Fruit and vegetables: harvesting, handling, and storage

Fruit and Vegetables

Fruit and Vegetables Harvesting, Handling and Storage

A. K. Thompson

© 2003 by Blackwell Publishing Ltd Editorial Offices: Blackwell Publishing Ltd, 9600 Garsington Road, Oxford OX4 2DQ, UK Tel: +44 (0)1865 776868 Iowa State Press, a Blackwell Publishing Company, 2121 State Avenue, Ames, Iowa 50014-8300, USA Tel: +1 515 292 0140 Blackwell Publishing Asia, 550 Swanston Street, Carlton, Victoria 3053, Australia Tel: +61 (0)3 8359 1011 The right of the Author to be identified as the Author of this Work has been asserted in accordance with the Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher. First published 2003 by Blackwell Publishing Ltd Library of Congress Cataloging-in-Publication Data Thompson, A. K. (A. Keith) Fruit and vegetables : harvesting, handling, and storage / A.K. Thompson. p. cm. Includes bibliographical references and index. ISBN 1-4051-0619-0 (Hardback : alk. paper) 1. Fruit--Postharvest technology. 2. Vegetables--Postharvest technology. I. Title. SB360.T45 2003 634'.046--dc21 2003009287 ISBN 1-4051-0619-0 A catalogue record for this title is available from the British Library Typeset in Minion and produced by Gray Publishing, Tunbridge Wells, Kent Printed and bound in the UK using acid-free paper by The Bath Press, Bath, Avon For further information on Blackwell Publishing, visit our website: www.blackwellpublishing.com

Contents (Colour plate section falls between pages 206 and 207) Preface Acknowledgements

xv xvii

1.

Preharvest factors on postharvest life Introduction Nutrients Organic production Rootstock Light Day length Temperature Water relations Tree age Flowering time Harvest time Preharvest infection Chemical treatments

1 1 1 3 4 5 5 5 6 6 6 6 7 7

2.

Assessment of crop maturity Introduction Field methods Postharvest methods

9 9 9 12

3.

Harvesting and handling methods Introduction Crop damage Harvesting Field transport

19 19 19 21 24

4.

Precooling Introduction Heat removal Precooling methods

25 25 26 26

5.

Packaging Introduction Types of packaging Package recycling Modified atmosphere packaging

31 31 32 38 38

vi

Contents

6.

Postharvest treatments Introduction Minerals Astringency removal Antioxidants Sprout suppressants Fruit coating Antiethylene Salicylic acid Curing Hot water treatment Vapour heat treatment Degreening

47 47 47 48 48 48 49 51 51 51 52 52 52

7.

Storage Store management and organization Store design and method Refrigerated storage Controlled atmosphere stores Hypobaric storage

53 53 54 59 61 69

8.

Disease control Introduction Legislation Microorganism control Chemical application methods Non-fungicidal methods of disease control

71 71 71 72 73 75

9.

Safety Introduction Micotoxins Bacterial toxins Safety in controlled atmosphere stores Toxicity of packaging material Packhouse safety

80 80 81 82 84 85 85

10.

Fruit ripening conditions Introduction Changes during fruit ripening Controlled atmosphere storage on ripening Design of ripening rooms Ethylene on ripening Sources of ethylene Alternative gases to ethylene

86 86 87 91 92 92 93 95

Contents

vii

11.

Marketing and transport Marketing Marketing systems Cooperative marketing associations Market analysis Branding National transport International trade Cold chain Transport by sea International transport by airfreight Temperature monitoring International quarantine

97 97 98 100 101 101 102 103 103 103 110 111 112

12.

Postharvest technology of fruits and vegetables Introduction Acerolas Ackee, akee African breadfruit Amelanchier Amaranth American grapes Anise, anis Añus, cubios Apples Apricot Arracacha, Peruvian parsnip Arrowroot Asian pears, Japanese pears, nashi Asian spinach Asparagus Atemoyas Aubergines, egg plants Avocados, alligator pear, midshipmen’s butter Babacos Bamboo shoots Banana passionfruit Bananas Barbados cherries, West Indian cherries Beefsteak fungus Beetroots, red beet Belle apples, Jamaican honeysuckle, water lemons Biriba, wild soursop Bitter gourd, pepino, kerela, bitter cucumber, balsam pear Bitter yam, cluster yam Blackberries, brambles Blackcurrants Black radish Black sapotes

