co-product recovery in food processing
Environmentally-friendly food processing
(ISBN-13: 978-1-85573-677-1; ISBN-10: 1-85573-677-2)
With both regulation and consumer pressure increasing, the food industry needs to ensure that its production methods are sustainable and sensitive to environmental needs. This important collection reviews ways of analysing the impact of food processing operations on the environment, particularly life cycle assessment (LCA), and techniques for minimising that impact. The fi rst part of the book looks at the application of LCA to the key product areas in food processing. Part II then discusses best practice in such areas as controlling emissions, waste treatment, energy effi ciency and biobased food packaging.
Maximising the value of marine by-products
(ISBN-13: 978-1-84569-013-7; ISBN-10: 1-84569-013-3)
Overexploitation and declining fi sh stocks are creating an urgent need for better utilisation of seafood by-products. Currently a large proportion of the fi sh catch is wasted, even though marine by-products contain valuable protein and lipid fractions, vitamins, minerals and other bioactive com- pounds benefi cial to human health. Edited by a leading authority and bringing together key experts in the fi eld, this collection covers marine by-product characterisation, recovery, processing techniques, food and non-food applications, providing essential information for those involved in seafood by-product valorisation.
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Handbook of waste management and co-product recovery
in food processing
Volume 1
Edited by Keith Waldron
Cambridge England
www.woodheadpublishing.com
Published in North America by CRC Press LLC, 6000 Broken Sound Parkway, NW, Suite 300, Boca Raton FL 33487, USA
First published 2007, Woodhead Publishing Limited and CRC Press LLC
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Contributor contact details . . . xiii
Preface . . . xvii
Part I Key drivers for waste management and co-product recovery in food processing 1 Waste minimization, management and co-product recovery in food processing: an introduction . . . 3
K. Waldron, Institute of Food Research, UK 1.1 Introduction: food processing waste – the scale of the problem . . . 3
1.2 Diversifi cation and risk . . . 5
1.3 Biological basis of biowastes . . . 7
1.4 Legislation . . . 8
1.5 Implementation of the waste hierarchy concept in relation to food processing co-products and wastes . . . . 15
1.6 High-value components and whole-waste exploitation . . . 17
1.7 Future trends . . . 18
1.8 Sources of further information and advice . . . 19
1.9 References . . . 19
2 Consumer interests in food processing waste management
and co-product recovery . . . 21
L. J. Frewer and B. Gremmen, Wageningen University, The Netherlands 2.1 Introduction: consumer interests as a key driver to improve waste management in food processing . . . 21
2.2 Societal issues related to sustainability . . . 23
2.3 Implications for food processors . . . 31
2.4 Future trends . . . 33
2.5 References . . . 33
Part II Optimising manufacturing to minimise waste in food processing 3 Chain management issues and good housekeeping procedures to minimise food processing waste . . . 39
R. Sherman, North Carolina State University, USA 3.1 Introduction . . . 39
3.2 Key reasons to minimise waste . . . 40
3.3 Chain management to minimise waste . . . 42
3.4 Good housekeeping procedures to minimise raw material waste . . . 43
3.5 Effective implementation of measures to minimise waste . . . 51
3.6 Case study . . . 53
3.7 Future trends . . . 55
3.8 Sources of further information and advice . . . 56
3.9 Further reading . . . 57
3.10 References . . . 58
4 Process optimisation to minimise energy use in food processing . . . 59
Jirˇi Klemeš and Simon J. Perry, The University of Manchester, UK 4.1 Introduction: energy use in food processing . . . 59
4.2 Energy saving and minimisation: process integration/ pinch technology, combined heat and power minimisation and combined energy and water minimisation . . . 61
4.3 Renewables in the food industry . . . 69
4.4 Overview of selected case studies . . . 70
4.5 A case study: sugar processing . . . 72
4.6 Further studies . . . 77
4.7 Sources of further information and advice . . . 81
4.8 References . . . 87
5 Process optimisation to minimise water use in food
processing . . . 90
Jirˇi Klemeš and Simon J. Perry, The University of Manchester, UK 5.1 Introduction: water use and wastage in food processing . . . 90
5.2 How to minimise water usage and wastewater treatment – present state-of-the-art and future trends . . . 93
5.3 Overview of selected case studies . . . 100
5.4 Sources of further information and advice . . . 110
5.5 References . . . 113
Part III Key issues and technologies for food waste separation and co-product recovery 6 The importance of microbiological risk management in the stabilisation of food processing co-products . . . 119
T. F. Brocklehurst, Institute of Food Research, UK 6.1 Introduction: importance of microbiological risk management in the stabilisation of co-products . . . 119
6.2 Strategies for microbiological risk management . . . 120
6.3 Strategies for controlling micro-organisms: methods of preservation . . . 127
6.4 Future trends . . . 143
6.5 References . . . 145
7 Effects of postharvest changes in quality on the stability of plant co-products . . . 149
M. E. Saltveit, University of California, USA 7.1 Introduction . . . 149
7.2 Changes during fruit ripening . . . 150
7.3 Response to adverse environments . . . 155
7.4 Changes in composition . . . 160
7.5 Future trends . . . 162
7.6 Sources of further information and advice . . . 163
7.7 Reference . . . 164
8 The potential for destructuring of food processing waste by combination processing . . . 165
A. C. Smith, Institute of Food Research, UK 8.1 Introduction. . . 165
8.2 Effect of destructuring on foods and their components . . . 167
8.3 Lessons from other industries . . . 175
8.4 Preservation processes . . . 176
8.5 Tools for breakdown/disassembly . . . 179
8.6 Processes . . . 182
8.7 Examples of combination processing . . . 189
8.8 Future trends . . . 191
8.9 Sources of further information and advice . . . 192
8.10 References . . . 192
