2016 4th edtion food processing technology principles and practice

In countries with a temperate climate, processing ques were developed to preserve food through winter months, including salting andsmoking of meats and fish, fermentation to produce vine

Food Processing Technology

Consultant Food Technologist

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1.5 Quality assurance: management of food quality and safety 90

1.7 Hygienic design and cleaning of processing facilities and equipment 126

4 Size reduction 291

7.8 Other minimal processing methods under development 490

8.1 Sources of heat and methods of application to foods 5158.2 Energy use and methods to reduce energy consumption 518

Part III.A Heat Processing Using Steam or Hot Water 523

14.5 Effects on foods and microorganisms 705

19.3 Infrared heating 838

24.3 Packaging materials for modified atmosphere packaging (MAP) 992

24.5 Packaging developments 1005

For additional information on the topics covered in the book, visit the

companion site:http://booksite.elsevier.com/9780081019078/

Dr Peter Fellows is a senior consultant in food processing, working mostly inAfrica and Asia Over the last 40 years, he has worked extensively as a food tech-nologist in over 20 countries, supporting institutions that promote small-scale agro-industrial development programmes, and identifying opportunities for postharvestprocessing and agro-enterprise development His work includes development ofinformation resources, design of training courses, project and programme mana-gement and evaluation, and consultancies for enterprise support institutions andtertiary educational institutions He has provided support to local production ofready-to-use therapeutic foods in Africa and India to treat children suffering fromsevere-acute malnutrition and he has held the UNESCO Chair in PostharvestTechnology at Makerere University, Uganda Before his consultancy work, he wasHead of Agroprocessing at the international development agency, Practical Action(previously the Intermediate Technology Development Group), where he managedprogrammes in food processing, predominantly in South Asia Prior to this he wassenior lecturer in Food Technology at Oxford Brookes University He graduatedfrom the University of Reading (National College of Food Technology), and afterspending 2 years in Nigeria managing a weaning food production project, hereturned to Reading University to complete his PhD, studying the symbiotic growth

of edible yeasts on fruit processing wastes In addition to the four editions of FoodProcessing Technology, he has written 30 books published by Practical ActionPublications, the Food and Agriculture Organisation of the United Nations, theUnited Nations Industrial Development Organisation, the International LabourOrganisation of the United Nations/TOOL, and the Technical Centre forAgricultural and Rural Cooperation ACP-EU (CTA) He is editor of the journalFood Chain, published by Practical Action and has written
50 papers and articles

on different aspects of food processing He has lived in rural Derbyshire in theUnited Kingdom for over 20 years and is active in researching local history, andcoediting his village newsletter He is part-owner of a shared narrowboat and editor

of the magazine for the National Association of Boat Owners

I am indebted to the large number of people who have given freely of their timeand experience, provided me with information, checked the text and given mesupport during this latest revision of Food Processing Technology My thanks toMariana Kuhl, Editorial Project Manager at Elsevier, for her ideas, suggestions andadministrative support My particular thanks also to the many companies thatresponded positively to my requests for information about their equipment andproducts; some of which went out of their way to share their detailed specialistknowledge Finally, but not least, my special thanks to Wen for her constructivesupport, encouragement and forbearance at my long hours in front of a computerscreen over many months

Peter Fellows

neces-During the ensuing 1000 years, similar food processes developed independently

in many places, with local variations due to differences in climate, crops or foodpreferences Early processes developed in China include tofu (soybean curd),roasted dried millet and dried beef as military rations In Japan, saki (wine) wasproduced from rice, salt made from dried seaweed was used to preserve foods, andsoya was processed to soy sauce and miso (soy paste) to flavour foods In Europe,the first water-powered flour mills and commercial bakeries were developed by theRomans, who also used ice from mountains to refrigerate fruits and vegetables InIndia, the manufacture of sugar from cane had developed in the Indus Valley by

100 BC (Trager, 1995) In countries with a temperate climate, processing ques were developed to preserve food through winter months, including salting andsmoking of meats and fish, fermentation to produce vinegar which was also used topreserve meat and vegetables, and boiling fruits or vegetables to produce jams orchutneys

techni-In the first millennium AD, the comparative isolation of different civilisationsbegan to change, and first travellers and then traders began to exchange ideas andfoods across the world For example in AD 400, the Vandals introduced butter toSouthern Europe, which was used in Northern Europe to replace olive oil By

AD 600, Jewish merchants had established the spice trade with the Orient and by

AD 700, the first written law, which established regulations for the production ofdairy products and preservation of foods, was encoded in China

AD 1000 1800

By the turn of the second millennium, a rapid expansion of trade and exchange offoods and technologies took place by European explorers and military expeditions:for example, in 1148, knights returning from the second Crusade brought sugar toEurope from the Middle East; Marco Polo brought noodles from China; and in the13th century the Mongols spread technologies for making kumiss (fermented mare’smilk), dried cheese and ales made from fermented millet in their invasions ofCentral Asia and Eastern Europe In the 1500s, the Portuguese brought cloves fromthe East Indies for use in preserves and sauces, and to disguise spoiled meat.Spanish conquistadors discovered sun-dried llama, duck and rabbit, which wereeaten uncooked in Peru; and they returned with foods that had never been seenbefore in Europe, including avocado, papaya, tomato, cacao, vanilla, kidney beansand potatoes Originally prepared as a fermented drink in Mesoamerica from

1900 BC, chocolate was served as a bitter, frothy liquid, mixed with spices, wine

or corn pure´e, before its arrival in Europe in the 16th century There it was mixedwith sugar and eventually became the sweet confectionery we know today At thesame time, the Portuguese introduced chilli peppers and cayenne from LatinAmerica to India, where they were used to prepare spiced dishes

As societies developed, specialisation took place and trades evolved, includingmillers, bakers, cheese-makers, brewers and distillers Variations in raw materials

or processing methods gave rise to thousands of distinctive local varieties of breads,cheeses, beers, wines and spirits These were the forerunners of present-day foodindustries, and some foods have been in continuous production for nearly 800 years

by the same communities During this period, mechanical processing equipmentusing water, wind and animal power was developed to reduce the time and labourinvolved in processing; for example, animal-powered mills were used to crusholives for oil in Mediterranean countries and to crush apples for cider in NorthernEurope The Domesday Book of 1086 in England lists nearly 6000 water- andwind-powered flour mills, one for every 400 inhabitants The growth of towns andcities gave impetus to the development of preservation technologies and theextended storage life allowed foods to be transported from rural areas to meet theneeds of urban populations In England, Francis Bacon published his ideas in 1626

on freezing chickens by stuffing them with snow During the 1600s1700s, theslave trade helped change food supplies, eating habits, agriculture and commerce.Ships returning from delivering slaves to Brazil took maize, cassava, sweet potato,peanuts and beans to Africa, where they remain staple foods Cocoa from WestAfrica was brought to Europe and in 1725 the first chocolate company began opera-tion in Britain At this time, in Massachusetts, United States, more than 60 distiller-ies produced rum from molasses that was supplied by slave traders The rumprovided the capital needed to buy African slaves, who were then sold to WestIndian sugar planters A similar circular trade existed in salted cod fish and slavesbetween Britain, America, Africa the Caribbean and Latin America (Kurlansky,

