Innovative technologies for food preservation inactivation of spoilage and pathogenic microorganisms 9780128110324, 0128110325, 9780128110317

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Innovative Technologies for Food Preservation

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Innovative Technologies for Food Preservation Inactivation of Spoilage and Pathogenic Microorganisms

Edited by

Francisco J. Barba University of Valencia, Valencia, Spain

Anderson S. Sant’Ana University of Campinas (UNICAMP), Campinas, SP, Brazil

Vibeke Orlien University of Copenhagen, Frederiksberg C, Denmark

Mohamed Koubaa Ecole Supe´rieure de Chimie Organique et Mine´rale, Compie`gne, France

Academic Press is an imprint of Elsevier 125 London Wall, London EC2Y 5AS, United Kingdom 525 B Street, Suite 1800, San Diego, CA 92101-4495, United States 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, United States The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, United Kingdom Copyright r 2018 Elsevier Inc. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein). Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein. British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress ISBN: 978-0-12-811031-7 For Information on all Academic Press publications visit our website at https://www.elsevier.com/books-and-journals

Publisher: Andre Gerharc Wolff Acquisition Editor: Nina Rosa Bandeira Editorial Project Manager: Mariana Kuhl Production Project Manager: Vijayaraj Purushothaman Cover Designer: Victoria Pearson / Mohamed Koubaa Typeset by MPS Limited, Chennai, India

Contents List of Contributors

xi

Part I Introduction 1.

Conventional Technologies of Food Preservation Pedro E.D. Augusto, Beatriz M.C. Soares and Nanci Castanha 1.1 Thermal Processing 1.1.1 Thermal Processing Main Characteristics 1.1.2 Microbial Inactivation Kinetics 1.1.3 Process Design 1.2 Cooling 1.3 Freezing 1.4 Water Activity (aw) Reduction 1.5 Hurdle Technology 1.6 Conclusions References

2.

3 4 7 10 11 14 18 19 22 22

Innovative Technologies for Food Preservation Francisco J. Barba, Lilia Ahrne´, Epameinondas Xanthakis, Martin G. Landerslev and Vibeke Orlien 2.1 Introduction 2.2 Physical Technologies 2.2.1 High Hydrostatic Pressure Processing 2.2.2 High-Pressure Homogenization 2.3 Electromagnetic Technologies 2.3.1 Pulsed Electric Fields 2.3.2 Ohmic Heating 2.3.3 Microwaves 2.3.4 Radio-Frequency 2.3.5 UV-Light (Continuous and Pulsed) 2.4 Acoustic Technologies 2.4.1 Ultrasound 2.4.2 High Hydrodynamic Pressure-Shockwaves

25 26 27 31 34 34 36 36 37 39 40 40 42

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Contents

2.5 Others 2.5.1 Membrane Filtration 2.5.2 Dense Phase CO2 Acknowledgments References

3.

42 42 45 47 47

Main Groups of Microorganisms of Relevance for Food Safety and Stability: General Aspects and Overall Description Jose M. Lorenzo, Paulo E. Munekata, Ruben Dominguez, Mirian Pateiro, Jorge A. Saraiva and Daniel Franco 3.1 Introduction 3.2 Spoilage Nonspore-Forming Bacteria 3.2.1 Brochothrix spp. 3.2.2 Carnobacterium spp. 3.2.3 Lactobacillus spp. 3.2.4 Pediococcus spp. 3.2.5 Streptococcus spp. 3.2.6 Lactococcus spp. 3.2.7 Leuconostoc spp. 3.2.8 Kurthia spp. 3.2.9 Weissella spp. 3.3 Spoilage Spore-Forming Bacteria 3.3.1 Bacilli 3.3.2 Clostridia 3.4 Pathogenic Nonspore-Forming Bacteria 3.4.1 Brucella spp. 3.4.2 Campylobacter spp. 3.4.3 Salmonella spp. 3.4.4 Yersinia spp. 3.4.5 Listeria spp. 3.4.6 Escherichia coli spp. 3.5 Pathogenic Spore-Forming Bacteria 3.5.1 Bacillus spp. 3.5.2 Clostridium spp. 3.5.3 Sporulation and Germination Process and Morphology Spore 3.5.4 Contamination of Bacterial Spores to Food and Inactivation Methods 3.6 Yeasts and Molds 3.6.1 Yeast 3.6.2 Molds 3.7 Viruses and Parasites 3.7.1 Viruses 3.7.2 Parasites 3.8 Conclusion References

