000 Handbook of

Food Processing Equipment 000

FOOD ENGINEERING SERIES

Series Editor

Gustavo V. Barbosa-Canovas, Washington State University

Advisory Board

Jose Miguel Aguilera, Pontifica Universidad Catolica de Chile Pedro Fito, Universidad Politecnica Richard W. Hartel, University of Wisconsin Jozef Kokini, Rutgers University Michael McCarthy, University of California at Davis Martin Okos, Purdue University Micha Peleg, University of Massachusetts Leo Pyle, University of Reading Shafiur Rahman, Hort Research M. Anandha Rao, Cornell University Yrjo Roos, University College Cork Walter L. Spiess, Bundesforschungsanstalt Jorge Welti-Chanes, Universidad de las Americas-Puebla

Food Engineering Series

Jose M. Aguilera and David W. Stanley, Microstructural Principles of Food Processing and Engineering, Second Edition (1999)

Stella M. Alzamora, Maria S. Tapia, and Aurelio Lopez-Malo, Minimally Processed Fruits and Vegetables: Fundamental Aspects and Applications (2000)

Gustavo Barbosa-Canovas and Humberto Vega-Mercado, Dehydration of Foods (1996)

Pedro Fito, Enrique Ortega-Rodriguez, and Gustavo Barbosa-Canovas, Food Engineering 2000 (1997)

p.1. Fryer, D.L. Pyle, and C.D. Rielly, Chemical Engineering for the Food Industry (1997)

Richard W. Hartel, Crystallization in Foods (2001) Marc E.G. Hendrickx and Dietrich Knorr, Ultra High Pressure Treatments of Food

(2002) S.D. Holdsworth, Thermal Processing of Packaged Foods (1997) Lothar Leistner and Grahame Gould, Hurdle Technologies: Combination Treatments

for Food Stability, Safety, and Quality (2002) Michael 1. Lewis and Neil 1. Heppell, Continuous Thermal Processing of Foods:

Pasteurization and UHT Sterilization (2000) Rosana G. Moreira, M. Elena Castell-Perez, and Maria A. Barrufet, Deep-Fat

Frying: Fundamentals and Applications (1999) Rosana G. Moreira, Automatic Control for Food Processing Systems (2001) M. Anandha Rao, Rheology of Fluid and Semisolid Foods: Principles and

Applications (1999)

000

Handbook of Food Processing Equipment

000

by

George D. Saravacos Rutgers the State University ofNew Jersey and the National Technical University

Athens, Greece

and

Athanasios E. Kostaropoulos Agricultural University of Athens

Athens, Greece

Springer Science+Business Media, LLC

000

Handbook of Food Processing Equipment

000

by

George D. Saravacos Rutgers the State University ofNew Jersey and the National Technical University

Athens, Greece

and

Athanasios E. Kostaropoulos Agricultural University of Athens

Athens, Greece

Springer Science+Business Media, LLC

664' .0028' 4--dc21

Library ofCongress Cataloging-in-Publication Data

Saravacos, George D., 1928-Handbook of food processing equipment I by George D. Saravacos and

Athanasios E. Kostaropoulos. p. cm.

Includes bibliographical references and index. ISBN 978-1-4613-5212-9 ISBN 978-1-4615-0725-3 (eBooi::)

I. Food industry and trade-Equipment and supplies. I. Kostaropoulos, A. E. H. Title.

TP373.S2372002 2002072776

ISBN 978-1-4613-5212-9

<:1 2002 Springer Science+Business Media New Vork Origina lly published by K IlI wer I Plenum Publishers, New Vork in 2002

Soficoverrcprint of the hardcover I st edit ion 2002

10 9 8 7 6 5 4 3 2 I

A C.l.P. record for this book is avai lable from the Library of Congress.

All rights reserved.

No part of this book may be reproduccd, stored in aretrieval system, or transmitted in any fonn or by any means, electronic, mechanical, photocopying, microfilming

recording, or otherwise, without written pennission from the Publisher, with the exception of any material supplied specifically for the purpose ofbeing enlered and executed on a computer

system, for exclusive use by the purchaser of the work.

DOI 10.1007/978-1-4615-0725-3

To our wives Katie Saravacos and Sandri Kostaropouios for encouraging, supporting, and enduring

Preface

Recent publications in food engineering concern mainly food process engi­neering, which is related to chemical engineering, and deals primarily with unit operations and unit processes, as applied to the wide variety of food processing operations. Relatively less attention is paid to the design and operation of food processing equipment, which is necessary to carry out all of the food processes in the food plant. Significant technical advances on processing equipment have been made by the manufacturers, as evidenced by the efficient modem food pro­cessing plants. There is a need to relate advances in process engineering to proc­ess equipment, and vice versa.

This book is an attempt to apply the established principles of transport phe­nomena and unit operations to the design, selection, and operation of food pro­cessing equipment. Since food processing equipment is still designed empiri­cally, due to the complexity of the processes and the uncertainty of food properties, description of some typical industrial units is necessary to understand the operating characteristics. Approximate values and data are used for illustra­tive purposes, since there is an understandable lack of published industrial data.

Simple diagrams are used throughout the book to illustrate the principles of construction and operation of each type of food processing equipment. Such dia­grams are very useful for introducing the readers (students, scientists, engineers, and technologists) to complex industrial equipment. Detailed illustrations and pictures of processing equipment can be found in bulletins and technical infor­mation, provided by the manufacturers and suppliers. Addresses of representa­tive suppliers of equipment are found in the directories of equipment and the international equipment exhibitions (Chapter 2), and the list of equipment sup­pliers (Appendix E). Although most suppliers listed are based in Europe or the United States, some other international suppliers are also included. Equipment companies are often consolidated or absorbed by multinational groups, and sup­pliers lists should be updated regularly.