1997, 2002)

The scale of operation by food processing businesses increased during theIndustrial Revolution in the 18th century, but there was an almost total absence ofscientific understanding The processes were still based on craft skills and experi-ence, handed down within families that held the same trades for generations By thelate 1700s, the first scientific discoveries were being made, resulting in chlorinebeing used to purify water and citric acid being used to flavour and preserve foods.

The first ‘new’ food process was developed in France after Napoleon Boneparteoffered a prize of 12,000 Francs to invent a means of preserving food for long peri-ods for military and naval forces Nicholas Appert, a Parisian brewer and pickler,opened the first ‘vacuum bottling factory’ (cannery) in 1804, boiling meat andvegetables and sealing the jars with corks and tar, and he won the prize in 1809.The 19th century saw the pace of scientific understanding increase: Russian chem-ist, Gottlieb Iorchoff, demonstrated that starch breaks down to glucose and a Dutchchemist, Johann Mulder, introduced the word ‘protein’ Technological advances incanning and refrigeration accelerated at an unprecedented rate In 1810, the firstpatent for a tin-plated steel container was issued in Britain, and in 1849 a can-making machine was developed in the United States that enabled two unskilledworkers to make 1500 cans per day, compared to 120 cans per day that could bemade previously by two skilled tinsmiths In 1861 a canner in Baltimore reducedthe average processing time from six hours to 30 minutes by raising the temperature

of boiling water to 121C with calcium chloride; and in 1874, a pressure-cookingretort using steam was invented, leading to rapid expansion of the industry In 1858the first mechanical refrigerator using liquid ammonia was invented in France and

in 1873 the first successful refrigeration compressor was developed in Sweden Thepasteurisation process, named after French chemist and microbiologist LouisPasteur, was developed in 1862 Towards the end of the 19th century, increased sci-entific understanding led the change away from small-scale, craft-based industry,and by the start of the 20th century, the food industry as we now know it wasbecoming established Technological advances gathered speed in all areas of foodtechnology as the century progressed For example, ‘instant’ coffee was invented in

1901, the first patent for hydrogenating fats and oils was issued in 1903, transparent

‘cellophane’ wrapping was patented in France in 1908, the same year that the vour enhancer, monosodium glutamate, was isolated from seaweed In 1923 dex-trose was produced from maize, and widely used in bakery products, beverages andconfectionery In 1929, the merger of Lever Brothers and the Margarine Unionformed the world’s first multinational food company

fla-The introduction of electricity revolutionised the food industry and prompted themanufacture of new specialist food processing machinery For example, in 1918,the Hobart Company in the United States developed the first electric dough mixer,electric food cutters and potato peelers Most food processing at this time supplied

staples (e.g., dried foods, sugar, cooking oil) and processed foods that were used inthe home or in catering establishments (e.g., canned meat and vegetables) Theimpetus for development of some of these foods came from military requirementsduring World War I Later, a ‘luxury’ market developed, which included cannedtropical fruits and ice cream After World War II, a wide range of ready-to-eatmeals, snackfoods and convenience foods began to appear in retail stores Againthese developments had been partly stimulated by the need to preserve foods formilitary rations From the 1950s, food science and technology were taught at uni-versity level, and the scientific underpinning from this and the work of foodresearch institutions created new technologies, products and packaging that resulted

in many thousands of new foods being developed each year

Post-2000: the food industry today

The aims of the food industry today, as in the past, are fourfold:

1 To extend the period during which a food remains wholesome (the shelf-life) by tion techniques that inhibit microbiological or biochemical changes and thus allow timefor distribution, sales and home storage

preserva-2 To increase variety in the diet by providing a range of shapes, tastes, colours, aromas andtextures in foods

3 To provide the nutrients required for health

4 To generate income for the manufacturing company and its shareholders

Each of these aims exists to a greater or lesser extent in all food processing, but

a given product may emphasise some more than others For example, the aim offreezing is to preserve organoleptic and nutritional qualities as close as possible tothe fresh product, but with a shelf-life of several months instead of a few days orweeks In contrast, sugar confectionery and snackfoods are intended to provide vari-ety in the diet by creating a large number of shapes, flavours, colours and texturesfrom basic raw materials All food processing involves a combination of procedures

to achieve the intended changes to the raw materials Each of these ‘unit operations’has a specific, identifiable and predictable effect on a food and the combination andsequence of operations determines the nature of the final product

In many countries, the market for processed foods has changed and consumers

no longer require a shelf-life of several months at ambient temperature for themajority of their foods Changes in family lifestyle and increased ownership ofrefrigerators, freezers and microwave ovens are reflected in demand for foods thatare convenient to prepare, are suitable for frozen or chilled storage, or have a mod-erate shelf-life at ambient temperatures There has also been an increasing demand

by consumers for foods that have a ‘healthy’ or ‘natural’ image and have fewer thetic additives or for foods that have undergone fewer changes during processing.Manufacturers have responded to these pressures by reducing or eliminating syn-thetic colourants from products and substituting them with natural or ‘nature-equiv-alent’ alternatives; and by introducing new ranges of low-fat, sugar-free or low-saltproducts in nearly all subsectors Functional foods, especially foods that contain

syn-probiotic microorganisms and cholesterol-reducing ingredients, have shown a matic increase in demand, and products containing organic ingredients are alsowidely available Consumer pressure has also stimulated improvements to proces-sing methods to reduce damage caused to organoleptic and nutritional properties,and led to the development of a range of novel ‘minimal’ processes, includinghigh-pressure and pulsed electric field processing.

dra-Trends that started during the 1960s1970s, and have accelerated during the last