53 54 55 56 56 58 58 59 59 60 60 60 61 63 65 65 67 68 70 71 72 74 75 76 76 78 80 80 82 85 85 88 92 92

Contents

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Part II Microbial Inactivation After Innovative Processing of the Main Groups of Microorganism of Relevance for Food Safety and Stability 4.

Mechanisms of Microbial Inactivation by Emerging Technologies Shahin Roohinejad, Mohamed Koubaa, Anderson S. Sant’Ana and Ralf Greiner 4.1 Introduction 4.2 Inactivation Targets and Mode of Action of Emerging Technologies 4.2.1 Pulsed Electric Fields 4.2.2 Microbial Inactivation by Pulsed Electric Field 4.2.3 High Pressure Processing (HPP) 4.2.4 Ultrasounds 4.2.5 High Intensity Pulsed Light Technology 4.2.6 Microwave and Radiofrequency Electromagnetic Radiations 4.3 Conclusions Acknowledgment References

5.

111 112 112 113 116 117 120 124 125 125 126

Effects of Innovative Processing Technologies on Microbial Targets Based on Food Categories: Comparing Traditional and Emerging Technologies for Food Preservation Mehrdad Niakousari, Hadi H. Gahruie, Maryam Razmjooei, Shahin Roohinejad and Ralf Greiner 5.1 Introduction 5.2 Traditional Methods of Food Preservation 5.3 Innovative Processing Technologies of Food Preservation 5.3.1 Pulsed Electric Fields 5.3.2 High-Pressure Processing 5.3.3 Ultrasounds 5.4 Conclusions Acknowledgment References Further Reading

133 134 134 134 149 160 171 172 172 185

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Contents

6.

Designing, Modeling, and Optimizing Processes to Ensure Microbial Safety and Stability Through Emerging Technologies Hassan Masood, Francisco J. Trujillo, Kai Knoerzer and Pablo Juliano 6.1 Introduction 6.1.1 Emerging Food Processing Technologies 6.1.2 Modeling and Optimization of Emerging Technologies 6.2 Electrical Processing 6.2.1 Operational Principles and Control Parameters 6.2.2 Microbiological Modeling 6.2.3 Multiphysics Models and Numerical Simulations 6.3 High-Pressure Processing 6.3.1 Operational Principles and Control Parameters 6.3.2 Microbiological Modeling 6.3.3 Multiphysics Simulations 6.4 Ultrasound Processing 6.4.1 Operational Principles and Control Parameters 6.4.2 Microbiological Modeling 6.4.3 Multiphysics Model and Numerical Simulations 6.5 Conclusions References

187 187 188 189 190 192 195 203 205 206 208 213 213 214 215 219 220

Part III Consumer’s, Technological, Environmental and Regulatory Aspects of Application of Emerging Technologies for Food Preservation 7.

Consumer Acceptance and Marketing of Foods Processed Through Emerging Technologies Marı´a Lavilla and Elisa Gaya´n 7.1 Introduction 7.2 Global Trends of Acceptance and Trade in Foods Processed Through Emerging Technologies 7.3 Public Acceptance of Foods Processed Through Emerging Technologies 7.3.1 Brief Overview in Trends of Emerging Food Processing Technologies 7.3.2 Public Acceptance of Food Processed by High-Pressure Processing 7.3.3 Public Acceptance of Food Processed by Microwave Heating 7.3.4 Public Acceptance of Food Processed by Pulsed Electric Field 7.3.5 Public Acceptance of Food Processed by Ultraviolet Technologies

233 234 236 236 237 238 239 241

Contents

7.4 Market Development and Commercialization of Foods Processed Through Emerging Technologies 7.5 Challenges and Opportunities Acknowledgments References

8.