Chapter 1 serves as an introduction to the design of food process and food plant design, based on the established chemical process design, stressing the spe­cial requirements for food quality and food safety in food processing operations.

Vll

Vlll HANDBOOK OF FOOD PROCESSING EQUIPMENT

Chapter 2 reviews the elements of mechanical and hygienic design of food pro­cessing equipment. Preliminary sizing and costing of the main processing equip­ment is discussed, and a preliminary cost estimate of a food processing plant is given. Numerical examples of sizing process equipment are given in various chapters of the book. For illustrative purposes, the equipment used in a citrus processing plant is considered in most calculations. Selection of food processing equipment can be made from typical suppliers, listed in the directories of Chapter 2, or in the supplier addresses of Appendix E.

Chapters 3 to 11 discuss the various processing equipment on the basis of unit operations of mechanical processes, heat transfer, evaporation, dehydration, re­frigeration and freezing, thermal processing, and mass transfer. Chapter 12 deals with equipment of novel food processes, such as membrane separations and supercritical extraction, and Chapter 13 covers the food packaging equipment. Appendixes at the end of the book review briefly food physical properties, food process control, and food plant utilities, and provide a list of symbols and units, conversion of technical units into the international system (SI), and a representa­tive list of equipment suppliers.

We wish to acknowledge the contributions and help of many people during the long time of collecting data and information for writing this book: our col­leagues, associates, and graduate students at Rutgers University, Cornell Uni­versity, National Technical University of Athens, and Agricultural University of Athens. The senior author is especially indebted to his former colleagues at Cornell University, D. Farkas and the late 1. Moyer, for recognizing the impor­tance of food processing equipment. We both appreciate the useful information provided by various technical and management people in the food processing industry and the suppliers of processing equipment.

We thank Z. Maroulis and N. Stoforos for reviewing Chapters 1 and 10, re­spectively, and N. Zogzas for allowing the use of his computer program of the psychrometric chart. Special thanks are due to Magda Krokida for her substan­tial help in preparing the numerical examples and a number of tables and figures of the book. We appreciate the help of N. Kostaras and Myrto and Amaryllis Kostaropoulos for preparing various figures of the book.

We hope that this book will contribute to the recognition of food processing equipment as an important part of the developing field of food engineering. We welcome the comments and criticism of readers of the book. Any errors that might be found are unintentional.

George D. Saravacos Athanasios E. Kostaropoulos

Contents

Chapter I-Design of Food Processes and Food Processing Plants...... I I. Introduction............................................ 1

II. Overview of Chemical Process and Plant Design . . . . . . . . . . . . . . . . 2 1. Process Flowsheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Types of Process Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Material and Energy Balances. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Design of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 5. Plant Layout and Buildings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6. Economic Analysis in ProcesslPlant Design. . . . . . . . . . . . . . . . . . 7

a. Fixed Capital Investment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 b. Cost of Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 c. Engineering Cost Indices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

7. Manufacturing Cost and Profitability. . . . . . . . . . . . . . . . . . . . . . . 10 a. Manufacturing Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 b. Profitability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 c. Break-Even Point. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

8. Computer-Aided ProcesslPlant Design. . . . . . . . . . . . . . . . . . . . . . 13 III. Design of Food Processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1. Unit Operations in Food Processing. . . . . . . . . . . . . , . . . . . . . . . . 15 2. Food Process Flowsheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 3. Material and Energy Balances. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 4. Computer-Aided Food Process Design. . . . . . . . . . . . . . . . . . . . . . 24

IV. Food Plant Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 1. Elements of Food Plant Design . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

a. General Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 b. New Food Plants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

i. Location...................................... 28 ii. ProductlProcess . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

iii. Food Hygiene. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 iv. Plant Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 v. Food Storage ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

vi. Flexibility..................................... 30 c. Plant Improvement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 d. Plant Expansion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

ix

X HANDBOOK OF FOOD PROCESSING EQUIPMENT

e. Mobile Food Plants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 f. Advanced Food Plants .... . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

2. Good Manufacturing Practices. . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 a. GMPs............................................ 32 b. Food Safety Programs and HACCP. . . . . . . . . . . . . . . . . . . . . . 33

3. Food Plant Economics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 a. Overview of Food Plant Economics . . . . . . . . . . . . . . . . . . . . . 34 b. Economic Analysis of Food Plants. . . . . . . . . . . . . . . . . . . . . . 37

Example 1-1 ........................................... 38 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Chapter 2-Design and Selection of Food Processing Equipment. • . . . . . 47 I. Introduction............................................ 47

II. Sizing and Costing of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 III. Materials of Construction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

1. Metals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 a. Steel............................................. 53 b. Stainless Steels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 c. Aluminum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 d. Copper........................................... 55 e. Other Metals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

2. Plastics-Rubber. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 3. Glass-Ceramics.............. . . . . . . . . . . . . . . . . . . . . . . . . . 56 4. Wood............................................... 57

IV. Fabrication of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 1. Strength of Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

a. General Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 b. Sensitive Construction Points . . . . . . . . . . . . . . . . . . . . . . . . . . 58 c. Proper Engineering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

2. Fabrication and Installation of Equipment . . . . . . . . . . . . . . . . . . . 59 a. General Process Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 b. Food Processing Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 c. Installation of Process Equipment. . . . . . . . . . . . . . . . . . . . . . . 61