40 years, have caused food processors to change their operations in four keyrespects: (1) there has been increased investment in capital-intensive equipment toreduce labour and energy costs and to improve product quality; (2) higher invest-ment in computer control of processing operations, warehousing and distributionlogistics to meet more stringent legislative and consumer requirements for traceabil-ity, food safety and quality assurance; (3) high levels of competition and slowergrowth in food markets in industrialised countries has prompted mergers or take-overs of competitors; and (4) a shift in power and control of food markets frommanufacturers to large retail companies

In the 21st century, changes in technology have been influenced by substantialincreases in the costs of both energy and labour, and by public pressure and legisla-tion to reduce negative environmental effects of processing, including ecosystemdegradation, greenhouse gas emissions, loss of biodiversity, overfishing and defor-estation ‘Sustainability’ has become a key concept in food processing (Ohlsson,

2014), which includes reducing the use of resources, energy and waste production(WRI, 2016) Food processing equipment now has increasingly sophisticated levels

of microprocessor control to reduce resource use and processing costs, to enablerapid change-over between shorter production runs, to improve product quality and

to provide improved records for management decisions and traceability Entire cesses, from reception of materials, through processing and packaging to warehous-ing are now automated This has allowed producers to generate increased revenueand market share from products that have higher quality and added value

pro-Although small- and medium-scale food processing businesses are significantcontributors to national economies in many countries, globally some areas of foodprocessing are dominated by a relatively few multinational conglomerates, forexample: five companies control 90% of the international grain trade; two compa-nies dominate sales of half the world’s bananas and three trade 85% of the world’stea; and 30 companies account for a third of the world’s processed food (ActionAid, 2005) During the last 3040 years food companies have formed internationalstrategic alliances that enable them to develop pan-regional economies of scale andenter new markets, especially in South East Asia, India, Eastern Europe and LatinAmerica Global sourcing of raw materials has been a feature of some industriesfrom their inception, but this has expanded to many more sectors to reduce costsand ensure continuity of supply The development of global production and distri-bution (or ‘global value chains’, GVCs) is possible because of developments ininformation and communications technologies, particularly the internet and cloudcomputing These tightly integrated global-scale systems in widely separated loca-tions have reduced the need for highly skilled, highly paid workforces This makes

it possible for companies to move their operations to new countries, often in thedeveloping world, where unskilled and lower-paid workers can be employed Foodproduction is coordinated between distant sites and suppliers can be called upon totransfer goods across the world at short notice These developments have in turnprompted increased consumer awareness of ethical purchasing issues, employmentand working conditions in suppliers’ factories, and the environmental impact ofinternational transportation of foods There has also been a resurgence of consumerinterest in locally distinctive foods and ‘fair-traded’ foods in some countries.Much of the change in global food production and processing has been assisted

by international agreements to remove tariff and nontariff barriers, privatisation andderegulation of national economies to create ‘free’ markets in trade and foreigninvestment The early General Agreements on Tariffs and Trade (GATT) held from

1986 to 1994 expanded the principle of ‘free’ trade in key areas, including ture, where countries were required to reduce subsidies paid to producers andreduce tariffs on imported goods (Hilary, 1999) Agreements related to investmentunder the World Trade Organisation extended the scope of GATT negotiations toinclude services and intellectual property (The General Agreement on Trade inServices), foreign direct investment and copyright, trademarks, patents and indus-trial designs This was facilitated by changes introduced by the InternationalMonetary Fund and World Bank that opened up investment opportunities in manydeveloping countries and helped the creation of GVCs More recently, the Trans-Pacific Partnership has been agreed and there are ongoing negotiations over theTransatlantic Trade and Investment Partnership (TTIP) These are free trade agree-ments that aim to promote trade and multilateral economic growth from increasedmarket access and broader rules, principles and modes of co-operation betweensignatory countries

agricul-References

Action Aid, 2005 Power hungry: six reasons to regulate global food corporations ActionAid Available from: www.nfu.ca/story/power-hungry-six-reasons-regulate-global-food-corporations(www.nfu.ca search ‘Power hungry’) (last accessed February 2016).Hilary J., 1999 Globalisation and Employment Panos Briefing Paper No 33, May, PanosInstitute, London

Kurlansky, M., 1997 Cod: A Biography of the Fish That Changed the World Penguin, NewYork

Kurlansky, M., 2002 Salt: A World History Penguin, New York

Ohlsson, T., 2014 Sustainability and food production In: Motarjemi, Y., Lelieveld, H.(Eds.), Food Safety Management: A Practical Guide for the Food Industry AcademicPress, San Diego, CA, pp 10851098

Trager, J., 1995 The Food Chronology Aurum Press, London

WRI, 2016 Creating a Sustainable Food Future World Resources Report, World ResourcesInstitute Available from:www.wri.org/our-work/topics/food(last accessed February 2016)

About this book

All processed foods have the following stages in their production: (1) raw materialselection, growth and harvest/slaughter; (2) postharvest storage and preprocessing;(3) processing and packaging operations; (4) storage and distribution; and (5) retaildisplay and sale There are three overarching considerations for each of thesestages:

1 Technical considerations, which include: the properties of foods and how these change(due to spoilage or foods becoming unsafe) or can be changed (alteration of eating qualityand/or nutritional value), quality and safety management; engineering considerations such

as the selection of equipment and processing conditions to achieve the required effects onfoods, design and construction of processing facilities

2 Business considerations, including: financial/economic management, food and related regulations, market selection, marketing and advertising, scale of operation andcompetition (e.g., multinational, large, medium, small and micro-scale food businesses),specialist services required at different scales of operation and their availability

food-3 Global considerations: environmental issues and sustainability, value chains and tional trade

interna-Food processing is therefore a multidisciplinary subject that includes chemistry/biochemistry, physics, biology and microbiology, sensory analysis, engineering,marketing, finance and economics, management and psychology

This book focuses mainly on the technical considerations, but where appropriate

it makes reference to some of the business considerations (e.g., food and related regulations) and environmental considerations (e.g., increased sustainability

food-by reductions in the use of resources, energy and pollution) The book aims to duce students of food science and technology or biotechnology to the wide range ofprocessing techniques that are used to process foods It shows how knowledge ofthe properties of foods and the required changes are used to design equipment and

intro-to control processing conditions on an industrial scale The aim is always intro-to makeproducts that are attractive, saleable, safe and nutritious with the required shelf-life

It is a comprehensive yet basic text, offering an overview of most unit operations(Fig I.1), written in straightforward language with the minimum use of jargon andwith explanations of scientific terms and concepts It provides details of the proces-sing methods and equipment, operating conditions and the effects of processing onboth microorganisms that contaminate foods and the physicochemical properties offoods It collates and synthesises information from a wide range of sources, com-bining food processing theory and calculations and results of scientific studies, withdescriptions of commercial practice Where appropriate, references are given torelated topics in food microbiology, nutrition, food engineering, physicochemicalproperties of foods, food analysis, and business operations, including quality assur-ance, marketing, production and logistics management