115 115 115 116 116 117 117 117 117 118 118 134 135 136 136 137 139 140 141 142 147 148 148 149 166 166 167 168 168 168 169 169 170 171 172

viii Contents

Blueberries, bilberries, whortleberries Blewit, field blewit Bottle gourds, white flowered gourds Boysenberries Breadfruits Broad beans, horse beans, Windsor beans Broccoli, calabrese Brussels sprouts Cabbages Caimetos, star apples Calamondnis, Philippine limes Canistel, egg fruit Cape gooseberries, physalis, Peruvian cherry Capsicums, sweet peppers, bell peppers Carambola, star fruit Carrots Cashew apples Cassava, monioc, tapioca, yuca Cauliflower Cauliflower fungus Celeriac, turnip rooted celery Celery Cep, penny bun boletus Chanterelles Chard, spinach beet Chayotes, christophines, chocho Cherimoyas Cherries, sweet cherries Chervil Chicory, whitloof, radicchio Chilles, hot peppers, peppers, cherry peppers, bird chillies Chinese artichokes Chinese bayberries Chinese cabbage Chinese chives Chinese kale, kale Chinese pears Chinese radishes, Japanese radishes Chinese water chestnut, biqi Chinese yams Chives Citron Clementines Cloudberries, baked-appled berries Coconuts, waternuts, jelly coconuts Collards, kale Coriander Courgettes, summer squash, zucchini, baby marrow Cranberries

172 173 173 174 174 175 176 177 178 179 180 180 180 181 183 184 186 186 189 191 191 192 193 193 194 194 195 195 196 197 198 198 199 199 200 200 201 201 201 202 202 203 203 203 204 204 205 205 206

Contents

Cress, watercress Cucumber Custard apples, bullock’s heart Damsons Dates Dewberries Dill Durians Easy peeling citrus fruits Elderberries Elephant foot yam, elephant yam, suran Emblic, Indian gooseberries Endives, escaroles, frisee Enoki-take mushrooms, winter mushroom, velvet shank Fairy ring toadstool Feijoas, pineapples guava Fennel Field mushroom Fig leaf gourds, malibar gourds Figs Gages, green gages Garlic Genips, Spanish limes Giant taro Ginger Globe artichokes Golden apple, otaheite apple Gooseberries Governor’s plum Granadillas, giant granadillas Granadillos, sweet granadillas Grapes Grapefruits Greater yam, Lisbon yam, white yam, water yam, Asiatic yam Green beans, kidney beans, snap beans, common beans Guavas Hawthorne Hog plum, yellow mombin Horn of plenty Horse mushroom Horseradish Huckleberries Hyssop Intoxicating yam, Asiatic bitter yam Jaboticaba Jackfruit, jaca Jerusalem artichoke Jew’s ear Jujube, Chinese jujube

ix

207 208 209 210 210 213 213 213 215 215 215 216 216 216 217 217 218 218 218 218 220 220 221 221 221 222 223 223 224 224 224 225 227 229 230 232 234 234 234 234 234 235 235 235 236 236 237 237 237

x Contents

Jujube, Indian jujube, ber Kale Kiwanos, horned melons, melano Kiwifruits, Chinese gooseberries, yang tao Kohlrabi, turnip rooted cabbage Kumquats Langsat, lanzon, duku Leeks Lemons Lemon balm Lesser yam, Asiatic yam, lesser Asiatic yam Lettuces Lima beans, butter beans, Burma beans Limes Limequats Litchi, lychee Loganberries Longan Longkong, longong Loquats, Japanese medlars Lotus roots Lovi lovi Maitake Malay apple, pomerac, jambos, Malacca apple Mamey, mamay apple, mammey apple Mandarins Mangoes Mangosteen Marrow, squash Matricaria Medlar Melons, cantaloupes, musk melons Methi Mint Monstera Mora, Andes berry Morles Mulberries Mume, Japanese apricot Mushrooms, cultivated mushroom Mustard, white mustard Nameko Naranjilla, lulo, toronja Nectarines Oca Okra, gumbo, lady’s finger Olives Onions, bulb onions Oranges

238 239 239 239 241 242 242 243 244 246 247 247 250 251 253 253 255 255 257 257 258 258 258 258 259 259 260 267 268 270 270 270 273 273 273 273 274 274 274 275 278 278 278 279 279 280 281 282 286