V. Hygienic Design of Food Processing Equipment. . . . . . . . . . . . . . . . . 61 1. Hygienic Standards and Regulations . . . . . . . . . . . . . . . . . . . . . . . 62 2. Cleaning of Food Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

VI. Selection of Food Processing Equipment . . . . . . . . . . . . . . . . . . . . . . 66 1. Selection of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

a. Construction Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 i. Dimensions/Weight.............................. 66

ii. Cleaning Facility. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 66 iii. Maintenance................................... 66 iv. Standardization of Spare Parts . . . . . . . . . . . . . . . . . . . . . 67 v. Quality of Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

VI. Firmness/Durability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 vii. Automation.................................... 67

b. Operational Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 i. Reliability..................................... 67

ii. Convenience................................... 68

Contents Xl

iii. Safety........................................ 68 iv. Instrumentation................................. 68 v. Ergonomics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

vi. Efficiency..................................... 69 vii. Effectiveness................................... 69

viii. Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 ix. Environmental Impact. . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

2. Testing of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 3. Equipment Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Example 2-1 ........................................... 70

Directories of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Directories of Food Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73 Exhibitions of Food Process Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . 74 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Chapter 3-Mechanical Transport and Storage Equipment. . . . . . . . . . . 77 I. Introduction............................................ 77

II. Mechnical Transport Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 1. Fluid Food Transport Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . 77

a. Rheological Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 b. Mechanical Energy Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 c. Friction Losses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 d. Pump Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

1. Centrifugal Pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 ii. Positive Displacement Pumps. . . . . . . . . . . . . . . . . . . . . . 88

iii. Other Pumps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 iv. Requirements for Food Pumps . . . . . . . . . . . . . . . . . . . . . 92 v. Pump Selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

e. Pump Auxiliaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 i. Electric Motors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

ii. Mechanical Seals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94 f. Process Piping and Valves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

i. Piping........................................ 95 ii. Valves........................................ 95

g. Hygienic Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 2. Pneumatic and Hydraulic Transport. . . . . . . . . . . . . . . . . . . . . . . . 96

a. Pneumatic Conveyors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 b. Hydraulic Conveyors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

3. Mechanical Conveyors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 100 a. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 b. Selection of Conveyors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 102

i. Uniform Belt Conveyors. . . . . . . . . . . . . . . . . . . . . . . . . . 102 ii. Segmented Belt Conveyors. . . . . . . . . . . . . . . . . . . . . . .. 104

iii. Roll and Skate Wheel Conveyors . . . . . . . . . . . . . . . . . .. 105 iv. Chain Conveyors . . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. 107 v. Screw Conveyors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 108

vi. Vibratory Conveyors. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 110 vii. Hygienic Considerations. . . . . . . . . . . . . . . . . . . . . . . . .. 111

XlI HANDBOOK OF FOOD PROCESSING EQUIPMENT

III. Food Storage Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 1. Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 112 2. Storage of Solids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 113

a. Pallets............................................ 113 b. Box Pallets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

i. Characteristics of Box Pallets . . . . . . . . . . . . . . . . . . . . .. 114 ii. Selection and Use of Box Pallets. . . . . . . . . . . . . . . . . . . 114

c. Bags............................................. 115 i. Introduction................................... 115

ii. Characteristics of Bags. . . . . . . . . . . . . . . . . . . . . . . . . .. 115 d. Bins and Silos. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

i. Characteristics of Bins and Silos. . . . . . . . . . . . . . . . . . .. 117 ii. Construction Considerations. . . . . . . . . . . . . . . . . . . . . .. 118

iii. Emptying of Bins and Silos . . . . . . . . . . . . . . . . . . . . . .. 119 iv. Environmental Considerations . . . . . . . . . . . . . . . . . . . . . 119 v. Material Flowability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120

vi. Safety Considerations. . .. . . . . . . . . . . . . . . . . . . . . . . .. 122 3. Storage of Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 123

a. Vats and Vessels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 i. Basic Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 124

ii. Construction Considerations. . . . . . . . . . . . . . . . . . . . . .. 124 iii. Processing Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 125

b. Tanks............................................ 126 i. Characteristics of Tanks . . . . . . . . . . . . . . . . . . . . . . . . .. 126

ii. Fermentation Tanks. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 127 iii. Tank Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 127

Example 3-1 ........................................... 128 Example 3-2 .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 129

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 130

Chapter 4-Mechanical Processing Equipment. . . . . . . . . . . . • . . . . . . . . 133 I. Introduction............................................ 133

II. Size Reduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 1. Introduction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 2. Cutting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 137

a. General Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 13 7 b. Cutting Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 140

i. Cutting Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 ii. Portable Cutting Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

iii. Cutting Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 • Band Saws. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 • SlicerslDicers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 • Meat Grinders. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 144 • Cutters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 145

c. Selection of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 146 3. Crushing and Grinding .... . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 147

a. Introduction....................................... 147 b. Particle Size Distribution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152

Contents Xlll

c. Crushing and Grinding Equipment. . . . . . . . . . . . . . . . . . . . .. 153 i. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 153

ii. Production between Two Crushing/Grinding Tool. . . . . . . 153 • Roll Crushers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 153 • Roll Mills. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. 155 • Pan Mills. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 • StrainerslPulpers. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 159

iii. Product Impact. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 • Hammer Mills. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 160 • Hammer Crushers . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 161 • Disk Grinders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 161 • Disintegrators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 163

iv. Stresses Due to Relative Particle Motion. . . . . . . . . . . . .. 164 • Rotary Grinders. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 164 • Impeller Attritors. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 165 • Jet Mills. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 166

d. Selection of Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 167 III. Size Enlargement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 167