Blanching (9) Industrial cooking (10) Pasteurisation (11) Sterilisation/UHT (12)

Evaporation &

distillation (13) Extrusion (17) Dehydration (14) Baking (16) Frying (18)

Moisture removal

Smoking (15) Electricity

Centrifugation/

filtration/

membrane separation (3)

Temperature reduction

Freeze drying/

freeze concentration (23)

Chilling (21) Freezing (22)

Direct electrical energy

PEF/ Electric arc (7)

Dielectric/Ohmic (19)

HPP/IR/pulsed light/ UV/ultrasound (7)

Nuclear energy (radioactive isotope decay)

Irradiation (7) Chemicals

Fermentation/

bacteriocins (6)

sources (solar (photovoltaic), wind, wave, hydro)

Steam/

hot water

Sugar preserves, salting

Pressure, light, sound

Gamma rays, X- rays

PEF = Pulsed Electric Field, HPP = High Pressure Processing, IR = Infrared, UHT = Ultra-High Temperature, UV = Ultraviolet

Heat

Solar (heating)

Figure I.1 Types of processing and their preservative effects (chapter numbers for unit operations are shown in parenthesis)

The book is divided into five parts:

Part I describes important basic concepts, including food composition, physical andbiochemical properties, food quality and safety, process monitoring and control andengineering principles

Parts IIIV group unit operations according to the nature of the heat transfer thattakes place; Part II describes operations that take place at ambient temperature or involveminimum heating of foods

Part III includes operations that heat foods to preserve them or to alter their eating qualityPart IV describes operations that remove heat from foods to extend their shelf-life withminimal changes to nutritional quality or sensory characteristics

Part V describes postprocessing operations, including packaging, storage and distributionlogistics

In each chapter, the theoretical basis of a unit operation is first described.Formulae required for calculation of processing parameters and sample problemsare given where appropriate, and sources of more detailed information are indi-cated Details of the equipment used for commercial food production and devel-opments in technology are described Finally, the effects of each unit operation

on sensory characteristics and nutritional properties of selected foods, and theeffects on contaminating microorganisms are described

The book describes each topic in a way that is accessible without an advancedmathematical background, while providing references to more detailed or moreadvanced texts and other sources of information The book is therefore suitable forstudents studying food technology, food science, food engineering, biotechnology

or bioprocessing, and as an additional perspective on their subject areas for studentsstudying nutrition, consumer science, hospitality management/catering, engineering

Readership: Undergraduate and postgraduate students in food technology, foodscience, food marketing and distribution, agriculture, engineering, nutrition, andhospitality management/catering

Part I

Basic Principles

of changes to foods that determine their shelf-life and safety This is followed bymethods used to manage food quality and safety, to ensure authenticity andtraceability, and to monitor and control processes Hygienic design of processingequipment, cleaning and sanitation of processing facilities and waste disposal aredescribed before the chapter concludes with important food engineering principles,including heat and mass transfer, fluid flow and phase and glass transitions.These aspects are expanded on and developed in subsequent chapters that describeindividual unit operations Journals that include research in food science and tech-nology are listed with links to each publication atwww.scimagojr.com/journalrank.phpsubject category ‘Food Science’ Suppliers of food processing services includ-ing processing and materials handling and warehousing equipment manufacturers,control and automation systems, ingredients and packaging suppliers, sanitation andfood safety equipment and supplies are listed at Food Master (www.foodmaster.com/directories).

1.1 Composition of foods

Like all materials, foods are composed of different chemicals and for foodmanufacturers it is the chemical composition that determines all aspects of theirproducts, from the suitability of raw materials for use in particular products andprocesses, to the sensory characteristics and nutritional value of the processedfoods An understanding of food composition and the interactions of food compo-nents enables processors to both design new products and to control the sensoryqualities of foods during processing and storage, thus ensuring that standardisedproducts are produced This section outlines the important properties of the main foodcomponents Basic descriptions of their chemistry are given inAnnex A1available athttp://booksite.elsevier.com/9780081019078/and further details of food chemistry aregiven in a number of textbooks, includingCheung and Mehta (2015),Velisek (2014),Belitz et al (2009), Coultate (2008), Damodaran et al (2007) and Owusu-Apenten(2004) Details of the composition of individual foods are given in publications such asFinglas et al (2014)or in online databases (USDA, 2011;Eurofir, 2016) Research into

Food Processing Technology DOI: http://dx.doi.org/10.1016/B978-0-08-101907-8.00001-8

aspects of food chemistry is reported in the journals ‘Food Chemistry’ (www.journals.elsevier.com/food-chemistry), ‘Agricultural and Food Chemistry’ (http://pubs.acs.org/journal/jafcau) and ‘Journal of Food Composition and Analysis’ (www.journals.elsevier.com/journal-of-food-composition-and-analysis).

In this section, the chemical components of foods are grouped into first themacromolecular components (carbohydrates, lipids, proteins), then water, and finallythe microcomponents, including vitamins, minerals, natural colourants, flavours,toxicants (or bioactive substances) and additives

‘Carbohydrate’ is the generic term for a wide variety of chemicals that form themajor part of the dry matter in plants The simplest forms are ‘monosaccharides’(or ‘simple sugars’) that cannot be further broken down by hydrolysis Other carbo-hydrates that have increasing levels of complexity are disaccharides, trisaccharides,oligosaccharides and polysaccharides A summary of the chemical structure of each

of these carbohydrates is given inAnnex A1.1available athttp://booksite.elsevier.com/9780081019078/

Monosaccharides are the basic units of carbohydrates and they are the simplest types

of sugar They are usually water-soluble, crystalline solids and examples includeglucose (dextrose), fructose and galactose Disaccharides have two monosaccharideslinked together and important ones in foods are:

G Sucrose (a molecule of glucose and a molecule of fructose) is produced commerciallyfrom sugar cane or sugar beet It has a wide variety of forms, including different types ofbrown sugar that contain varying amounts of molasses, white (or crystalline) sugar, oricing or fondant sugar, in which the crystals are ground to a smaller size Sucrose ishighly soluble and concentrated sugar solutions are used in processing and also sold assyrups, which have high osmolality For example, maple syrup is a mixture of
65%sucrose with small amounts of glucose and fructose Sucrose is used as a humectant, as apreservative (e.g in jams and jellies), to increase the boiling point or reduce the freezingpoint of foods, as well as its use as a sweetener Sucrose also reacts with amino acids toproduce the golden brown colour and flavour compounds that are important in baked andfried foods (see also Maillard reactions,Section 1.4.4)