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244 245 247 247

Environmental Footprint of Emerging Technologies, Regulatory and Legislative Issues So´nia M. Castro, Rita S. Ina´cio, Elisabete M.C. Alexandre, Liliana G. Fidalgo, Sofia Pereira, Patrı´cia Quaresma, Paulo Freitas, Paula Teixeira, Manuela Pintado, Ana M. Gomes, Carole Tonello and Jorge A. Saraiva 8.1 Introduction 8.2 Environmental Footprint of Emerging Technologies 8.3 Current Status on International Regulations 8.3.1 United States of America 8.3.2 Canada 8.3.3 European Union 8.3.4 Japan, Australia, and New Zealand 8.4 Concluding Remarks Acknowledgments References

9.

255 256 257 258 262 264 269 272 273 273

Technological Hurdles and Research Pathways on Emerging Technologies for Food Preservation Daniela Bermudez-Aguirre 9.1 Introduction 9.2 Emerging Technologies: Technological Limitations 9.2.1 Mechanical Processes 9.2.2 Electromagnetic Technologies 9.2.3 Acoustic Technologies 9.2.4 Innovative Chemical Processing Technologies 9.2.5 Hurdle Technology 9.3 Research Needs 9.3.1 High Hydrostatic Pressure 9.3.2 Pulsed Electric Fields 9.3.3 Ohmic Heating 9.3.4 Microwave 9.3.5 Cold Plasma 9.3.6 Ultraviolet 9.4 Challenges and Opportunities 9.5 Conclusions References

Index

277 277 280 281 290 292 293 293 293 294 294 295 295 296 296 298 298 305

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List of Contributors Lilia Ahrne´ University of Copenhagen, Frederiksberg C, Denmark Elisabete M.C. Alexandre University of Aveiro, Aveiro, Portugal; Universidade Cato´lica Portuguesa, Porto, Portugal Pedro E.D. Augusto University of Sa˜o Paulo (USP), Piracicaba, SP, Brazil Francisco J. Barba University of Valencia, Valencia, Spain Daniela Bermudez-Aguirre Independent Consultant, Pullman, WA, United States Nanci Castanha University of Sa˜o Paulo (USP), Piracicaba, SP, Brazil So´nia M. Castro University of Aveiro, Aveiro, Portugal; Universidade Cato´lica Portuguesa, Porto, Portugal Ruben Dominguez Meat Technology Center of Galicia, Ourense, Sapin Liliana G. Fidalgo University of Aveiro, Aveiro, Portugal Daniel Franco Meat Technology Center of Galicia, Ourense, Sapin Paulo Freitas University of Aveiro, Aveiro, Portugal Hadi Hashemi Gahruie Shiraz University, Shiraz, Iran Elisa Gaya´n KU Leuven, Leuven, Belgium Ana M. Gomes Universidade Cato´lica Portuguesa, Porto, Portugal Ralf Greiner Max Rubner-Institut, Karlsruhe, Germany Rita S. Ina´cio University of Aveiro, Aveiro, Portugal; Universidade Cato´lica Portuguesa, Porto, Portugal Pablo Juliano CSIRO Agriculture and Food, Melbourne, VIC, Australia Kai Knoerzer CSIRO Agriculture and Food, Melbourne, VIC, Australia Mohamed Koubaa Ecole Supe´rieure de Chimie Organique et Mine´rale, Compie`gne, France Martin G. Landerslev University of Copenhagen, Frederiksberg C, Denmark Marı´a Lavilla AZTI, Derio, Spain Jose M. Lorenzo Meat Technology Center of Galicia, Ourense, Sapin Hassan Masood The University of New South Wales, Sydney, NSW, Australia Paulo E. Munekata University of Sa˜o Paulo (USP), Pirassununga, SP, Brazil Mehrdad Niakousari Shiraz University, Shiraz, Iran