1. Introduction......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 167 2. Agglomeration Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 170

a. General Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 170 b. Free Structure Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 171

i. General Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 171 ii. Rolling Agglomeration. . . . . . . . . . . . . . . . . . . . . . . . . .. 174

• Rotating Pans. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 174 • Rotating Drums. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 176

iii. Slow Agitation Equipment. . . . . . . . . . . . . . . . . . . . . . .. 176 iv. Vibration Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 177 v. Mixing Agglomeration Equipment . . . . . . . . . . . . . . . . .. 177

• High-Speed Agitation . . . . . . . . . . . . . . . . . . . . . . . . .. 177 • Fluidized Bed Agglomeration . . . . . . . . . . . . . . . . . . .. 179 • Drying Agglomeration. . . . . . . . . . . . . . . . . . . . . . . . .. 182

c. Compression Agglomeration. . . . . . . . . . . . . . . . . . . . . . . . . .. 182 i. General Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 182

ii. Compression Agglomeration Equipment. . . . . . . . . . . . .. 183 • Tableting Equipment. . . . . . . . . . . . . . . . . . . . . . . . . .. 183 • Roll Pressing Equipment. . . . . . . . . . . . . ; . . . . . . . . .. 184 • Pelletizing Equipment . . . . . . . . . . . . . . . . . . . . . . . . .. 186

3. Selection of Agglomeration Equipment. . . . . . . . . . . . . . . . . . . .. 187 IV. Homogenization......................................... 188

1. Introduction.......................... . . . . . . . . . . . . . . .. 188 2. Homogenization Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189

a. Pressure Homogenization. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 189 b. Colloid Mills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 193 c. Rotor-Stator Homogenizers. . . . . . . . . . . . . . . . . . . . . . . . . .. 193 d. Ultrasonic Homogenizers . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 194

V. Mixing and Forming. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 194 1. Fluid Mixing Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 195

a. Agitated Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195

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b. Power of Mixing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 196 c. Industrial Mixers .................................. " 197 d. Food Mixers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 197 e. Selection of Mixers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 198

2. Paste and Dough Mixing Equipment. . . . . . . . . . . . . . . . . . . . . .. 198 3. Forming and Extrusion Equipment. . . . . . . . . . . . . . . . . . . . . . .. 199

a. Forming Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 199 b. Extruders......................................... 201

4. Solids Mixing Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 203 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 203

Chapter 5--Mechanical Separation Equipment .................... 207 I. Introduction............................................ 207

II. Classification Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 209 1. Grading........... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 210 2. Sorting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 211

III. Solid/Solid Separations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 215 1. Screening............................................ 215

a. Sieve Sizes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 215 b. Sieving Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 216

i. Grizzlies/Belt Screens. . . . . . . . . . . . . . . . . . . . . . . . . . .. 217 ii. Trommels..................................... 217

iii. Flat Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 218 iv. Rotating Sifters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 218 v. Screening Cloths. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 218

vi. Magnetic Separators. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 219 vii. Electrostatic Separators. . . . . . . . . . . . . . . . . . . . . . . . . .. 219

c. Sieving of Flour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 219 2. Fluid Classification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 219

a. Air Classifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 219 b. Wet Classifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 223

i. Wet Sieving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 223 ii. Hydrocyclones................................. 223

IV Solid/Liquid Separators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 223 1. Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 224 2. Sedimentation Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 224 3. Industrial Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 225

a. Cake Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 225 i. Plate-and-Frame Filters. . . . . . . . . . . . . . . . . . . . . . . . . .. 226

ii. Vacuum Rotary Filters . . . . . . . . . . . . . . . . . . . . . . . . . .. 227 iii. Pressure Filters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 228 iv. Filtration of Juices . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 229

b. Depth Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 229 i. Sand Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 229

ii. Dual Media Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 230

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iii. Sterile Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 230 4. Centrifuges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 230

a. Centrifugal Separators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 230 b. Filtering Centrifuges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 232

5. Mechanical Expression. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 233 a. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 233 b. Batch Presses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 234

i. Box and Pot Presses . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 234 ii. Curb and Cage Presses. . . . . . . . . . . . . . . . . . . . . . . . . .. 234

c. Continuous Presses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 235 i. Screw Presses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 235

ii. Roller Presses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 235 iiii. Belt Presses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 235

iv. Juice Reamers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 236 d. Fruit Juice Expression Equipment. . . . . . . . . . . . . . . . . . . . . .. 236

i. Apple and Grape Juices. . . . . . . . . . . . . . . . . . . . . . . . .. 237 Rack and Frame Press Wilmes Press Screw Press Bucher Press Belt Press Screening Centrifuge

ii. Citrus Juices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 239 V. Solidi Air Separators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 240

1. Cyclone Separators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 241 2. Bag Filters .... : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 242 3. Air Filters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 244 4. Electrical Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 245 5. Wet Scrubbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 246