G Lactose (a galactose molecule and a glucose molecule) occurs in milk It is fermented

to lactic acid by lactic acid bacteria in fermented milk products (see Section 6.1.3).The production of the digestive enzyme lactase is genetically controlled and deficiencies

in lactase production increase with age (after
6 years old) and with ethnicity, leading to

a syndrome known as ‘lactose intolerance’ When people have this syndrome, lactosepasses undigested to the large intestine where it undergoes anaerobic bacterial fermentationthat results in bowel irritation and gas production leading to diarrhoea and bloating

G Maltose (two glucose molecules) is formed by hydrolysis of starch Commercially it isproduced by malting grains, especially barley, using β-amylase that is either naturallyoccurring or added after its production by Bacillus spp

All sugars are sweet (as are some other organic and inorganic molecules) but thedegree of sweetness varies considerably InTable 1.1, sucrose is given an arbitrarysweetness value of 1.0 and other sugars are shown relative to that Sweetnessdepends on the presence of OH2groups on the sugar molecule that have a particularorientation, which enables them to interact with protein-based sweetness receptors intaste buds on the tongue.

Honey consists of a mixture of 8083% sugars, mostly glucose and fructose,

in addition to small amounts of other substances, including minerals, vitamins,proteins, amino acids and pollen A wide range of sugar syrups is produced, havingdifferent compositions For example, glucose syrup, containing 90% glucose, ismade by enzymic hydrolysis of starch into oligosaccharides usingα-amylase, whichare then broken down to glucose by glucoamylase This method has largely replacedacid hydrolysis using hydrochloric acid Glucose syrup is used in foods to soften thetexture, add volume, prevent crystallisation of sugar and enhance flavour Syrupsused in confectionery manufacture contain varying amounts of glucose, maltose andoligosaccharides A typical confectioner’s syrup contains 19% glucose, 14% malt-ose, 11% maltotriose and 56% higher-molecular-weight carbohydrates (Hull, 2010;Steinbu¨chel and Rhee, 2005).β-Amylase or fungal α-amylase are used to produceglucose syrups that contain.50% maltose, or 70% maltose in extra-high-maltosesyrup High-maltose glucose syrups are used in the production of hard confectionerybecause they have a lower viscosity than a glucose solution, but still set to a hardproduct Maltose is also a lower humectant than glucose and confectionery producedusing high-maltose syrup does not become as sticky As liquids, all syrups areeasily incorporated into beverages and do not form undesirable crystals in softconfectionery and ice cream, giving these foods a smoother mouthfeel They alsocontribute to the viscosity of condiments and salad dressings

Maize (corn in the United States) is commonly used in the United States asthe raw material for production of ‘corn syrup’, and in other countries cropsincluding potatoes, wheat, barley, rice and cassava are used for syrup production

Table 1.1 Relative sweetness of different sugars

Source: Adapted from Shapley, P., 2012 Taste receptors Available at: http://

butane.chem.uiuc.edu/pshapley/GenChem2/B4/3.html (last accessed January 2016).

High fructose corn syrup (HFCS) is produced by treatment of glucose using glucoseisomerase to produce a mixture of
42% fructose (named HFCS 42) with

5052% glucose HFCS 42 can be further purified into 90% fructose syrup(HFCS 90), or a 55% fructose syrup (HFCS 55) is made by mixing HFCS 90with HFCS 42 in the appropriate ratio HFCS 55 has a comparable sweetness tosucrose, HFCS 90 is sweeter than sucrose and HFCS 42 is less sweet In the UnitedStates, HFCS is the cheapest sweetener for many applications (Schoonover andMuller, 2006; Litchfield et al., 2008) and it is widely used in many different types

of foods and beverages The high fructose content enables HFCS to produceimproved browning in baked products and higher moisture retention, which keepsproducts fresher for a longer period It also produces a softer texture in biscuits(cookies) and snack bars The widespread use of HFCS has prompted a debate onits links to increased obesity and associated illnesses, including cardiovasculardisease and Type II diabetes (Bray, 2007) In the EU and many other countries,sugar production remains important and the large-scale replacement of sugar byHFCS has not occurred to the same extent as the United States

These carbohydrates have short chains of monosaccharides (typically 310 units)and are found in many vegetables, especially beans, leeks, asparagus, cabbage,Brussels sprouts and broccoli, as wells as wheat, oats and other cereals, and mostfruits They are produced commercially by chemical, physical or enzymatic degrada-tion of polysaccharides; or by enzymatic or chemical synthesis from disaccharides

An example of a trisaccharide is raffinose, which comprises galactose, glucose andfructose molecules, and an example of a tetrasaccharide is stachyose, which consists

of two galactose molecules, one glucose molecule and one fructose molecule.Oligosaccharides are one of the nondigestible components of dietary fibre and theypass largely unaltered through the stomach and small intestine of monogastricanimals (e.g humans, pigs and poultry) In the large intestine they can be fermented

by intestinal microflora to produce carbon dioxide, methane and/or hydrogen,leading to flatulence

Oligosaccharides have prebiotic properties (seeSection 6.4.2) and are selectivelyused by probiotic bacteria, including Acidophilus spp and Bifidobacteria spp.,which have been found to suppress pathogens and promote absorption of nutrients.Commercially important oligosaccharides in food products are fructooligosacchar-ides and a series of galactooligosaccharides Others, including xylooligosaccharides,isomaltooligosaccharides and soybean oligosaccharides, are also being developedfor commercial uses as prebiotics The other prebiotic oligosaccharides shown inthe lower part of Table 1.2 are less well documented but research is continuinginto the development of new oligosaccharides that have a range of physiologicalproperties and applications in the food industry

Since oligosaccharides are nondigestible, they provide almost no calories and aretherefore used extensively as sweeteners in low-calorie beverages For examplefructooligosaccharides have approximately one-third to one-half the sweetness ofsucrose with a similar taste profile They can be used to enhance the flavour and

lower the amount of sugar in a product, making it safe for consumption byindividuals with diabetes Galactooligosaccharides are used as humectants in infantformulas and baby foods, and in dairy products (milk beverages/milk substitutes,yoghurt, frozen dairy desserts) Mannan oligosaccharides are used in animal feeds

to improve gastrointestinal health, energy levels and growth performance Otherfood sectors that use oligosaccharides include manufacturers of cereals, vitamin/mineral-fortified energy drinks, and fruit products (fruit drinks, pie fillings, jellies/jams) Moreno and Sanz (2014) and Torres et al (2010) describe the sources,structures, physiological properties and production of oligosaccharides Schweizerand Krebs (2013) describe current research into the biological roles and healthimplications of oligosaccharides

