Food Biochemistry and Food Processing (2 edition)

BLBS102-c38 BLBS102-Simpson March 21, 2012 14:17 Trim: 276mm X 219mm Printer Name: Yet to Come

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Thermal Processing Principles

Yetenayet Bekele Tola and Hosahalli S. Ramaswamy

Introduction

Thermal Processing Basics

Introduction

Reaction Rate

Zero-Order Reaction

First-Order Reaction

Second-Order Reaction

Common Food Microorganisms

Thermal Resistance of Food Microorganisms

Kinetics of Microbial Death

Decimal Reduction Time and Thermal Death Time

Temperature Dependency of Kinetic Parameters

Concepts of Process Lethality

Thermal Process Determination Methods

General Method

Original General Method

Improved General Method

Formula Methods

Characterization of Heat Penetration Data

Heat Penetration Parameters

The Retort CUT,fhandjhVa l u e s

Stumbo’s Method

Quality Optimization

High-Temperature Short-Time and Ultra-High

Temperature Processing

Agitation Processing

Aseptic Processing

Thin Profile and Retort Pouch Processing

Novel Thermal Food Processing Technologies

Microwave and Radio Frequency Heating

Ohmic Heating

Novel Nonthermal Processing Technologies

High-Pressure Processing

Pulsed Electric Field

Retort Types for Commercial Application

Batch Retorts

Steam Heating Retort

Water Heating Retort (Immersion and Spray Modes)

Steam-Air Heating Retort

Continuous Retorts

References

Abstract:Food intended for human consumption must be produced

in safe and stable forms to ensure availability, distribution, as well

as normal growth and development. Thus, foods are processed in

various forms to achieve these desired effects. Thermal process-

ing entails the application of heat energy for food transformation

into the desired safe and stable forms. This chapter describes the

basic principles of thermal processing and surveys conventional ver-

sus novel thermal processing methods currently available for food

transformation.

INTRODUCTION

Food processing is used to transform and/or preserve raw ingre-

dients from the farm into various food forms for consumption

by human being. Food processing often takes clean, harvested

produce or edible portions and uses them to produce attractive

and marketable food products. Fresh agricultural products (plant

and animal origin), due to their high moisture content, are highly

perishable and can be kept only for a short period of time. Es-

pecially during peak harvesting seasons, due to large volume

of these products, unless and otherwise pertinent measures are

taken, the problem leads to spoilage and high economic losses.

Furthermore, food products should be available throughout the

year in market to fulfill the demand of consumers in all seasons.

To do this, we need to minimize postharvest losses and preserve

agricultural products in a safe way with no or minimum quality

loss. The major emphasis of food processing is shelf life exten-

sion by preventing undesirable changes in the wholesomeness,

nutritive value, and sensory qualities (Ramaswamy and Marcotte

2006).

Food Biochemistry and Food Processing, Second Edition. Edited by Benjamin K. Simpson, Leo M.L. Nollet, Fidel Toldr ́a, Soottawat Benjakul, Gopinadhan Paliyath and Y.H. Hui.

©C2012 John Wiley & Sons, Inc. Published 2012 by John Wiley & Sons, Inc.

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