VI. Removal of Food-Related Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 246 1. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . " 246 2. Removal of Undesired Own Parts. . . . . . . . . . . . . . . . . . . . . . . .. 247

a. Separations of Animal Products . . . . . . . . . . . . . . . . . . . . . . .. 247 1. Skinning...................................... 247

ii. Dehairing..................................... 247 iii. Cutting....................................... 248 iv. Screening..................................... 248 v. Removal of Mussel Shells. . . . . . . . . . . . . . . . . . . . . . . .. 249

vi. Blood........................................ 249 b. Separations of Plant Materials. . . . . . . . . . . . . . . . . . . . . . . . .. 249

i. Breaking...................................... 250 ii. Dehulling..................................... 250

iii. BrushingIPolishing.............................. 251 iv. Destemming................................... 251 v. Pitting........................................ 251

vi. Coring/Scooping................................ 252

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vii. Cutting/Slicing................................. 253 viii. Peeling....................................... 253

3. Removal of Desired Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 255 4. Food Cleaning Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 255

a. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 255 b. Wet Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 256 c. Dry Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 258

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 258

Chapter 6-Heat Transfer Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . .. 261 I. Introduction............................................ 261

II. Heat Transfer Coefficients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 261 III. Empirical Correlations of h .... . . . . . . . . . . . . . . . . . . . . . . . . . . .. 264

1. General Correlations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 264 2. Simplified Equations for Air and Water. . . . . . . . . . . . . . . . . . . .. 266 3. Heat Transfer Factor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 267

IV Heat Exchangers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 267 1. Overall Heat Transfer Coefficients. . . . . . . . . . . . . . . . . . . . . . .. 268 2. Fouling of Heat Exchangers. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 269 3. Residence Time Distribution. . . . . . . . . . . . . . . . . . . . . . . . . . .. 271 4. Tubular Heat Exchangers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 271 5. Plate Heat Exchangers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 274 6. Agitated Kettles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 277 7. Scraped Surface Heat Exchangers. . . . . . . . . . . . . . . . . . . . . . .. 280 8. Direct Heat Exchangers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 281 9. Baking and Roasting Ovens. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 281

10. Fryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 284 11. Radiation Heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 285

a. Infrared Heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 286 12. Heat Generation Processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 286

a. Microwave and Dielectric Heating. . . . . . . . . . . . . . . . . . . . .. 286 b. Ohmic Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 288

13. Hygienic Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 289 Example 6-1 ........................................... 290 Example 6-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 292 Example 6-3 ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 293

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 294

Chapter 7-Food Evaporation Equipment. . . . . . . . . . . . . . . . . . . . . . . . . 297 I. Introduction............................................ 297

II. Heat Transfer in Evaporators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 298 1. Physical Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 298 2. Heat Transfer Coefficients. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 298 3. Fouling in Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 299 4. Heat Transfer in Film Evaporators. . . . . . . . . . . . . . . . . . . . . . . .. 300

a. Falling Film Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 300 b. Rising Film Evaporators . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 302

5. Falling Film Evaporation of Fruit Juices. . . . . . . . . . . . . . . . . . .. 303

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III. Food Quality Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 304 IV Food Evaporators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 306

1. Material and Energy Balances. . . . . . . . . . . . . . . . . . . . . . . . . . .. 306 2. Long-Residence-Time Evaporators . . . . . . . . . . . . . . . . . . . . . . .. 306

a. Jacketed Vessel Evaporators . . . . . . . . . . . . . . . . . . . . . . . . .. 307 b. Coil Evaporators. . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . .. 307 c. Short-Tube Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 308 d. Forced Circulation Evaporators. . . . . . . . . . . . . . . . . . . . . . .. 308

3. Short-Residence-Time Evaporators. . . . . . . . . . . . . . . . . . . . . . .. 309 a. Long-Tube Vertical Evaporators ...................... , 309 b. Plate Evaporators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 310 c. Agitated Film Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . .. 310 d. Centrifugal Film Evaporators. . . . . . . . . . . . . . . . . . . . . . . . .. 311

V Energy-Saving Evaporation Systems ........... ; ............. , 312 1. Multiple-Effect Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 313 2. Vapor Recompression Evaporators. . . . . . . . . . . . . . . . . . . . . . . .. 315 3. Heat Pump Evaporators ................................ , 318 4. Combined Reverse Osmosis/Evaporation. . . . . . . . . . . . . . . . . . .. 319 5. Water Desalination ................................... , 319 6. Waste-Heat Evaporators ................................ , 319

VI. Evaporator Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 320 1. Evaporator Bodies .................................... , 320

a. LTV Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 320 b. Plate Evaporators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 321

2. VaporlLiquid Separators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 321 3. Condensers.......................................... 322 4 Vacuum Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 323 5. Evaporator Control ................................... , 324 6. Testing of Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 324 7. Hygienic Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 324 Example 7-1 ........................................... 325

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 328

Chapter 8-Food Dehydration Equipment. . . . . . . . . . . . . . . . . . . . . . . . . 331 I. Introduction............................................ 331

II. Principles of Drying ..................................... , 332 1. Psychrometric Calculations ............................. , 332 2. Drying Rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 333 3. Food Dehydration Technology. . . . . . . . . . . . . . . . . . . . . . . . . . .. 338

III. Design and Selection of Food Dryers ........................ , 339 1. Heat and Mass Transfer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 339 2. Modeling and Simulation of Dryers. . . . . . . . . . . . . . . . . . . . . . .. 342 3. Design of Industrial Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 344 4. Selection of Industrial Dryers . . . . . . . . . . . . . . . . . . . . . . . . . . .. 345 5. Commercial Food Drying Equipment. . . . . . . . . . . . . .. . . . . . . .. 347

a. Sun Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 348 b. Solar Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 349 c. Bin, Silo, and Tower Dryers. . . . . . . . . . . . . . . . . . . . . . . . .. 350