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List of Contributors

Vibeke Orlien University of Copenhagen, Frederiksberg C, Denmark Mirian Pateiro Meat Technology Center of Galicia, Ourense, Sapin Sofia Pereira University of Aveiro, Aveiro, Portugal; Universidade Cato´lica Portuguesa, Porto, Portugal Manuela Pintado Universidade Cato´lica Portuguesa, Porto, Portugal Patrı´cia Quaresma University of Aveiro, Aveiro, Portugal Maryam Razmjooei Shiraz University, Shiraz, Iran Shahin Roohinejad Max Rubner-Institut, Karlsruhe, Germany; Shiraz University of Medical Sciences, Shiraz, Iran Anderson S. Sant’Ana University of Campinas (UNICAMP), Campinas, SP, Brazil Jorge A. Saraiva University of Aveiro, Aveiro, Portugal Beatriz M.C. Soares Food Technology Institute (ITAL), Campinas, SP, Brazil Paula Teixeira Universidade Cato´lica Portuguesa, Porto, Portugal Carole Tonello Hiperbaric, Burgos, Spain Francisco J. Trujillo The University of New South Wales, Sydney, NSW, Australia Epameinondas Xanthakis RISE-Research Institutes of Sweden, Gothenburg, Sweden

Part I

Introduction

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Chapter 1

Conventional Technologies of Food Preservation Pedro E.D. Augusto1, Beatriz M.C. Soares2 and Nanci Castanha1 1

University of Sa˜o Paulo (USP), Piracicaba, SP, Brazil, 2Food Technology Institute (ITAL), Campinas, SP, Brazil

1.1 THERMAL PROCESSING The thermal process is one of the most widely used methods for food preservation, even considering its drawbacks and the development of further nonthermal technologies. It is a unit operation where the food is heated to a certain temperature, maintained for a certain time in order to promote the required microbial and/or enzymatic inactivation, and then cooled. It is generally characterized by a (applied) binomial time and process temperature (t 3 T), or, even better, an equivalent time at a specific temperature (for example through the F value concept). The food preservation by thermal processing is based on the use of thermal energy (heat) for microbial and enzymatic inactivation, obtained due to protein denaturation and melting of lipid components, among other effects. However, although microbial and enzymatic inactivation is desirable, the thermal processing also results in other reactions (generally) undesirable, such as sensorial changes and nutrient destruction. The challenge, therefore, is to guarantee a safe and stable product (with the desired microbial and enzymatic inactivation), but with better sensorial and nutritional properties, with lower costs and energy saving consumption. During processing, the food is heated by a hot fluid to the process temperature, following the heat transfer mechanisms. The food is then kept at this temperature for a certain time, previously calculated in order to optimize the product characteristics (i.e., safety assurance with better sensorial and nutritional attributes), called processing time. The food is then cooled by a cold fluid, interrupting the thermal effects. The thermal processing is designed based on the process target, i.e., the most thermal-resistant undesirable microorganism or enzyme in the food

Innovative Technologies for Food Preservation. DOI: http://dx.doi.org/10.1016/B978-0-12-811031-7.00001-7 © 2018 Elsevier Inc. All rights reserved.

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product. The thermal process design will thus be calculated based on this target, ensuring safety and quality of the processed food. The thermal process target can be a vegetative cell (as in beer or milk pasteurization), a microbial spore (as in the sterilization processes of lowacid foods—such as milk, corn, and tuna), a microbial toxin (as in the pasteurization of palm heart), or an enzyme (as some resistant pectinolytic enzymes in fruit products). The process target must be chosen aiming firstly food safety, but also considering the nutritional and sensorial characteristics of the final product and the economics.