9 Enzymatic extraction and fermentation for the recovery of food processing products . . . 198
K. Bélafi -Bakó, University of Veszprém, Hungary 9.1 Introduction and key issues . . . 198
9.2 Biocatalytic methods . . . 199
9.3 Future trends . . . 210
9.4 Sources of further information and advice . . . 211
9.5 References . . . 211
10 Supercritical fl uid extraction and other technologies for extraction of high-value food processing co-products . . . 217
T. H. Walker, P. Patel and K. Cantrell, Clemson University, USA 10.1 Introduction . . . 217
10.2 Key reasons for use of supercritical fl uid extraction (SFE) . . . 220
10.3 Supercritical fl uid extraction . . . 220
10.4 Modeling of solubility and mass transfer . . . 232
10.5 Other technologies . . . 242
10.6 Future trends . . . 245
10.7 Acknowledgements . . . 246
10.8 References . . . 246
11 Membrane and fi ltration technologies and the separation and recovery of food processing waste . . . 258
B. Ditgens, University of Bonn, Germany 11.1 Introduction . . . 258
11.2 Established membrane technologies . . . 260
11.3 New fi elds of application . . . 267
11.4 Conclusions . . . 277
11.5 Notation . . . 278
11.6 References . . . 278
12 Separation technologies for food wastewater treatment and product recovery . . . 282
H. M. El-Mashad and R. Zhang, University of California, USA 12.1 Introduction . . . 282
12.2 Principles for separation . . . 283
12.3 Separation and recovery technologies . . . 283
12.4 Future trends . . . 297
12.5 Conclusions . . . 298
12.6 Sources of further information and advice . . . 298
12.7 References . . . 299
Part IV Waste management in particular food industry sectors and recovery of specifi c co-products 13 Waste management and co-product recovery in red and white meat processing . . . 305
P. Roupas, K. De Silva and G. Smithers, CSIRO-Food Science Australia, Australia; and A. Ferguson, Alamanda Enterprises Pty Ltd, Australia 13.1 Introduction . . . 305
13.2 Waste minimization and processing effi ciency. . . 306
13.3 Responsible waste disposal . . . 308
13.4 Waste value-addition . . . 314
13.5 Conclusions and future trends . . . 326
13.6 Sources of further information and advice . . . 327
13.7 References . . . 328
14 Waste management and co-product recovery in dairy processing . . . 332
R. J. Durham and J. A. Hourigan, University of Western Sydney, Australia 14.1 Introduction . . . 332
14.2 Worldwide dairy production trends . . . 333
14.3 Current status of waste problems faced by the dairy industry . . . 337
14.4 Cleaner production in the dairy industry . . . 347
14.5 Co-product recovery in dairy processing . . . 349
14.6 Improving end-waste management in dairy processing . . . 369
14.7 Future trends . . . 376
14.8 Sources of further information and advice . . . 376
14.9 References . . . 377
15 Waste management and co-product recovery in fi sh processing . . . 388
S. Goldhor, Center for Applied Regional Studies, USA, and J. Regenstein, Cornell University, USA 15.1 Introduction . . . 388
15.2 Co-product recovery and development . . . 388
15.3 Shellfi sh . . . 410
15.4 Future trends . . . 413
15.5 Sources of further information and advice . . . 414
15.6 References . . . 415
16 Recovery and reuse of trimmings and pulps from fruit and vegetable processing . . . 417
M. Panouillé, M.-C. Ralet, E. Bonnin and J.-F. Thibault, Institut National de la Recherche Agronomique, France 16.1 Introduction . . . 417
16.2 Origin and general characterisation of the by-products . . . 418
16.3 Use of the whole by-products . . . 421
16.4 Recovery of functional biopolymers . . . 423
16.5 Upgrading of the mono-/oligomeric components . . . 431
16.6 Conclusion and future trends . . . 438
16.7 Sources of further information and advice . . . 439
16.8 References . . . 439
17 High-value co-products from plant foods: nutraceuticals, micronutrients and functional ingredients . . . 448
F. A. Tomás Barberán, CEBAS (CSIC), Spain 17.1 Introduction . . . 448
17.2 Residues generation and key reasons for co-product recovery . . . 449
17.3 Phytochemicals present in plant food residues . . . 450
17.4 Uses of plant food residues as sources for phytochemical extracts . . . 453
17.5 Important sources of high-value co-products . . . 455
17.6 Examples of phytochemical extracts from plant food wastes . . . 462
17.7 Technological processes for phytochemicals extraction from residues . . . 463
17.8 Safety issues . . . 465
17.9 Future trends . . . 465
17.10 Conclusions . . . 465
17.11 References . . . 466
18 High-value co-products from plant foods: cosmetics and pharmaceuticals . . . 470
A. Femenia, Universitat de les Illes Balears, Spain 18.1 Introduction . . . 470
18.2 Key reasons for exploiting plant-derived compounds from co-products . . . 472
18.3 Recovery of plant-based co-products for use in
cosmetics and pharmaceuticals . . . 474
18.4 Future trends . . . 489
18.5 Sources of further information and advice . . . 490
18.6 References . . . 491
19 Natural dyes from food processing wastes . . . 502
T. Bechtold A. Mahmud-Ali and R. Mussak, University of Innsbruck, Austria 19.1 Introduction . . . 502
19.2 Natural dyes in technical textile dyeing operations . . . . 502
19.3 The extraction step . . . 512
19.4 Sources for natural dyes – results of a screening for sources in food processing . . . 514
19.5 Natural dyes from food processing wastes – representative examples . . . 517
19.6 Future trends . . . 529
19.7 Sources of further information and advice . . . 530
19.8 References . . . 530
20 Improving waste management and co-product recovery in vegetable oil processing . . . 534
M. Arienzo and P. Violante, Università degli Studi di Napoli Federico II, Italy 20.1 Introduction . . . 534
20.2 Key reasons to improve waste management in vegetable oil processing . . . 539
20.3 Co-product recovery in vegetable oil processing . . . 542
20.4 Reducing waste in vegetable oil production . . . 554
20.5 Improving end waste management in vegetable oil production . . . 556
20.6 Future trends . . . 565
20.7 References . . . 566
Part V Minimising disposal: wastewater and solid waste management in the food industry 21 Treatment of food processing wastewater . . . 573
D. Bolzonella and F. Cecchi, University of Verona, Italy, and P. Pavan, Cà Foscari University, Italy 21.1 Introduction . . . 573