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d. Tray/Cabinet Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 352 e. Tunnel Dryers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 353 f. Conveyor Belt Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 353 g. Rotary Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 355 h. Fluid Bed Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 356 i. Spouted Bed Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 358 j. Pneumatic/Flash Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 358 k. Agitated Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 361 1. Spray Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 361 m. Drum Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 364 n. Vacuum and Freeze Dryers. . . . . . . . . . . . . . . . . . . . . . . . . .. 365

6. Special Food Dryers .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 367 a. Microwave and Dielectric Dryers. . . . . . . . . . . . . . . . . . . . .. 368 b. Infrared Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 369 c. Tumbling Dryers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 369 d. Centrifugal Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 369 e. Explosion Puffing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 370 f. Foam-Mat Drying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 370 g. Acoustic Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 370 h. Osmotic Dehydration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 370

7. Hygienic and Safety Considerations. . . . . . . . . . . . . . . . . . . . . . .. 371 IV. Energy and Cost Considerations of Drying. . . . . . . . . . . . . . . . . . . .. 372

1. Heat Sources for Drying. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 373 2. Heat Recovery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 373 3. Energy Efficient Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 374

a. Superheated Steam Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . .. 374 b. Heat Pump Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 374 c. Impingement Dryers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 374

4. Cost Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 375 Example 8-1 ........................................... 376

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 377

Chapter 9-Refrigeration and Freezing Equipment . . . . . . . . . . . . . . . . . 383 I. Introduction............................................ 383

II. Refrigeration Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 384 1. Refrigeration Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 384 2. Compressors......................................... 389

a. Reciprocating Compressors. . . . . . . . . . . . . . . . . . . . . . . . . . .. 389 i. General Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . .. 389

ii. Lubrication and Oil Separation. . . . . . . . . . . . . . . . . . . .. 392 iiii. Selection of Reciprocating Compressors. . . . . . . . . . . . .. 393

b. Rotary Compressors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 393 c. Centrifugal Compressors. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 394 d. Screw Compressors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 394

3. Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 395 a. Forced Convection Air Coolers. . . . . . . . . . . . . . . . . . . . . . . .. 396

i. General Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . .. 396 ii. Defrosting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 399

Contents XIX

b. Bath and Tube Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . .. 400 c. Shell and Tube Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . .. 401 d. Shell and Coil Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . .. 402 e. Double-Pipe Evaporators. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 403 f. Baudelot Evaporators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 403 g. Double-Wall Evaporators . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 404 h. CoolinglFreezing Evaporators for Solids. . . . . . . . . . . . . . . . .. 404 i. Improvement of Heat Transfer in Evaporators. . . . . . . . . . . . .. 405

4. Condensers.......................................... 405 a. Tube Condensers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 405 b. Evaporative Condensers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 406 c. Tower Condensers ................................. " 406 d. Air Condensers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 407

5. Capacity Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 407 III. Cooling of Foods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 408

1. Chilling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 408 2. Cooling Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 411

a. Cooling of Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 411 i. Hydrocooling.................................. 411

ii. Vacuum-Cooling................................ 414 iii. Surface Contact Cooling ........................ " 414 iv. Tunnel Cooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 414

b. Cooling of Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 415 i. Plate Heat Exchangers . . . . . . . . . . . . . . . . . . . . . . . . . .. 415

ii. Scraped Surface Heat Exchangers. . . . . . . . . . . . . . . . . .. 416 iii. Jacketed Vessels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 416 iv. Shell and Coil Equipment. . . . . . . . . . . . . . . . . . . . . . . " 416 v. Vacuum Cooling Equipment. . . . . . . . . . . . . . . . . . . . . .. 416

vi. Combination Cooling with Mixing. . . . . . . . . . . . . . . . .. 416 Iv. Freezing of Foods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 416

1. Freezing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 416 2. Freezing Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 422

a. Air Freezing Equipment ............................ " 423 i. Tunnel Freezers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 423

ii. Fluidized Bed Freezers. . . . . . . . . . . . . . . . . . . . . . . . . .. 424 iii. Belt Feezers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 424

• Straight Belts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 425 • Elevator System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 426 • Curved Belts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 426

b. Cold Surface Freezing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 427 c. Liquid Freezing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 428

i. Liquid Freezers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 428 ii. Frozen Pellets ................................ " 428

iii. Cryogenic Liquids . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 429 3. Thawing Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 431

a. Convective Methods of Thawing . . . . . . . . . . . . . . . . . . . . . . .. 431 b. Vacuum Thawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 432 c. Contact Thawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 432

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d. Electrical Thawing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 432 V. Cold Storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 434

1. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 434 2. Reduction of Weight Loss. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 438

a. Temperature Adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 438 b. Humidification..................................... 439 c. Controlled Atmosphere. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 439

VI. Ice Manufacturing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 441 Example 9-1 ........................................... 448

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 449

Chapter 100Thermal Processing Equipment. . .... .... . ... . . ...... 451 I. Introduction............................................ 451

II. Kinetics of Thermal Inactivation. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 452 1. Inactivation of Microorganisms and Enzymes. . . . . . . . . . . . . . .. 452 2. Thermal Damage to Food Components. . . . . . . . . . . . . . . . . . . .. 454

III. Heat Transfer Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 455 1. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 455 2. Unsteady-State Heat Transfer . . . . . . . . . . . . . . . . . . . . . . . . . .. 456

IV. Thermal Process Calculations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 458 1. In-Container Sterilization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 458

a. General Method ................................... , 459 b. Formula Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 459 c. Commercial Sterility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 461