Polysaccharides are the most abundant form of carbohydrates In plants the mostimportant types are starch, cellulose, pectin and a range of gums In animal tissues,glycogen is stored in the liver and muscle tissue as an instant source of energy.The structure of many polysaccharide molecules enables them to form hydrogen

Table 1.2 Oligosaccharides used as prebiotics

Type of oligosaccharide Natural sources Commercial production method Fructooligosaccharides (FOS) Wheat, rye,

asparagus, onion, Jerusalem artichoke

Action of β-fructofuranosidase enzymes, obtained from Aspergillus niger on sucrose or glucose

from starch Soybean oligosaccharides (SOS)

(raffinose and stachyose)

Soybeans Extracted from soybeans

Other oligosaccharides having prebiotic activities that are being studied include:

Arabinooligosaccharides, arabinogalactooligosaccharides, arabinoxylooligosaccharides Gentiooligosaccharides

bonds with water and as a result they readily hydrate, swell and dissolve either tially or completely They are therefore used to control viscosity and to influencethe physical and functional properties of foods (see Section 1.2) They also act ascryostabilisers in frozen foods (i.e they do not depress the freezing point orincrease osmolality as do cryoprotectants), and produce matrices that increase theviscosity of solutions and restrict the mobility of water during freezing They alsorestrict ice crystal growth by absorption to nuclei (seeSection 22.1.1).

Starch is the main carbohydrate found in plant seeds and tubers The most importantcommercial source of starch is maize with other sources being wheat, potato, tapiocaand rice Starch is present in the form of granules, each of which consists of severalmillion starch molecules Starch molecules have two forms: α-amylose (normally

2030%) and amylopectin (normally 7080% depending on the source) Both arepolymers of glucose molecules Amylopectin can be isolated from ‘waxy’ maizestarch, whereas amylose is produced by hydrolysing amylopectin with the enzymepullulanase Their structures are summarised inAnnex A1 available at http://book-site.elsevier.com/9780081019078/ and are described in detail by Chaplin (2014a)andStephen and Phillips (2006) The use of starches in food products is described

by ingredient suppliers (Food Product Design, 2016a; Cargill, 2016; Venus, 2016)and research into starches is reported in the journal ‘Starch’ (http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291521-379X) A video showing starch pro-duction is available atwww.youtube.com/watch?v5 Ei4k4P8WB8Q

There are many types of starch that are cheap, versatile ingredients that havemany uses as thickeners, water binders, emulsion stabilisers and gelling agents.Starch granules produce low-viscosity pumpable slurries in cold water and thickendue to gelatinisation when heated to
80C Different types of starches have differ-ent uses, for example waxy maize starch produces clear, cohesive pastes; potatostarch is used in extruded cereal and snackfood products (seeSection 17.1.1) and indry soup or cake mixes; and rice starch produces opaque gels for baby foods Details

of the uses of different starches are given by ingredient suppliers (Penford, 2016and

in a video atwww.youtube.com/watch?v5 PvT4G-p9DmQ)

Retrogradation (or crystallisation) of starches causes shrinkage and the release

of water (known as ‘synaeresis’) The rate and extent of retrogradation is affected bythe ratio of amylose and amylopectin, the lipid content and solids concentration.Mixing starch withκ-carrageenan, alginate, xanthan gum (seeSection 1.1.18) or low-molecular-weight sugars can also reduce retrogradation Details of starch gelatinisa-tion and retrogradation are given by BeMiller and Whistler (2009), Palav andSeetharaman (2006), Xie et al (2006)and Eliasson (2004) At high concentrations,starch gels are both pseudoplastic and thixotropic (seeSection 1.2.2) Their water-binding ability is used to provide texture to foods and they are used as a fat substitutefor low-fat versions of foods such as salami, sausages, yoghurt and bakery products(Abbas et al., 2010) (see alsoSection 1.1.2)

Some types of starch are rapidly digestible (e.g the starch in boiled potato) andothers are ‘slowly digestible’ (e.g the starch in boiled millet), which reduce

postprandial blood glucose peaks and are useful in diabetic diets A significant portion of starch in the diet is not digested in the stomach and small intestine and isknown as ’resistant’ starch, which is considered to be a dietary fibre that may haveimportant physiological roles The amount of resistant starch in a food depends on

pro-a number of fpro-actors, including the form of the stpro-arch pro-and the method of cookingprior to consumption Four different types of resistant starch have been identified as

G Type I, physically inaccessible starch (due to intact tissues or other large particulate materials)

G Type II, ungelatinised starch (due to the physical structure of uncooked starch granules,for example in banana)

G Type III, retrograded starch (due to the physical structure of starch molecules after theyare gelatinised, for example in stale bread)

G Type IV, chemically modified starch (resulting from chemical modification, such as linking, that interferes with its digestion)

Starches can be modified to improve their functional properties (e.g increasedsolubility, increased or decreased viscosity, freeze/thaw stability, enhanced clarityand sheen, improved gel strength and reduced synaeresis) Modification also enablesstarches to withstand conditions of high shear, high temperatures and/or acidic condi-tions There are many types of modified starches, including crosslinked, oxidised,acetylated, hydroxypropylated and partially hydrolysed materials (Table 1.3)

Table 1.3 Properties and applications of modified starches

Process Function or property Examples of applications

Acid conversion Viscosity lowering Gum confectionery (forms the shell of

jelly beans), formulated liquid foodsConversion to

dextrins

Binding, coating,encapsulation

Confectionery, baking (higher crustgloss), flavourings, spices, oilsCrosslinking Thickening, stabilising,

creating suspensions,texturizing

Pie fillings, bakery products, puddings,infant foods, soups, salad dressings

Esterification/

etherification

Stabilisation, temperature storage

low-Emulsions (e.g in French dressingmodified starch envelops oil dropletsand suspends them in the liquid phase),soups, frozen foods (modified starchreduces drip losses when defrosted)Oxidation Adhesion, gelling Formulated foods, batters (it increases

the stickiness of batter for friedfoods), gum confectioneryPregelatinisation Cold water swelling Causes instant desserts to thicken with

the addition of cold water or milk

Source: Adapted from Yao, Y., 2015 Starch: structure, function and biosynthesis Available at: www.academia.edu/ 5027874/Starch_yao (last accessed January 2016).

