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FOOD ENGINEERING – Engineering Properties of Foods - Barbosa-Cánovas G.V., Juliano P. and Peleg M.

ENGINEERING PROPERTIES OF FOODS
Barbosa-Cánovas G.V. and Juliano P.
Washington State University, USA
Peleg M.
University of Massachusetts, USA

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Keywords: Food engineering, engineering property, physical, thermal, heat, electrical,foods, density, porosity, shrinkage, particulates, powders, compressibility, flowability,
conductivity, permittivity, dielectric, color, gloss, translucency, microstructure,
microscopy, diffusivity, texture
Contents
1. Introduction
2. Thermal Properties
3. Optical Properties
4. Electrical Properties
5. Mechanical Properties
6. Properties of Food Powders
7. Role of Food Microstructure inEngineering Properties
Glossary
Bibliography
Biographical Sketches
To cite this chapter
Summary

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The engineering properties of foods are important, if not essential, in the process design
and manufacture of food products. They can be classified as thermal (specific heat,
thermal conductivity, and diffusivity), optical (color, gloss, and translucency), electrical
(conductivity andpermittivity), mechanical (structural, geometrical, and strength), and
food powder (primary and secondary) properties. Most of these properties indicate
changes in the chemical composition and structural organization of foods ranging from
the molecular to the macroscopic level. Both modern and more conventional
measurement methods allow computation of these properties, which can provideinformation about the macrostructural effects of processing conditions in fresh and
manufactured foods. Mathematical models have been fitted to data as a function of one
or several experimental parameters, such as temperature, water content, porosity, or
other food characteristics. Most engineering properties are significantly altered by the
structural differences between foods. Severalmicroscopy, scanning, and spectrometric
technologies permit close visualization of changes in structure at different levels
without intrusion. Microstructure studies have increased understanding of several
changes detected in foods resulting from treatment in emerging and conventional unit
operations, by relating these changes to engineering property characterization data and
models. In the future,structure–property modeling could lead to the synthetic
production of natural materials with improved characteristics, provided advances in
genetic engineering and biotechnology are incorporated into the food engineering field.

©Encyclopedia of Life Support Systems (EOLSS)

FOOD ENGINEERING – Engineering Properties of Foods - Barbosa-Cánovas G.V., Juliano P. and Peleg M.

1. IntroductionES
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The word engine, derived from the words engineer and engineering, comes from the
Latin word for talent, ingenium. From the onset of the Industrial Revolution to the
beginning of the twentieth century, the term was used almost exclusively to describe
power machines. Those who designed, built, and operated these machines became
known asengineers, and their profession, or expertise, as engineering. In today’s
technological world, the meaning of the term has expanded to include not only such
disciplines or activities as chemical, medical, polymer, or food engineering, but also
genetic engineering and social engineering. Although these disciplines have little to do
with engines, they heavily rely on the ingenuity from which theterm was originally
conceived.
It is difficult to define what exactly constitutes an engineering property of a certain food.
In general, however, any attribute affecting the processing or handling of a food can be
defined as an engineering property. Since many properties are related, there is usually
an arbitrary element in their classification. Traditionally, they are divided into the...