid foods. Actually, this is a complex problem in computational fluid dynamics (CFD) area. Literature, however, lacks in simulation studies (determination of temperature distribution and velocity profiles) of thermal processing of solid-liquid mixtures where solids are randomly dispersed in liquid phase, e.g. canned pea. Therefore, the objective of this study is to determine temperature changes inside a can containing solid-liquid food mixtures during thermal processing. For this purpose, temperature changes inside pea cans were determined using Ansys (V.11) CFD program. In the experimental studies, the cans were prepared in 500 g capacities using contents of the samples purchased from a local store, and temperature changes were measured using needle type thermocouples. Then, the project was completed with validation studies by comparing experimental and simulation results. Knowing temperature changes would lead to evaluation of sterilization value and nutritional losses effectively and use of these in optimization algorithms of the CFD programs to determine optimum processing times. This study is expected not only to be a significant contribution to the literature but also to form fundamentals of industrial projects for better improvements of canning industry.