Other examples of modified starches are alkaline-treated starch, bleached starch,enzyme-treated starch, monostarch phosphate, distarch phosphate, phosphated dis-tarch phosphate, acetylated distarch phosphate, starch acetate, hydroxypropyl starchand hydroxypropyl distarch phosphate Their uses include:

G thickening cheese sauce or gravy without producing lumps in the product when boilingwater is added to dried granules;

G modified starch bonded with phosphate absorbs more water and holds ingredientstogether;

G partially hydrolysed starch is used in sauces to control their viscosity

When starch is hydrolysed into simpler carbohydrates, the extent of conversion

is quantified by the ‘dextrose equivalent’ (DE), which relates to the fraction of theglycosidic bonds that are broken (see Annex A1 available at http://booksite.else-vier.com/9780081019078/) Microbial enzymes are used commercially to produce avery large number of derivative ingredients including dextrose (DE 100), cornsyrups (DE 3070) and maltodextrin (DE 1020) Details are given by BeMillerand Whistler (2009)andEmbuscado (2014)

Cellulose consists of unbranched chains of glucose molecules that form a mensional structure of microfibres, which combine to form cellulose fibres, eachone typically containing
500,000 cellulose molecules Cellulose has a crystallinestructure that has a high tensile strength and is the structural molecule in plants thatsupports stems and leaves In contrast to other more amorphous polymeric carbohy-drates, the crystalline structure also makes cellulose insoluble in water and resistant

three-di-to enzymic breakdown Cellulose has many uses, including an anticaking agent,emulsifier, stabiliser, dispersing agent, thickener, gelling agent and a packagingfilm (seeSection 24.2.4) Additional details of the properties of cellulose are given

by Chaplin (2014b) The use of cellulose and its derivatives in food products isdescribed by ingredient suppliers (Food Product Design, 2016b) Research into cel-lulose and its products is reported in the journal ‘Cellulose’ and research papers oncellulose are available to purchase fromhttp://link.springer.com/journal/10570.Hemicelluloses have amorphous branched structures composed of a variety ofsugars, including xylose, arabinose and mannose, which can become highly hydrated

to form gels Cellulose or hemicelluloses cannot be digested by monogastricanimals and form dietary fibre that passes essentially unchanged through the smallintestine (ruminant herbivores digest cellulose using cellulase- and hemicellulase-producing bacteria in their forestomachs or large intestines) Further information onpolysaccharide digestion is given byBowen (2006)

Cellulose may be modified to impart specific functional properties (Table 1.4).Microcrystalline cellulose (MCC) is produced by hydrolysis of cellulose andseparation of the constituent microcrystals The powdered form is used as a flavourcarrier and anticaking agent and a colloidal form has properties that are similar togums (seeSection 1.1.1.8) Carboxymethylcellulose (CMC) is produced by reacting

Table 1.4 Properties and applications of cellulose derivatives

Type of cellulose derivative Properties Functions and applications

Ethylcellulose (EC) Nonionic Film former

Hydrophobic Flavour fixative Soluble in organic

solvents

Limited food approval for use

in flavour encapsulation, moisture barrier films

Thermoplastic Ethylmethyl cellulose (MEC) Nonionic Thickening agent, filler,

anticlumping agent, emulsifier

pH stable Precipitates from solution above 60 C(reversible upon cooling)

Used in non-dairy creams, calorie ice-creams, whipped toppings, mousses Hydroxypropyl cellulose

low-(HPC)

Nonionic Thickener, emulsifier, foam

stabiliser, flexible film former Surface active

Insoluble in hot water ( 40 C) Used in whipped toppings, ediblecoatings, confectionery glazes,

extruded foods Soluble in organic

solvents Thermoplastic Methylcellulose (MC) and

hydroxypropyl

methylcellulose (HPMC)

Produce heat-reversible gels

Binding, film former, freeze thaw stability

Cold water soluble Used in formed foods, fillings,

sauces, whipped toppings, gluten substitutes in gluten-free bakery products

pH stable Wide viscosity range Microcrystalline cellulose

(MCC)

Thixotropic Opacifying agent (causes

opaqueness), foam stabiliser, bulking agent, moisture regulator, anticaking agent, emulsifier, freeze thaw stability

Reversible shear thinning Heat stable Nonionic Powdered and dispersible grades available

Used in powdered or shredded cheese, beverages, confectionery, salad dressings, sauces, whipped toppings

Sodium

carboxymethylcellulose

(CMC)

Anionic Freeze thaw stability, protein

protection, thickener, texture control

pH-sensitive Interacts with proteins High water-holding capacity

Used in frozen foods, bakery products, soups, sauces, beverages

Source: Adapted from Deyarmond, V., 2012 Cellulose derivatives in food applications Dow Wolff Cellulosics, Intermountain Chapter, Institute of Food Technologists Available at: http://intermountainiftpresentations.wordpress.com search ‘cellulose’ (last accessed January 2016) and Granstro¨m, M., 2009 Cellulose derivatives: synthesis, properties and applications Academic Dissertation Faculty of Science, University of Helsinki Available at: https://helda.helsinki.fi/bitstream/handle/10138/21145/ cellulos.pdf? 2 (last accessed January 2016).

cellulose with chloroacetic acid This produces a wide range of viscous solutionsthat are used, e.g to stabilise protein solutions such as egg albumin before drying

or freezing, and to prevent casein precipitation in milk products Methylcellulosesand hydroxypropylmethylcelluloses (HPMC) are the most widely used cellulosederivatives in the food industry They have surface active properties that can beused to stabilise emulsions and foams (see Section 1.2.3) They are used in soyburgers where they add meat-like texture to the vegetable proteins and they are alsoused to reduce the amount of fat in products (seeSection 1.1.2) by both providingfat-like properties and reducing fat absorption in fried foods (seeSection 18.1.3).Their gel structure provides a barrier to oil and moisture and acts as a bindingagent Details of different cellulose derivatives are given by Wuestenberg (2014)and their use in food products is described by ingredient suppliers (ISI, 2016)