21.2 Food wastewater production and characteristics . . . 574
21.3 Analysis of conventional technologies for treatment of food processing wastewater . . . 578
21.4 Future trends . . . 587
21.5 References . . . 592
22 Dewatering systems for solid food processing waste . . . 597
V. Orsat and G. S. Vijaya Raghavan, McGill University, Canada 22.1 Introduction . . . 597
22.2 Waste conditioning . . . 598
22.3 Dewatering methods . . . 598
22.4 Combining dewatering methods . . . 605
22.5 An environmental and economic choice . . . 606
22.6 Conclusions . . . 607
22.7 References . . . 607
23 Fermentation, biogas and biohydrogen production from solid food processing . . . 611
C. L. Hansen and D. Y. Cheong, Utah State University, USA 23.1 Introduction: fermentation, biogas and biohydrogen production from food waste . . . 611
23.2 Key reasons to consider using anaerobic processes . . . . 612
23.3 Biochemical and microbiological principles of the anaerobic process: hydrolysis, acidogenesis, methanogenesis . . . 615
23.4 Environmental and operational variables of anaerobic treatment . . . 617
23.5 High-rate anaerobic bioconversion system . . . 624
23.6 Requirements for high-rate anaerobic bioconversion systems . . . 624
23.7 Single-stage high-rate anaerobic digesters . . . 625
23.8 Continuously stirred tank reactor (CSTR) . . . 630
23.9 Separation of anaerobic processes in reactor systems . . . 630
23.10 Biohydrogen production by anaerobic fermentation . . . 632
23.11 Producing other chemicals and useful products from food waste . . . 637
23.12 Future trends . . . 640
23.13 References . . . 642
Index . . . 649
(* = main contact) Editor and Chapter 1 Dr Keith W. Waldron Institute of Food Research Norwich Research Park Colney
Norwich NR4 7UA UK
email: keith.waldron@bbsrc.ac.uk Chapter 2
Professor Lynn Frewer and Dr Bart Gremmen
Gewoon Hoogleraar
WU Maatschappijwetenschappen Hollandseweg 1
6706KN Wageningen 5022
The Netherlands
email: lynn.frewer@wur.nl bart.gremmen@wur.nl
Chapter 3
Professor Rhonda L. Sherman Extension Solid Waste Specialist NC State University
Biol. & Agri. Engineering Raleigh
NC 27695 USA
email: rhonda_sherman@ncsu.edu Chapters 4 and 5
Dr Jirˇi Klemeš and Simon John Perry
Centre for Process Integration CEAS
The University of Manchester PO Box 88
Manchester M60 1QD UK
email: Jiri.klemes@umist.ac.uk
Chapter 6
Professor Tim F. Brocklehurst Head of Microbial Biophysics Group
Institute of Food Research Norwich Research Park Colney
Norwich NR4 7UA UK
email: Tim.Brocklehurst@bbsrc.
ac.uk Chapter 7
Professor Mikal E. Saltveit Mann Laboratory
Department of Plant Sciences University of California One Shields Avenue Davis
CA 95616-863 USA
email: mesaltveit@ucdavis.edu Chapter 8
Dr Andrew C. Smith Institute of Food Research Norwich Research Park Colney
Norwich NR4 7UA UK
email: andrew.smith@bbsrc.ac.uk
Chapter 9
Dr Katalin Bélafi -Bakó University of Veszprém
Research Institute of Chemical and Process Engineering Veszprém 8200
Egyetem u. 2.
Hungary
email: bako@mukki.richem.hu Chapter 10
Terry H. Walker*, Paresh Patel and Keri Cantrell
Biosystems Engineering Clemson University 225 McAdams Hall Clemson
SC 29634 USA
email: walker4@CLEMSON.EDU Chapter 11
Dr Birgit Ditgens
Institut für Ernährungs- und Lebensmittelwissenschaften Bereich Lebensmitteltechnologie und -mikrobiologie
Universität Bonn Römerstraße 164 D-53117 Bonn Germany
email: b.ditgens@uni-bonn.de
Chapter 12
Ruihong Zhang* and Hamed M. El-Mashad
Department of Biological and Agricultural Engineering University of California One Shields Avenue Davis
CA 95616 USA
email: rhzhang@ucdavis.edu Chapter 13
Dr Geoffrey W. Smithers*, Peter Roupas and Kirthi De Silva CSIRO-Food Science Australia 671 Sneydes Road (Private Bag 16) Werribee
Melbourne Victoria 3030 Australia
email: geoff.smithers@csiro.au Alan Ferguson
Alamanda Pty Ltd 77 Temple Street Coorparoo Brisbane
Queensland 4151 Australia
Chapter 14
Dr Rosalie J. Durham* and J. A. Hourigan
Centre for Plant & Food Science University of Western Sydney, Hawkesbury Campus
Locked Bag 1797 South Penrith
New South Wales 1797 Australia
email: r.durham@uws.edu.au
Chapter 15
Dr Susan Goldhor*
Center for Applied Regional Studies 45-B Museum Street
Cambridge MA 02138-1921 USA
email: susangoldhor@comcast.net Professor Joe M. Regenstein Dept. of Food Science Stocking Hall
Cornell University Ithaca, NY 14853-7201 USA
email: jmr9@cornell.edu Chapter 16
Maud Panouillé, Marie-Christine Ralet, Estelle Bonnin* and Jean-François Thibault
Institut National de la Recherche Agronomique
Unité de Recherche Biopolymères, Interactions, Assemblages
Rue de la Géraudière B.P. 71627-44316 Nantes Cedex 03 France
email: bonnin@nantes.inra.fr Chapter 17
Francisco A. Tomás-Barberán CEBAS (CSIC)
P.O. Box 164 Espinardo (Murcia) 30100
Spain
email: fatomas@cebas.csic.es
Chapter 18 Antoni Femenia
Departament de Química Universitat de les Illes Balears Ctra Valldemossa km 7.5 07122 Palma de Mallorca Spain
email: antoni.femenia@uib.es Chapter 19
Thomas Bechtold*, Amalid Mahmud-Ali and Rita Mussak Institute for Textile Chemistry and Textile Physics
University of Innsbruck Hoechsterstrasse 73 A-6850 Dornbirn Austria
email: textilchemie@uibk.ac.at Chapter 20
Professor Michele Arienzo* and Professor Pietro Violante
Dipartimento di Scienze del Suolo della Pianta e dell’Ambiente Via Università 100
80055 Portici Italy
email: michele.arienzo@unina.it Chapter 21
David Bolzonella and Professor Franco Cecchi*
Department of Science and Technology
University of Verona Strada Le Grazie 15 37134
Verona Italy
email: franco.cecchi@univr.it
Paolo Pavan
Department of Environmental Sciences
Cà Foscari University Dorsoduro 2137 30123 Venice Italy
Chapter 22
Valérie Orsat* and G. S. Vijaya Raghavan
Bioresource Engineering Department
McGill University Ste-Anne de Bellevue Quebec
H9X 3V9 Canada
email: valerie.orsat@mcgill.ca Chapter 23
Professor Conly L. Hansen Nutrition and Food Sciences Department
Room 242
Utah State University 8700 Old Main Hill Logan
UT 84322-8700 USA
email: chansen@cc.usu.edu
The global intensifi cation of agriculture and food production has led to the creation of vast quantities of food co-products and wastes, often in central- ised locations as food processors seek to achieve economies of scale.