1.1.1 Thermal Processing Main Characteristics The main thermal processes used in food preservation are commonly described as commercial sterilization (usually referred as, simply, sterilization) and pasteurization. The commercial sterilization is a more drastic thermal process, where the final product should have no vegetative cells and spores capable of growing under normal conditions of transportation and storage (Codex Alimentarius, 2003). Thus, in addition to safety, it is a process that ensures stability at ambient conditions (in general for periods in the order of months to some years). It is a preserving method widely applied to low-acid foods such as milk, meat, corn, peas, carrots, and other vegetables that may be contaminated with spores of Clostridium botulinum, which represent a potential risk to the safety of the product and must be inactivated. Sterilized food is generally processed in pressurized systems, at temperatures of about 120
150 C for an appropriate time. The sterilized products show high stability and shelf life from months up to years. In this case, the final shelf life of the product is determined by physico-chemical and/or sensorial changes. Pasteurization is a milder thermal process, whose main objectives are to ensure safety and prolong food shelf life. It is a method that needs to be used with a complementary technology (such as cooling, acidification, reduction of water activity, and/or use of preservatives) to guarantee stability. It is generally carried out under atmospheric pressure, with temperatures of about 65
100 C for an appropriate time. Pasteurization is a process widely applied for the preservation of fruit juices, milks, fermented drinks, heart of palm, and other preserves, and its use implies the need for association with another preservation method. Pasteurized products have low to medium stability and variable shelf life, according to their characteristics and complementary conservation method. Their shelf life may vary from few days (as refrigerated pasteurized milk and other low-acid products with high aw) up to months or years (as juices and fruit jams and other high-acid products and/or with low aw).

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TABLE 1.1 Main Characteristics of Food Thermal Processing Inside and Outside the Packaging Processing Inside the Packaging

Processing Outside the Packaging

Solid, liquid, or particulate food

Liquid food (consistency/viscosity limitations) and, in some cases, particulates

Higher food safety

Filling process can compromise food safety

Lesser energy efficiency

Greater energy efficiency

Packaging must resist the process

Packaging must be previously sterilized

Final product with more changes and lesser homogeneity

More homogeneous final product with less physico-chemical and sensory changes

Furthermore, the thermal processing of food can be performed inside or outside the package (Table 1.1). The in-package process is conducted with the product inside the packaging, i.e., the food is packaged in a hermetic package/container and then the product-packaging system is processed. In this way, the product does not come into contact with the environment after thermal processing (i.e., after the microbial inactivation). It is important to note that in this case, the packaging used must be resistant to the process conditions (temperature and pressure) to avoid deformations that compromise it. The thermal processing inside the packaging is often called Appertization, in honor of Nicolas Appert, a French confectioner who developed methods to preserve packaged foods due to thermal processing, winning a prize in 1810 stipulated by Napoleon Bonaparte for the development of a more efficient conservation method. In the in-package thermal processes, a heating fluid is normally used and the heat is transferred to the packaging, then through the packaging, then from the packaging to the product, and finally across the product. After heating the product, it is maintained at the process temperature for a specified time and then being cooled. As the heat transfer is not instantaneous, each portion of food will have a different thermal history (T 5 f(t)) throughout the process. In this case, the process must be dimensioned for the region that the process resulted in a less lethal effect called cold spot or slower heating region (Fig. 1.1). In solid foods (conductive heating), the cold spot is typically located in the geometric center region of the product (for symmetrical packaging, for example, in the center of a cylindrical package). In liquid foods (convective heating), due to the natural convection currents formed during the process, such location is more complex, depending on several factors of the package and process (for example, the uniformity of heating) and

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FIGURE 1.1 Representation of the cold spot location (black stars) during in-package food thermal processing using cylindrical cans (longitudinal section): (A) conductive food without headspace, (B) conductive food with headspace, (C) high consistency convective food, (D) low consistency convective food, (E) particulates food with high consistency fluid, and (F) particulates food with low consistency fluid.

product (mainly the rheological properties). However, it is in the lower portion of the packaging, generally between 10% and 20% of the height of a cylindrical package. In those cases, therefore, the guarantee of a safe product (process scaled to the cold spot) will result in regions with super-processed food (edges). Finally, considering that the heat transfer by conduction is less effective than by convection, many solid foods are thermal processed with a liquid portion, aiming to guarantee a faster and more uniform heating profile. Consequently the final products are more homogeneous and have lower gradient of undesirable reactions. These products are called particulate food and