2. Continuous Flow Thermal Processes. . . . . . . . . . . . . . . . . . . . . .. 461 a. One-Phase Fluid Foods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 461 b. Two-Phase Foods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 462

i. Fluid Flow and Heat Transfer Considerations . . . . . . . . .. 462 ii. Validation of the Aseptic Processes. . . . . . . . . . . . . . . . .. 463

V. Thermal Processing Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 464 1. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 464 2. In-Container Sterilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 464

a. Canning Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 464 1. Receiving..................................... 465

ii. Washing...................................... 466 iii. Inspecting/Sorting............................... 466 iv. Grading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 466 v. Blanching..................................... 466

VI. Peeling....................................... 467 vii. Cutting....................................... 467

viii. Filling........................................ 467 ix. Exhausting.................................... 468 x. Closing....................................... 468

xi. Sterilizing..................................... 468 xii. Labeling/CasingIWarehousing...................... 468

xiii. Can Sizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 469 xiv. Typical Thermal Process Times. . . . . . . . . . . . . . . . . . . .. 469

b. Batch Sterilizers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 470 i. Still Retorts .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 470

Contents XXI

ii. Batch Rotary Sterilizers. . . . . . . . . . . . . . . . . . . . . . . . .. 472 iii. Crateless Retorts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 473 iv. Retorts for Glass and Flexible Containers. . . . . . . . . . . .. 473

c. Continuous In-Container Sterilizers .................... , 474 i. Rotary Cooker/Coolers. . . . . . . . . . . . . . . . . . . . . . . . . .. 474

ii. Hydrostatic Sterilizers. . . . . . . . . . . . . . . . . . . . . . . . . . .. 475 d. New In-Container Sterilizers. . . . . . . . . . . . . . . . . . . . . . . . . .. 476

i. Circulating Water and Steam Sterilizers ............. , 476 ll. Track Flow Sterilizers. . . . . . . . . . . . . . . . . . . . . . . . . . .. 477

iii. "Flash 18" Sterilizers . . . . . . . . . . . . . . . . . . . . . . . . . . .. 478 iv. Flame Sterilizers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 478

3. Continuous Flow (UHT) Sterilizers. . . . . . . . . . . . . . . . . . . . . . .. 479 a. General Aspects ..................... ; . . . . . . . . . . . . .. 479 b. Pumping.......................................... 481 c. Direct Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 481 d. Indirect Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 482

i. Plate Heat Exchangers . . . . . . . . . . . . . . . . . . . . . . . . . .. 482 ii. Tubular Heat Exchangers . . . . . . . . . . . . . . . . . . . . . . . .. 482

iii. Scraped Surface Heat Exchangers. . . . . . . . . . . . . . . . . .. 482 iv. Ohmic Heating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 483 v. Aseptic Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 483

4. Thennal Pasteurizers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 483 a. General Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 483 b. In-Container Pasteurizers . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 484 c. Continuous Flow (HTST) Pasteurizers . . . . . . . . . . . . . . . . . .. 485

5. Thennal Blanchers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 488 6. Hygienic Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 489 Example 10-1 .......................................... 490

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 491

Chapter ll-Mass Transfer Equipment. . . . . . . . . . . . . . . . . . . . . . . . . .. 493 I. Introduction............................................ 493

II. Distillation Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 495 1. VaporlLiquid Equilibria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 495

a. Activity Coefficients and Relative Volatilities. . . . . . . . . . . . .. 495 b. Nonideal Mixtures and Azerotropes . . . . . . . . . . . . . . . . . . . .. 496 c. Volatile Food Aromas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 498

2. Detennination of Equilibrium Stages. . . . . . . . . . . . . . . . . . . . . .. 501 a. Graphical Methods ................................ " 503 b. Analytical Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 505 c. Column Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 506

3. Food Distillation Equipment ........................... " 507 a. Ethanol Distillation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 507 b. Essence Recovery Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 509

i. Stripping of Aromas. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 510 ii. Fractionation of Aromas ........................ " 511

c. Spinning Cone Stripping Column. . . . . . . . . . . . . . . . . . . . . .. 512 d. Molecular Distillation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 513

III. Solvent Extraction/Leaching Equipment ..................... " 513

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1. LiquidlLiquid and Liquid/Solid Equilibria. . . . . . . . . . . . . . . . . .. 514 2. Determination of Equilibrium Stages. . . . . . . . . . . . . . . . . . . . . .. 517 3. Mass Transfer Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . .. 518 4. Food Extraction and Leaching Equipment. . . . . . . . . . . . . . . . . .. 519

IV GaslLiquid Absorption Equipment. . . . . . . . . . . . . . . . . . . . . . . . . .. 522 1. Gas/Liquid Equilibria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 522 2. Determination of Equilibrium Stages. . . . . . . . . . . . . . . . . . . . . .. 523

a. Tray Columns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 523 b. Packed Towers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 524

3. Gas Absorption and Stripping Equipment. . . . . . . . . . . . . . . . . .. 525 a. Agitated Vessels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 526 b. Multistage Columns and Packed Towers. . . . . . . . . . . . . . . . .. 526 c. Gas Scrubbers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 527

V Adsorption and Ion-Exchange Equipment. . . . . . . . . . . . . . . . . . . . .. 527 1. Adsorption Equilibria and Mass Transfer. . . . . . . . . . . . . . . . . . .. 527 2. Adsorption Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 529 3. Ion-Exchange Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 530 4. Food Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 530

a. Water Treatment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 530 b. Recovery of Valuable Components . . . . . . . . . . . . . . . . . . . . .. 531 c. Removal of Undesirable Components. . . . . . . . . . . . . . . . . . .. 532