Typically, the food industry produces considerable amounts of biodegrad- able wastes, including large volumes of effl uent and residues with a high biological oxygen demand (BOD) and chemical oxygen demand (COD) content. Their uncontrolled spoilage and decomposition lead to the produc- tion of methane and other toxic moieties that are environmentally hazard- ous. In Europe alone, over 220 million tonnes of food-related waste are disposed of annually.
As a consequence of increased environmental awareness, the food industry is facing mounting pressures to reduce food processing and related wastes, for example in the form of legislation such as the EU Council Directive 1999/31/EC on the landfi ll of waste. Such pressures have con- tributed to an increase in costs of disposal and a reduction in landfi ll availability in many member states. Hence, methods to (a) reduce waste production, (b) valorize unused co-products, and (c) improve the manage- ment of unavoidable wastes, are becoming increasingly important to the food industry. Coincidentally, there is an increasing body of scientifi c lit- erature relevant to exploiting food processing co-products. However, much of it is published in journals that do not focus specifi cally on this topic. This makes it more diffi cult for food technologists and industrialists to evaluate the ‘state-of-the-art’, and to exploit knowledge and expertise currently available.
It is in this context that the Handbook of waste management and co- product recovery in food processing has been conceived. The current volume
comprises contributions from an array of internationally recognized experts who have reviewed the latest developments in this area, with special refer- ence to optimizing manufacturing processes to decrease waste, understand- ing how to reduce energy and water loss, and methods that may be used to valorize co-products.
The book provides expert opinion on topics relevant to the minimization of waste, and maximization of co-product recovery in food processing.
There are fi ve parts:
Part I Key drivers for waste management and co-product recovery in food processing
This section provides an introduction to the subject, with special reference to the principal drivers. These include legislative pressures (Chapter 1) and the interests of the consumer (Chapter 2).
Part II Optimizing manufacturing to minimize waste in food processing This section focuses on the minimization of waste, both in terms of biowaste and effi cient energy management. Chapter 3 highlights the importance of chain management and good housekeeping practices. Such management is important in reducing instances of irregular waste production that arise from managerial and technical problems. The waste is usually ‘one-off’ in nature, and hence is diffi cult to upgrade because of the absence of a regular co-product, thus negating any opportunities for economies of scale. This chapter also emphasizes chain management from an environmental and life-cycle analysis perspective. Chapter 4 explores the potential for minimi- zation of energy use in food processing, highlighting the energy-intensive nature of the industry. For example, a typical energy requirement for the delivery of 1 J in the form of food consumes almost 10 J from natural resources. Chapter 5 completes Part II by evaluating opportunities to mini- mize water use and wastage. Such activities have the concomitant knock- on effect of reducing the effl uent production, thereby reducing the requirement for additional treatment.
Part III Key issues and technologies for food waste separation and co-product recovery
This is a broad section bringing together expert opinion on research and technology associated with stabilization, fractionation, extraction and fi ltration of waste streams. Chapter 6 focuses on the microbiological stabi- lization of food processing waste which is fundamental to retaining food- grade quality characteristics and ensuring that maximum value can be obtained from subsequent processing activities. The chapter introduces the importance of HACCP development, not only before and during stabilization but during subsequent exploitation. Chapter 7 extends the concept of stabilization by considering the autolytic and natural deteriora-
tion of waste materials of biological origin once they have been damaged or taken out of their natural environment. Chapter 8 provides a general overview of combination processes that may be used in disassembling co- products – taking into account their structural, chemical and biochemical heterogeneity – whilst Chapter 9 looks at the use of biochemical routes for extraction and waste exploitation. This is followed by an evaluation of modern separation technologies. Chapter 10 explores supercritical CO2 methods whilst Chapter 11 highlights the emerging and rapidly growing arena of membrane fi ltration technologies. This part is then completed by Chapter 12 on separation technologies used for food wastewater treatment, with special reference to the recovery of valuable products and water recycling.
Part IV Waste management in particular food industry sectors and recovery of specifi c co-products
The aim of this section is to provide specifi c examples of waste management in the main food processing sectors of meat-, fi sh- and plant-derived co- products. Chapter 13 provides a comprehensive account of waste manage- ment and co-product recovery in red and white meat processing, highlighting the diffi culties encountered during the past decade due to legislation and food safety concerns. Chapter 14 focuses on dairy processing, an arena that has demonstrated huge improvements in effi ciencies during the past 20 years; Chapter 15 gives a general overview of waste management and co- product recovery in fi sh processing. The remaining chapters in this section relate to the exploitation of plant-based wastes: Chapter 16 reviews the recovery and exploitation of trimmings and pulps from fruit and vegetable processing with emphasis on cell-wall polymer exploitation; Chapter 17 focuses on the extraction and exploitation of intracellular phytochemicals, revealing their potential for use in functional foods and pharmaceuticals.
Chapter 18 takes this concept further by extending it into the cosmetics and pharmaceuticals arena. Chapter 19 explores the non-food exploitation of phytochemicals in relation to the production of natural dyes from food processing wastes, and Chapter 20 completes Part 4 by considering the problems of waste and co-product exploitation in the vegetable oil processing industry.