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the main examples are vegetables in brine (corn, peas, pickles, heart of palm, and beans), tuna and sardine in oil or brine, and meat products added by sauces. In these cases, the liquid fraction is heated by convection, and flow through the spaces between the solid fractions results in more uniform heating of the product. However, the convection currents are slow (around some millimeters per second) and lower than the terminal velocity of the solid fraction; consequently, the fluid movement is not enough to move the solid fraction. Therefore the cold spot of the product is established for the worst case, i.e., at the geometrical center of the solid located at the region of slower fluid heating. When the thermal process is conducted outside the packaging, the product (usually in the liquid form) is processed in heat exchangers and its packaging must be previously sterilized (by physical or chemical methods). Then product and package are put together in an appropriate environment (aseptic). Although the in-packaged processes result in higher gradient of reactions (such as microbial or enzymatic reactions, loss of nutrients, and physicochemical reactions), as well as energy consumption (lower efficiency), they are safer as they are being less likely to post-process contamination. For this reason, it is still the most used method for guarantee of food safety and preservation. The ohmic and microwave heating are two emerging technologies that can enhance the food heating, increasing the final product quality. In the ohmic heating technology, the product is heated by passing an electric current through it. Due to the low electrical conductivity of food, they act as resistors in the electrical circuit formed, dissipating the energy as heat (Joule effect) and heating. In the microwave heating technology, the electric field formed by the microwave radiation stimulates the movement of polar (water) and charged (ions) molecules. The movement of these molecules dissipates mechanical energy in the form of heat (Joule effect), heating the food. These two technologies are better described in Chapter 2, Innovative Technologies for Food Preservation.

1.1.2 Microbial Inactivation Kinetics As other chemical and biochemical reactions, the microbial inactivation rate has an exponential relationship with the temperature. In most cases, especially for bacteria, the inactivation can be described by a first-order kinetics (Eq. 1.1). This kinetics shows that the microbial reduction rate at a fixed temperature (T) is a function of the microbial load (C) in the food at a determined moment. It means that the relative microbial reduction (e.g., in percentage) is always equal for same time intervals (Eq. 1.1). By developing Eq. (1.1), Eq. (1.2) is obtained, relating the microbial inactivation

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with the first-order kinetics constant at that temperature (kT) as a function of processing time (t): dc 5 2 kT C dt
 C0 ln 5 kT t C

ð1:1Þ ð1:2Þ

Traditionally, microbial inactivation is expressed by the decimal reduction time (DT) and defined as “the time required, at a fixed temperature, to reduce one logarithmic cycle inactivation (90%) of the microbial load.” This parameter has a direct relationship with the constant of microbial inactivation rate (kT), expressed by Eq. (1.3). Then, using Eqs. (1.2) and (1.3), and the logarithm in the base 10 (log10 5 log), Eq. (1.4) is obtained: 2:303 DT
 C0 t log 5 DT Cf kT 5

ð1:3Þ ð1:4Þ

Further, the DT values obtained at different temperatures decrease at each increment of temperature, following a similar trend and then being correlated by the thermal coefficient (z), which represents the “temperature difference required to promote a reduction of one logarithmic cycle (90%) in the DT values.” The z value can thus be expressed according to the following equation:
 DT2 T1 2 T2 ð1:5Þ log 5 DT1 z The concepts of DT and z can be easily understood by evaluating the curve of microbial inactivation (that correlates the microbial load as a function of the processing time (t) at a fixed temperature (T)) and the DT values variation with the temperature (T). When the curves are obtained using logarithmic scale (Fig. 1.2), the DT and z values can be clearly identified. However, in some cases, the microbial inactivation does not follow the first-order kinetics (Eqs. 1.1
1.4) and other complex models are required to describe it (Peleg, 1999, 2006). The Weibull model is the nonlinear model most used to describe the microbial inactivation (Eq. 1.6). This kinetics is defined by two parameters, b and n, both functions of the temperature (i.e., b(T) 5 bT and n(T) 5 nT).
 C0 ð1:6Þ log 5 btn C

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C0 Microbial load, C

Microbial load, C

T

T1