Contents xi

Ortanique, temple oranges, murcotts Oyster mushrooms, hiratake mushroom Papa criolla, criolla Papayas, pawpaws Papayuela, mountain papaya Parasol mushrooms, parasol fungus Parsley Parsnips Passionfruits, maracuya Pe-tsai, pak choi, pak choy, celery cabbage Peaches Pears Peas, garden peas, mange tout, snow peas, sugar peas Pepinos, mishqui, tree melons Persimmons, kaki, sharon fruit, date plums Pineapples Pink-spored grisette, rose-gilled grisette Pitahaya, dragon fruit Plantains Plums Pomegranates Potatoes Potato yams Prickly pear, tuna, Indian fig, barberry fig, cactus fruit Pummelos, pumelos, pomelo, shaddock Pumpkin Queensland arrowroot, edible canna Quinces Radishes, salad radishes Rambutan Raspberries Redcurrants, whitecurrants Red whortleberries, cowberries, mountain cranberries Rhubarb Rose apple, pommarosa Saffrom milk cap Salak, snake fruit Salsify Sapodillas, sapota, zapota, chico chiko Sapote mamey, mamey zapote Satsumas Savory, summer savory Scarlet runner beans, runner beans Scorzonere Seville oranges, bitter oranges Shaggy ink cap, lawyer’s wig Shallots Shiitake Sloes

290 290 291 291 294 294 294 295 296 297 297 299 302 304 305 306 308 309 309 311 313 314 320 320 321 322 322 322 323 324 325 326 326 327 327 327 328 328 328 330 331 332 332 332 333 333 334 334 335

xii Contents

Snake gourds Sorrel, Jamaican sorrel, roselle Sorrel, French sorrel Sour cherries Soursop, graviola, guanabana Spanish plum, Jamaican plum, red mombin Spinach Spring onions, green onions, escallion, scallions Strawberries Strawberry guava, cattley guava Straw mushrooms, paddy straw mushrooms Sugar cane, noble cane Summer white button mushroom Swamp taro, giant swamp taro, gallan Swedes, rutabagas Sweetcorn, babycorn Sweet passionfruit Sweet potatoes Sweetsops, sugar apples, custard apples Tamarillos, tree tomatoes Tamarind Tangerines Tannia, new cocoyam Taro, dasheen, eddoe, cocoyam, malanga, old cocoyam Tayberries Tomatoes Topee tambo Truffles Turnips Turnip greens Turnip rooted parsley, hamburgh parsley Uglifruits, mineolas, minneolas, tangelos Ullocu, ulloco Velvet shank Watermelon Water spinach, tong cai, kang kong West Indian gooseberries, otahiete gooseberries White radishes, Japanese radishes, mooli, daikon White sapote, zapote White yams, negro yams, guinea yams Wild cucumbers, pepinos Winged beans Wood blewits Wood mushroom Yacon, jiquima, aricuma Yam bean, jicama Yams Yampies, cush cush, elephant yams, Indian yams Yanagimatsutake mushrooms

335 336 336 336 337 337 337 338 339 341 342 342 342 343 344 344 346 347 348 349 350 351 351 351 353 353 357 357 357 358 358 358 359 359 359 361 361 361 361 362 363 363 364 364 364 365 366 366 367

Contents xiii

Yellow yams, twelve months yams Youngberries Zapotes chupa chupa

367 368 369

Appendix: glossary of terms Abbreviations Carbon dioxide and oxygen in controlled atmosphere stores Concentration of chemicals and ethylene in a store Film thickness Humidity Hypobaric storage

371 371 371 371 371 372 372

References

373

Index

445

To Elara, Maya, Ciaran, Caitlin and Cameron to whom I owe much more than they will ever know

Preface The technology involved in getting fresh produce from the field to the consumer has been the subject of detailed research for over a century. It is enormously complicated because many of the crops are highly perishable and variable. This variability militates against simple solutions. The fresh produce trade would prefer not to be involved with this variation and complexity: they would prefer to be able to look up their particular crop on a chart, which will say it should be harvested, packaged and stored in a certain way. Information in this form is readily available but will rarely give the best results in terms of preserving the quality of the crop. The objective of this book is to provide a range of options from which the produce technologist can select. Additionally it puts into context our current state of knowledge on postharvest technology and thus identifies areas where research is needed. The work is based on a selective review of the literature and my experiences since I was first formally involved in postharvest technology in 1967. Since that time postharvest technology has taken me all over the world doing short consultancies and long-term assignments, of up to three years, meeting particular challenges in research, training and development of the fruit and vegetable industry. Although much of my time has been spent as an academic and government or United Nations adviser, I have always worked closely with the horticultural industry. The information in this book and the way that it is presented are therefore largely what is required by the industry. Also, there is increasing pressure for universities to provide graduates who are more relevant to the needs of industry and most students of postharvest technology will eventually work in the industry or in some way be associated with it; so the book will also serve their needs. For the produce technologists in Europe and North America, the range of fruit and vegetables with which they come into contact is constantly increasing. One of the reasons for this is that retailers are competing for customers and therefore they need constantly to find an edge to attract new customers. Fresh fruit and vegetables are a major factor in showing that