Part V Minimizing disposal: wastewater and solid waste management in the food industry
The fi nal part of the book considers research and development and technologies relevant to the disposal of food processing wastes. Chapter 21 explores the treatment of wastewater generally with emphasis on general macro pollutants, COD, BOD, suspended solids, etc., and introduces anaerobic and aerobic treatments. Chapter 22 evaluates the technologies available for dewatering solid food processing waste streams, including
the use of modern electric fi eld enhancement; Chapter 23 takes the anaerobic concept further by looking at the potential for generating a return on the waste through energy recovery in the form of biohydrogen production.
Keith Waldron
Key drivers for waste management and
co-product recovery in food processing
Waste minimization, management and co-product recovery in food processing:
an introduction
K. Waldron, Institute of Food Research, UK
1.1 Introduction: food processing waste – the scale of the problem
The global food and drink industry is one of the largest industry sectors and is essential to all economies. This refl ects its role in contributing to the basic needs and requirements of every living person (Maslow, 1970).
Consequently, the last 50 years has witnessed an immense increase in the demand for food due to the rapid growth in world population (Fig. 1.1) and the associated increase in wealth. The response to these drivers has been an intensifi cation of agriculture, food production, transport and storage. Values for global food production are substantial. Annually, meat production is in the order of 200 million tonnes; dairy milk production is about 514 million tonnes, cereal production (including rice, wheat and coarse grains) is approximately 2 billion tonnes (OECD, 2004). In money- rich but time-poor ‘developed countries’, the increased consumption of food has been accompanied by the explosive growth in food processing, with particular emphasis on the development of energy-intensive, ready-to- heat/eat canned, frozen, dried and fresh meals. As globalization increases across all sectors, such processing is now being carried out throughout the world, and many fi nal products are then transported to appropriate markets.
Food processing creates waste. Of approximately 3 billion tonnes of waste generated each year in Europe it has been estimated that the member states produce in the region of 222 million tonnes of food waste and by-products across the key sectors (AWARENET, 2004; Fig. 1.2). A
Fig. 1.1 Estimated previous and projected growth of the global human population (Source: Various).
Fig. 1.2 European food waste across the different sectors (AWARENET, 2004).
0 1 2 3 4 5 6 7 8 9 10
1940 1960 1980 2000 2020 2040 2060
Year
Population (billion)
2006
0 20 40 60 80 100 120 140 160
Meat Fish Milk Vegetables
and fruit
Wine
Sectors
Millions of tonnes
signifi cant proportion of this is exploited (valorized) to some extent, for example as a substrate for animal feed. However, large quantities of material are disposed of by landfi ll and other environmentally sensitive routes.
There are a number of reasons why so much food processing waste is produced, some economic and some technological. Traditional methods of food preparation result in relatively small amounts of locally produced domestic waste which, in the past, would have been disposed of as feed, by composting or through municipal waste disposal.
However, industrial food processing, particularly that associated with the production of ready-to-eat meals, has created large, geographically localized waste streams which have generally increased over time as fi rms have sought to benefi t from economies of scale. Furthermore, the majority of food processing systems were developed at least 20–30 (or more) years ago when waste disposal – particularly in the vegetable, cereal and fruit processing industries – was not the issue it is today. The amounts of waste, as a proportion of the raw material, are shown in Fig. 1.3. In the past, the value added by processing a portion of a raw food material to create a high-priced product outweighed the costs of disposal and, for many processes, there was little incentive to fi nd alter- native means to deal with the waste streams. Indeed, from a strategic viewpoint, such an approach would involve signifi cant business risk (see Section 1.2 below). As a result, the development of technologies and approaches for exploiting waste streams was not such a priority; waste production remained integral to the development of food processing systems.
1.2 Diversifi cation and risk
The diffi culty of exploiting food processing waste may be considered from a business management perspective. Because of the specifi city of a given raw material and its processing in relation to a particular product, surplus and waste food processing co-products are not readily utilized by the parent processors. Exploitation of the waste would necessitate a degree of diversifi cation which would probably include the formulation of new products for current or new markets. This would create a high degree of risk (Ansoff, 1957; Fig. 1.4), which is not attractive to food industry players, especially since the industry is in a mature state, and the products are mostly commodities. It is not surprising that processors generally prefer their waste streams to be removed from their premises by third parties. The diffi culties of dealing with wastes are compounded by the rapid deterioration of biological materials due to autolytic, chem- ical and microbial spoilage, resulting in a loss of food-grade potential and
Handbook of waste management and co-product recovery
Fig. 1.3 Indication of the quantity of non-utilized raw material (light grey, minimum amount; dark grey, maximum amount) (AWARENET, 2004).
0 10 20 30 40 50 60 70 80 90 100
Fish canning Fish filleting, curing, salting, smoking Crustaceans processing Molluscs processing Beef slaughtering Pig slaughtering Poultry slaughtering Milk, butter and cream production Yoghurt production Fresh, soft and cooked cheese White wine production Red wine production Fruit and vegetables juice production Fruit and vegetables processing Vegetable oil production Corn starch production Potato starch production Wheat starch production Sugar production from sugar beet
Percentage non-utilized raw material
PROCESS
associated value. Such materials would be fi t only for non-food applications, or disposal.
1.3 Biological basis of biowastes
Food processing waste is derived from the processing of biological materials and is, in the main, biodegradable. Biowaste is defi ned in the landfi ll directive as ‘waste capable of undergoing anaerobic or aerobic decomposition such as food and garden waste, and paper and cardboard’. The waste may be derived from plant, animal, fungal and bacterial sources, with the plant and animal origins predominating. A list of key production processes that create waste streams has been identifi ed in the AWARENET handbook (2004; see also Fig. 1.3). A variety of waste streams will be created by the different stages of each process; these have also been described generically (AWARENET, 2004). Biological wastes are highly complex since they have been derived from highly intricate living organisms and can range from whole, unused (rejected) materials through to fractions and mixtures produced by physical, thermal, chemical and biochemical processing of the original raw material. Plant wastes include vegetable and fruit trimmings (comprising whole/partial organs and tissues) and cereal residues such as bran and extracted barley grain through to pulps and residues remaining after oil, starch, sugar and juice extraction. Animal-derived processing
Fig. 1.4 Ansoff’s matrix (after Ansoff, 1957).
Markets
Products
Current New
Market penetration / consolidation
Product development
Market
development DIVERSIFICATION
CurrentNew
wastes include blood, bone and neural tissues along with wastes from dairy processing. In addition, large quantities of wastewater are often produced. More complex mixed wastes are often produced in the pro- duction of ready meals which are composed of both animal and plant material. Hence, food processing wastes are heterogeneous in their composition due to the impact of the varied processing activities on the complex raw materials.