VI. Crystallization from Solution Equipment. . . . . . . . . . . . . . . . . . . . .. 532 1. Solubility Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 533 2. Nucleation and Mass Transfer. . . . . . . . . . . . . . . . . . . . . . . . . . .. 533 3. Industrial Crystallizers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 534 Example 11-1 .......................................... 535 Example 11-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 536

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 538

Chapter 12-Equipment for Novel Food Processes. . . . . . . . . . . . . . . . .. 541 I. Introduction............................................ 541

II. Membrane Separation Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . .. 542 1. Mass Transfer Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . .. 542 2. Membranes and Membrane Modules. . . . . . . . . . . . . . . . . . . . . .. 544 3. Membrane Separation Systems. . . . . . . . . . . . . . . . . . . . . . . . . .. 545

a. General Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 545 b. Design of Membrane Systems. . . . . . . . . . . . . . . . . . . . . . . . .. 546

4. Reverse Osmosis and Nanofiltration . . . . . . . . . . . . . . . . . . . . . .. 546 a. RO Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 547 b. Food Applications ofRO . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 547

5. Ultrafiltration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 548 a. UF Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 549 b. Food Applications of UF. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 550

6. Microfiltration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 552 a. MF Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 552 b. Food Applications of MF . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 553

7. Pervaporation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 554

Contents XXlll

8. Electrodialysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 555 III. Supercritical Fluid Extraction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 555

1. Supercritical Fluids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 556 2. SCF Extraction Processes and Equipment. . . . . . . . . . . . . . . . . .. 557 3. SCF Extraction in Food Processing. . . . . . . . . . . . . . . . . . . . . . .. 558

IV Crystallization from Melt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 558 1. Freeze Concentration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 559

a. Crystallization of Ice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 559 b. Ice Separation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 561 c. Food Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 561

2. Fat Fractionation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 562 a. Dry Fractionation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 562 b. Detergent Fractionation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 562 c. Solvent Fractionation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 563

V. Nonthermal Food Preservation. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 563 1. Food Irradiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 563

a. Review of Food Irradiation. . . . . . . . . . . . . . . . . . . . . . . . . . .. 564 b. Food Preservation by Irradiation. . . . . . . . . . . . . . . . . . . . . . .. 564 c. Sources of Food Irradiation. . . . . . . . . . . . . . . . . . . . . . . . . . .. 567 d. Cost of Food Irradiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 569

2. High-Pressure Processing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 570 3. Pulsed Electric Field Processing . . . . . . . . . . . . . . . . . . . . . . . . .. 571

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 571

Chapter 13-Food Packaging Equipment .... . . . . . . . . . . . . . . . . . . . .. 575 I. Introduction............................................ 575

1. General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 575 2. Packaging Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 577

a. Technical Considerations . . . . . . . . .. . . . . . . . . . . . . . . . . . .. 579 b. Safety Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 579 c. Technological Considerations. . . . . . . . . . . . . . . . . . . . . . . . .. 580 d. Economic Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 580 e. Ecological Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 580

3. Packages and Packaging Materials. . . . . . . . . . . . . . . . . . . . . . . .. 581 a. Metal............................................ 581 b. Glass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 582 c. Paper, Carton, and Cardboard. . . . . . . . . . . . . . . . . . . . . . . . .. 583 d. Plastics... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 584

II. Preparation of Food Containers. . . .. . . . . . . . . . . . . . . . . . . . . . . . .. 587 1. Unscrambling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 587 2. Fabrication and Forming of Packages. . . . . . . . . . . . . . . . . . . . . .. 587

a. Metal Containers .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 587 b. Cartons and Cardboard Packages. . . . . . . . . . . . . . . . . . . . . .. 588 c Film-Based Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 588

i. Tube Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 588 ii. Pouch Packages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 590

iii. Thermoformed Packages . . . . . . . . . . . . . . . . . . . . . . . .. 591

XXIV HANDBOOK OF FOOD PROCESSING EQUIPMENT

iv. Blow Mold Packages . . . . . . . . . . . . . . . . . . . . . . . . . . .. 592 III. Filling Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 593

1. General Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 593 2. Dosing...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 598 3. Product Transfer Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 601 4. Valves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 603 5. Weighing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 605

IV. Closing Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 608 1. Closing of Food Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 608 2. Glass Closures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 609 3. Closing of Metallic Containers. . . . . . . . . . . . . . . . . . . . . . . . . .. 609 4. Closing of Plastic Packages. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 610 5. Closing of Cartons and Cardboard. . . . . . . . . . . . . . . . . . . . . . . .. 611

V. Aseptic Packaging. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 612 VI. Group Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 617

1. Grouping of Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 617 2. Wrapping.............. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 618 3. Palletizing............ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 620

References. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. 621

Appendix A-Notation and Conversion of Units .................... 627 I. Notation............................................... 627

II. Conversion to SI Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 630

Appendix B-Selected Tbermopbysical Properties . . . . . . . . . . . . . . . . .. 633

Appendix C-Control of Food Processing Equipment. . . . . . . . . . . . . . .. 639

Appendix D-Food Plant Utilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641 I. Industrial Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 641

II. Steam Boilers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 641 III. Air Moving and Vacuum Equipment. . . . . . . . . . . . . . . . . . . . . . . . .. 642 IV. Electrical Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 642 V. Waste Treatment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 643

1. Wastewater Treatment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 643 2. Solid Wastes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 643 3. Gas Pollution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 644

Appendix E-Manufacturers and Suppliers of Food Equipment . . . . . .. 645

Index ...................................................... 687