one retailer is different; the fresh produce section is usually the first section inside a supermarket. This book therefore covers the whole range of produce from the major sellers to those that are of minor importance in industrial countries and to those that may become important in the future. The parts on the latter group of produce (often referred to by names such as ‘exotic’ or ‘queer gear’ by the trade in the UK) will also give some ideas to those in the trade of what crops might be developed for the future. During the Second World War, Winston Churchill concluded a long and rambling oration with the words, ‘I am sorry to have made such a long speech, but I did not have time to write a shorter one’. During her time as British Prime Minister, Margaret Thatcher always insisted that briefing notes from officials should be no longer than half a page. There is an enormous literature on postharvest science and technology of fruits and vegetables. Scientists have written much of this for other scientists not only to contribute to the scientific literature, but also to gain recognition or even promotion. To extract from this literature information that is useful to the industry in a concise form is a prohibitive task. There are high losses and variable quality in the fruits and vegetables offered to the consumer. One solution to this problem is to provide those concerned with the technology of marketing these crops with easily accessible information. This, in part, means information that is brief, easily understood and directly to the point. In this book I have tried to achieve this. I have searched relevant reviews and original research papers in order to extract relevant data and present it in a form that should be easily accessible to all those working in the industry. The book is an update of one I wrote with Brian Clarke, which was published by Blackwells in 1996, but it is more focused on technology. The final chapter is based on the collected memoirs of Professor C.W. Wardlaw, published in 1938, when he and his colleagues did so much research on the postharvest technology of fruit and vegetables and the work of Dr J.M. Lutz and Dr R.E. Hardenburg published in the United States Department of Agriculture Bulletin 66.

Acknowledgements To Mr Allen Hilton, Dr Wei Yuqing, Dr Dick Sharples, Professor Don Tindall, Dr Sulafa Musa, Dr Bob Booth, Dr Andy Medlicott, Dr Robin Tillet, Dr James Ssemwanga, Mr David Bishop, Mr Devon Zagory, Mr. Tim Bach, Silsoe Research Institute, FAO Rome, WIBDECO St. Lucia and Positive Ventilation Limited for use of photographs and other illustrative material. To Dr Graham Seymour, Dr John Stow, Mr John Love,

Dr Nick Smith, Mr Derek Plilchar, Mr Gary Bradbury and Mr Graham Clampin for technical help and advice. I wish to express my deep appreciation to Dr Chris Bishop who proof-read the book due to difficulties of communication while I was working in a village in the Central Lowlands of Eritrea.

Fruit and Vegetables: Harvesting, Handling and Storage A. K. Thompson Copyright © 2003 by Blackwell Publishing Ltd

1

Preharvest factors on postharvest life

Introduction The quality of a crop at harvest can have a major effect on its postharvest life. There are numerous factors involved and these factors frequently interact, giving complex interrelationships. In tree crops, fruit produced on the same tree and harvested at the same time may behave differently during marketing or when stored. The issues that influence produce quality include obvious things, such as harvest maturity and cultivar or variety, but also the climate and soil in which it was grown, chemicals which have been applied to the crop and its water status. Many of these factors can also interact with time such as when fertilizers or irrigation is applied or the weather conditions near to the time of harvest. An equation was proposed (David Johnson, personal communication 1994) to predict the probability of low temperature breakdown in apples in storage where variance accounted for 56%. This equation was based on preharvest factors such as temperature, rainfall and nutrient level in the leaves and fruit of the trees as follows: 8.2 + 4.5 Tmax [J] – 2.9 Tmax [A – S] + 0.11 rain [A + S] – 16.4 leaf N – 3.9 fruit P

rain [A + S] = total rainfall in August and September leaf N = level of nitrogen in the leaves fruit P = level of phosphorus in the fruit.

Nutrients The soil type and its fertility affect the chemical composition of a crop. Excess or deficiency of certain elements from the crop can affect its quality and its postharvest life. Many storage disorders of apples are associated with an imbalance of chemicals within the fruit at harvest (Table 1.1). The relation between the mineral composition of fruits and their quality and behaviour during storage is not always predictable (Table 1.2), but in some cases the mineral content of fruits can be used to predict storage quality. For good storage quality of Cox’s Orange Pippin apples it was found that they required the following composition (on a dry matter basis) for storage until December at 3.5°C or 4.5% calcium with Table 1.1 Storage disorders and other storage characteristics of Cox’s Orange Pippin apples in relation to their mineral content (source: Rowe 1980) Composition in mg per 100 g

where: = mean daily maximum temperature Tmax [J] in June Tmax [A – S] = difference in mean daily maximum temperature in August and September

Disorder Bitter pit Breakdown Lenticel blotch pit Loss of firmness Loss of texture

N

P 80