1.4 Legislation
This section provides a general and historical overview of some of the legislation relevant to the disposal or exploitation of food processing co- pro ducts. It is not defi nitive, and any formal advice and up-to-date informa- tion on legislative requirements should be sought from alternative and accredited sources.
1.4.1 Overview
Food wastes and effl uents are rich in biodegradable components with high biological oxygen demand (BOD) and chemical oxygen demand (COD) content. If they are unmanaged and untreated, their uncontrolled decomposition is hazardous to the environment due to the production of methane and toxic materials (Waldron et al., 2004). In order to reduce the impact of waste, a range of waste management strategies have been adopted at national and international levels. In the European Community (EC), a Community Strategy for Waste Management (see Sanders and Crosby, 2004) was published in 1989 and amended in 1996 (COM(96)0339) setting out key legal principles, including: (1) the prevention principle – to limit waste production; (2) the polluter pays principle – i.e. the polluter should pay for dealing with the waste; (3) the precautionary principle – waste problems should be predicted; (4) the proximity principle – as far as it is possible to do so, waste problems should be addressed near or at the place of production. These principles were created to form the framework of European waste policy. Sanders and Crosby (2004) have also highlighted three particular areas of importance within the strategy: (1) a waste management hierarchy (Fig. 1.5; AWARENET, 2004; DEFRA 1) in which priority should be given to the prevention and recovery of waste, and the optimization and minimization of disposal (often referred to as the ‘3 “R”s’ ‘reduce, reuse and recycle’); (2) producer responsibility whereby producers must take back end-of-life products; (3) control of waste shipments, with references to importing and exporting of waste within European Union (EU) countries.
Fig. 1.5 The waste hierarchy.
Waste prevention
Re-use
Recycle/compost Energy recovery Disposal
Preference Preference
In the EU, legislation comprises directives (to be implemented through the national legislation of member states) and regulations (directly applicable). In the United Kingdom (UK), information on implementation of EU directives via UK Government legislation may be found on the DEFRA website (DEFRA 2), and related links. In 1975, the EU introduced the Waste Framework Directive (WFD) (75/442/EEC) which was later modifi ed by Directive 91/156/EEC to take into account the principles from the Community Strategy for Waste Management (1989 above). The overall regulatory and legislative arena concerning ‘waste’ covers a very broad range of materials and industrial sectors. Therefore it is appropriate to highlight the main legislation relevant to food industry waste as highlighted by AWARENET.
These include:
1 Council Directive 96/61/EC on Integrated Pollution Prevention and Control – which seeks to prevent/reduce/eliminate pollution at source;
2 Council Directive 1999/31/EC on Landfi ll – which sets national targets for reduction of landfi ll of biodegradable municipal waste;
3 Regulation 1774/2002 on health rules regarding animal by-products not fi t for human consumption;
4 Council Directive 2000/76/EC on incineration – to limit negative effects on the environment and human health.
At the time of the AWARENET report, a future directive on biowaste was foreseen prior to the end of 2004. However, this does not appear to have
materialized. Indications are that biowaste will be dealt with under the auspices of other legislative activites. Further information on EU legislation may be found in Table 1.1. Details of the legislation content may be found on the Europa websites (Europa, 2006). A more comprehensive overview of legislation (as of 2004) may be found in Sanders and Crosby (2004) and AWARENET (2004). A general history of waste legislation in the EU may be found on the EU Environmental Information and Legislation Database (see Section 1.9).
1.4.2 Defi nition of waste
The defi nition of waste has been surprisingly diffi cult to agree on.
The Organisation for Economic Co-operation and Development (OECD), the Secretariat of the Basel Convention and the EU Commission each has formally its own defi nition of waste, and information on these can be found on the website of the European Topic Centre on Resource and Waste Management (2006). According to this source, the ‘most
Table 1.1 Relevant EU legislation; see AWARENET (2004) and Sanders and Crosby (2004) for further details
Legislation on solid and liquid wastes
Council Directive 75/439/EEC on the disposal of waste oils Council Directive 75/442/EEC on waste
Council Directive 76/464/EEC on pollution caused by certain dangerous substances discharged into the aquatic environment of the Community Council Directive 80/68/EEC on measures and restrictions for the protection
of groundwater against pollution caused by certain dangerous substances Waste Framework Directive 91/156/EEC
Council Directive 91/271/EEC concerning urban wastewater treatment Council Directive 91/689/EEC on hazardous waste
Council Regulation 259/93 on the supervision and control of shipments of waste
Council Directive 94/67/EEC on the incineration of hazardous waste Commission Decision 96/350/EC for the adaptation of Annex IIA and IIB
of Directive 75/442 EEC on waste
Council Directive 1999/31/EC on the landfi ll of waste
Commission Decision 2000/532/EC establishing a list of wastes Water Framework Directive 2000/60/EC
Council Directive 2000/76/EC on the incineration of waste Regulation 2150/2002/EC on waste statistics
Council Decision 2003/33/EC on criteria for acceptance of waste at landfi lls Legislation concerning added-value products from food wastes
Regulation 1774/2002/EC on health rules concerning animal by-products not intended for human consumption
Directive 2003/30/EC on the promotion of the use of biofuels or other renewable fuels for transport
Table 1.1 cont’d
Council Directive 79/373/EEC on the marketing of compound feedingstuffs Council Directive 90/667/EEC on veterinary rules for the disposal and processing
of animal waste
Council Directive 95/53/EC concerning the organization of offi cial inspections in the fi eld of animal nutrition
Council Decision 1999/534/EC on measures on animal waste protecting against transmissible spongiform encephalopothies (TSE)
Council Decision 2000/7656/EC on protection measures regarding TSE and feeding of animal protein
Decision 2001/25/EC prohibiting the use of certain animal by-products in animal feed
Regulation 999/2001/EC for prevention, control and eradication of TSE
Regulation 811/2003/EC on intra-species recycling ban for fi sh, and burying and burial of animal by-products
Regulation 809/2003/EC on processing standards for category 3 material and manure used in composting plants
Regulation 810/2003/EC on processing standards for category 3 material and manure used in biogas plants
Novel foods
Regulation (EC) No. 258/97 of the European Parliament and of the Council of 27 January 1997 concerning novel foods and novel food ingredients
Commission Decision 2002/150 authorizing the marketing of coagulated potato proteins and hydrolysates as novel food ingredients
Additional specifi c legislation in specifi c agro-food sectors Council Directive 90/496/EEC on nutrition labelling for foodstuffs
Council Regulation 91/493/EC laying down health conditions for production and the placing on the market of fi shery products
Council Directive 94/435/EC on sweeteners for use in foodstuffs Council Directive 94/435/EC on colours for use in foodstuffs
Council Directive 95/2/EC on food additivies other than colours and sweeteners Council Regulation 2200/96/EC on the common organization of the market in
fruit and vegetables
Council Regulation 1493/99/EC on the common organization of the market in wine
Commission Decision 1999/724/EC on specifi c health conditions for hygienic manufacture of gelatine intended for human consumption
Council Regulation 104/2000/EC on the common organization of the markets in fi shery and aquaculture products
Commission Regulation (EC) No. 1623/2000 of 25 July 2000 laying down detailed rules for implementing Regulation (EC) No. 1493/1999 on the common organization of the market in wine with regard to market
Council Directive 2000/13/EC on the approximations of the laws in member states on labeling, presentation and advertising of foodstuffs
Commission Directive 2001/15/EC on substsances that may be added in foods for nutritional purposes
Commission Decision 2001/471/EC on regular checks on health conditions for production and marketing of fresh meat and fresh poultry meat
Council Regulation 178/2002/EC laying down general principles and requirements of food law
explicative’ defi nition of waste may be found in the Joint Questionnaire OECD/Eurostat that is sent biennially to all EU countries and reads as follows:
Waste refers here to materials that are not prime products (i.e. products produced for the market) for which the generator has no further use for their own purpose of production, transformation or consumption, and which he discards, or intends or is required to discard. Wastes may be generated during the extraction of raw materials, during the processing of raw materials to intermediate and fi nal products, during the consumption of fi nal products, and during any other human activity.
Are excluded:
– Residuals directly recycled or reused at the place of generation (i.e. establishment);
– Waste materials that are directly discharged into ambient water or air.
The legal defi nition of waste is provided by the EU Commission in the Waste Framework Directive 75/442/EEC on waste as amended by Council Directive 91/156/EEC, Art.1(a), and is inseparably linked with the EU lists of waste categories and waste types:
‘Waste’ shall mean any substance or object in the categories set out in Annex I which the holder discards or intends or is required to discard.
The Commission has drawn up a list of wastes belonging to the categories listed in Annex I.
Categories of waste from Annex 1 that are relevant to food processing are shown in Table 1.2.
In order to make the defi nition of waste more tangible and to reduce uncertainty, the European Commission has drawn up a list of wastes (Table 1.3; see ‘Waste list’ in reference section). This was established by Commission Decision 2000/532/EC.
Once a material is defi ned as a ‘waste’, it is then subject to a range of directives (e.g. the Waste Framework Directive and the Hazardous Waste Directive) and regulations (e.g. the Waste Shipment Directive) concerning the handling and treatment of waste streams. Therefore, the classifi cation of co- or by-products that are currently disposed of as ‘waste’
is of importance if alternative exploitation routes are to be sought.
Interestingly, there appears to be no legal defi nition of the term ‘co- or by-product’.
A number of issues have arisen in the interpretation of the above waste defi nitions including the meaning of the term ‘discard’ (which lacks a common understanding) compared with ‘dispose’. A number of disputes have required resolution by the European Court of Justice.
The OECD Waste Management Policy Group has produced a guidance document with the aim of clarifying whether or not a material can be
Table 1.2 Categories of waste, Annex 1 of Directive 75/442/EEC Categories of waste
Directive 75/442/EEC, Annex I
Q1 Production or consumption residues not otherwise specifi ed below Q2 Off-specifi cation products
Q3 Products whose date for appropriate use has expired
Q4 Materials spilled, lost or having undergone other mishap, including any materials, equipment, etc. contaminated as a result of the mishap Q5 Materials contaminated or soiled as a result of planned actions (e.g.
residues from cleaning operations, packing materials, containers, etc.) Q6 Unusable parts (e.g. reject batteries, exhausted catalysts, etc.)
Q7 Substances which no longer perform satisfactorily (e.g. contaminated acids, contaminated solvents, exhausted tempering salts, etc.) Q8 Residues of industrial processes (e.g. slags, still bottoms, etc.) Q9 Residues from pollution abatement processes (e.g. scrubber sludges,
baghouse dusts, spent fi lters, etc.)
Q10 Machining/fi nishing residues (e.g. lathe turnings, mill scales, etc.) Q11 Residues from raw materials extraction and processing (e.g. mining
residues, oil fi eld slops, etc.)
Q12 Adulterated materials (e.g. oils contaminated with PCBs, etc.) Q13 Any materials, substances or products whose use has been banned
by law
Q14 Products for which the holder has no further use (e.g. agricultural, household, offi ce, commercial and shop discards, etc.)
Q15 Contaminated materials, substances or products resulting from remedial action with respect to land
Q16 Any materials, substances or products which are not contained in the above categories
regarded as waste. Nevertheless, the situation appears to be less clear at the European level as to the classifi cation of materials that are to be recovered and used as raw materials in other processes (so-called
‘secondary products’) and is made more complicated by interpretations at the member state level. This seems to be an emergent situation, and will be infl uenced further by the development of technologies and approaches to exploit what would previously be regarded as waste material. A fl ow chart depicting the EC legislative relationships between waste, secondary raw material and product is shown in Fig. 1.6 (AWARENET, 2004).
1.4.3 Novel foods legislation
An important piece of legislation which should be considered in the exploitation of food co-products and wastes concerns the regulation on novel foods and novel food ingredients (Regulation (EC) No. 258/97).
Table 1.3 An extract from the EU list of wastes (see ‘Waste list’ in reference section)
02 02 wastes from the preparation and processing of meat, fi sh and other foods of animal origin
02 02 01 sludges from washing and cleaning 02 02 02 animal-tissue waste
02 02 03 materials unsuitable for consumption or processing 02 02 04 sludges from on-site effl uent treatment
02 02 99 wastes not otherwise specifi ed
02 03 wastes from fruit, vegetables, cereals, edible oils, cocoa, coffee, tea and tobacco preparation and processing; conserve production; yeast and yeast extract production, molasses preparation and fermentation
02 03 01 sludges from washing, cleaning, peeling, centrifuging and separation 02 03 02 wastes from preserving agents
02 03 03 wastes from solvent extraction
02 03 04 materials unsuitable for consumption processing 02 03 05 sludges from on-site effl uent treatment
02 03 99 wastes not otherwise specifi ed 02 04 wastes from sugar processing
02 04 01 soil from cleaning and washing beet 02 04 02 off-specifi cation calcium carbonate 02 04 03 sludges from on-site effl uent treatment 02 04 99 wastes not otherwise specifi ed
02 05 wastes from the dairy products industry
02 05 01 materials unsuitable for consumption or processing 02 05 02 sludges from on-site effl uent treatment
02 05 99 wastes not otherwise specifi ed
02 06 wastes from the baking and confectionery industry 02 06 01 materials unsuitable for consumption or processing 02 06 02 wastes from preserving agents
02 06 03 sludges from on-site effl uent treatment 02 06 99 wastes not otherwise specifi ed
02 07 wastes from the production of alcoholic and non-alcoholic beverages (except coffee, tea and cocoa)
02 07 01 wastes from washing, cleaning and mechanical reduction of raw materials
02 07 02 wastes from spirits distillation 02 07 03 wastes from chemical treatment
02 07 04 materials unsuitable for consumption or processing 02 07 05 sludges from on-site effl uent treatment
Some of the components extracted and fractionated from co-products may require evaluation under this legislation. One example of how this might be relevant is given by the Commission Decision 2002/150 regarding the exploitation of potato proteins and hydrolysates as novel ingredients.
1.5 Implementation of the waste hierarchy concept in relation to food processing co-products and wastes
Figure 1.7 shows a simplifi ed diagram of the production of waste materials from the food processing sector and highlights criteria consistent with the waste hierarchy (Fig. 1.5) that need to be addressed in order to minimize disposal requirements. Prevention of waste requires consideration of the Fig. 1.6 Overview of the relationships between waste, secondary raw materials and products, with EC legislation (after AWARENET, 2004). The ‘grey zone’ relates
to an area of dispute between member states.
Waste cycleProduction cycle
End product Intermediary product Coincidental product
Product Primary raw
materials Secondary raw materials
Waste
Grey zone Disposal
Annex II A Recovery
Annex II B
Annexes I, IIA and IIB On-site discard
National/Regional criteria and 91/156/EEC Art.4
National/
Regional criteria and 91/156/EEC Art.4
Note: all of the references in this figure are to articles or annexes of Directive 75/442/EEC as amended by Directive 91/156/EEC
Fig. 1.7 Food processing waste in relation to the waste hierarchy.
Food chain
Raw material
End product
Solid and liquid waste and co-products
Disp osal Processing
activities
Re-use e.g. water Minimization / prevention
•Improved process design
•Improved systems management
Recovery
Additional
products Energy Landfill
Potential exploitation of
food-chain w astes
reasons for its production. For example, waste that results from mistakes in process management – e.g. excess substrates, breakdowns, human error – might be addressed by improved systems management. In contrast, waste that is inherent to the process may have to be addressed by improving the design of the process and is likely to require investment in new plant.
Some wastes, e.g. water, may be recycled if purifi ed effectively, helping in the development of closed-loop factories. Those co-products that are not suitable for recycling may be exploited via the creation of novel products (see below). This approach may be unattractive since it is likely to involve a high-risk strategy on the part of the food processor (see Fig. 1.4).
However, due to the increase in legislative pressures (see above) and consumer demand (see Chapter 2, this volume), this option is becoming increasingly relevant. Some very large co-product streams, e.g. whey from the dairy industry and starch from potato processing, have been success- fully exploited for the production of ingredients for the food sector (Waldron et al., 2004). However, this has taken between 10 and 20 years to occur, refl ecting the time taken for development of new technologies and new markets.
1.6 High-value components and whole-waste exploitation
Many waste streams contain small levels of components that command an apparent and attractive market value. For example, phytochemicals from fruit and vegetable trimmings might be exploited for the production of nutraceuticals, cosmetics or even pharmaceuticals. There has been much interest and research dedicated to exploiting such components with a view to adding value to co-product streams (Waldron, 2004;
Waldron et al., 2004). However, whilst it is often possible, and even rela- tively straight forward in a laboratory to develop a process to extract a ‘high-value’ component, it is frequently uneconomical to do so com- mercially. This may be because the bulk residues remaining after extraction are of lower value, and may actually cost more in disposal.
Therefore, it is important to develop approaches that aim to exploit food co-products in their entirety, ensuring that all components so derived may be of marketable quality. This requires a research and development approach that links all the potential components in the waste stream to the potential markets available. A possible strategy for such an approach is shown in Fig. 1.8 and is based on that which has been proposed in the EU project REPRO (see website). This approach involves exploiting fully traceable, food-grade waste streams. Initially they should be stabilized against microbiological deterioration and autolysis to prevent them from losing their food-grade status. Subsequently they would be disassembled by physical and biochemical approaches (individually and in combination) involving modern enzyme and process- ing technologies. The aim is to provide a range of components, from high value to low value, all of which would contribute to achieving whole-waste exploitation. The process would require evaluation for acceptability, both in relation to safety (via Hazard Analysis Critical Control Point (HACCP) development), novel food legislation, consumer preference and marketing requirements. Such an approach requires close interaction with all stakeholders to maximize knowledge transfer and exploitation.
Finally, some co-products may be unsuitable for exploitation due, for example, to their complexity, uncontrolled spoilage or lack of trace- ability. In such cases, non-food exploitation as energy sources may be appropriate via fermentation and biogas production, and other microbially based disposal systems such as composting. New technologies may provide opportunities to convert such biomass into biofuels. Hence, it should be possible to reduce landfi ll considerably, and in the case of plant-based co-products, to avoid it altogether. Of course, the fi nal arbiter will be the cost-effectiveness of this strategy, as measured by perceived return on investment, and this will have to take into account locally/