Polysaccharide gums (or hydrocolloids) are derived from plants, such as guar,locust bean, gum arabic from Acacia trees and pectin from citrus skins or applepomace Carrageenan and alginates are extracted from seaweed and xanthan gum

is produced by microbial fermentation They are used in low concentrations(e.g 0.251%) for a number of purposes: they thicken aqueous solutions; formgels; stabilise, modify and control the properties of liquid foods, allowing otheringredients to be dispersed and suspended in them; or they modify the texture ofsemisolid foods They can also be used as emulsifiers Gums are a source of dietaryfibre and can be used in reduced-calorie foods to replace fat (seeSection 1.1.2).They are also used in gluten-free foods, since they can be eaten by people whoare intolerant to gluten Gums are also suitable for vegetarians, vegans and peoplewith religious dietary restrictions (e.g Kosher/Halal)

The selection of a hydrocolloid for a particular application is complicated anddepends on many factors including, e.g the required strength or rheology of the gel,the pH, ionic strength and temperature of the food, and presence of other ingredientsthat may interact with the hydrocolloid Details of the uses of hydrocolloids infood products are given by Nussinovitch and Hirashima (2013), Laaman (2011),Hoefler (2004),Phillips and Williams (2009)and by ingredient suppliers (ISI, 2016;FMC, 2016) Research into gums is reported in the journal ‘Food Hydrocolloids’(www.journals.elsevier.com/food-hydrocolloids) A summary of common food gums

is given inTable 1.5

The distinction between ‘fats’ and ‘oils’ is based solely on whether a lipid is solid orliquid at room temperature The three types of edible fats and oils includevegetable oils, animal fats and marine oils They are consumed directly as butter,margarine, salad and cooking oils, and they are used as ingredients in a very widerange of processed foods as well as animal feeds, cosmetic products, paints and lubri-cants About three-quarters of worldwide consumption of fats and oils are in food

Type of gum Source Uses Notes/examples of applications Sources of further information

forming a strong gel Gelling agent in yoghurt

Ingredient suppliers (AEP,

gels with calcium ions

Reformed fruit pieces or dessert gels Propylene glycolalginates are less sensitive to acidity and calciumions, and are used to thicken or stabilise dairyproducts and salad dressings

Molina and Quiroga (2012)

gelling agents

Three types are ‘kappa’, ‘iota’ and ‘lambda’: kappa gelsare strong and brittle, iota gels are softer and moreresilient and have good freeze/thaw stability; lambdacarrageenans are soluble and nongelling Used inchocolate milk to prevent cocoa particles fromsettling out, to stabilise freeze/thaw cream and airbubbles in ice cream, and improve water-holdingcapacity and reduce cooking losses in meat products

Chaplin (2014c)

Cassia tora andCassiaobtusifoliaseeds

Thickener and stabiliser Excellent retort stability Forms strong synergistic gels

with other hydrocolloids including carrageenan andxanthan gum

Ingredient suppliers (Food

bySphingomonaselodea

Gelling, stabilising orthickening agent

Has a wide range of textures, from a light pourable gel

to a thick, spreadable paste Suspends fibre and pulp

in fortified beverages and milk solids in milk drinks

Ingredient suppliers (Kelko,

Cyamopsistetragonoloba

Thickening agent, binderand volume enhancer

Used frequently with other gums High in solubledietary fibre (8085%) and added to bread toincrease fibre content Used to thicken and stabilisesalad dressings and sauces and improve moistureretention in bakery products

Chaplin (2014d)

(Continued)

Type of gum Source Uses Notes/examples of applications Sources of further informationGum arabic

‘bloom’ in chocolate Used as a glaze for pan-coatedconfectionery

Ingredient suppliers (Danisco,

apple peels/

pomace orsugar beetpomace

Gel formation, thickeningand stabilising

Fruit-based products and yoghurts, confectionery andfruit drinks High-methoxyl pectins form gels withhigh sugar concentrations and acid (e.g jams, jellies,marmalades); low-methoxyl pectins form gels withcalcium ions, thus requiring less sugar (e.g diabeticpreserves)

Ingredient suppliers (ISI, 2016;

Thickener, stabilisessuspensions andemulsions, strong water-binding properties

Has unusual properties: soluble in both hot and coldwater; produces a high viscosity at low

concentrations with no change in viscosity from 0C

to 100C; stable in acidic foods and after exposure

to freezing/thawing; compatible with salt Used inbakery products to prevent water migration fromfillings into the pastry

Ingredient suppliers (ISI, 2016;

a Other gums include gum karaya, gum ghatti and gum tragacanth.

b Treatment of pectins with ammonia and methanol produces amidated low methoxyl pectins Amidation causes pectin to gel at higher temperatures compared to nonamidated pectin and requires less calcium.

applications (IHS, 2012) and there has also been increased use of edible oils forbiodiesel production The main producing countries are in Asia, accountingfor 50% of world edible fats and oils production (Table 1.6) of which palm oiland soybean oil were
50% of the total in 2013, and palm kernel oil ( 33% ofthe total).

Animal fats have lower production and consumption and marine oil productionhas reduced substantially (IHS, 2012) There are also a large number of nut oils,including almond, cashew, hazelnut, macadamia, mongongo nut, pecan, pine nut,pistachio and walnut Because of their individual flavours, these are used as culi-nary or salad oils and are also widely used in cosmetics and for aromatherapy.Other seed oils have similar applications, including those extracted from grapefruitseed and the seeds of gourds, melons, pumpkins, and squashes A very largenumber of other oils are used as ‘essential’ oils for flavouring, for aromatherapy or

as food supplements (or nutraceuticals) due to their nutrient content or purportedmedicinal effects Details of the range of available oils are given by suppliers(EOD, 2016; Essential Oil Company, 2016) Methods used to extract culinaryand essential oils are given in Sections 3.3 and 3.4

Fats and oils are composed of mono-, di- and triesters of glycerol with fatty acids,known as ‘monoacylglycerols’, ‘diacylglycerols’ and ‘triacylglycerols’, respectively.The types of fatty acids in a particular lipid depend on the animal or crop sourceand, in crops, whether they have been selectively bred to achieve a particularratio of fatty acids (e.g canola was selectively bred from rapeseed to reducethe amounts of glucosinolates and erucic acid because these are considered

to be inedible or toxic in high doses) The properties of lipids, including theircomposition, structure and melting points are described inAnnex A1.2available at

Table 1.6 Producing countries of the main edible oils and fats

Type of oil or fat Main producing countries

Cocoa butter Malaysia, Indonesia, Ghana

Coconut oil Philippines, Indonesia

Groundnut (peanut) oil China, Indonesia, Nigeria

Maize (corn) oil United States

Olive oil Spain, Italy, Greece

Palm kernel oil Malaysia, Indonesia, Nigeria

Rapeseed oil/canola oil China, Germany, Indonesia, CanadaSafflower seed oil India, United States, Mexico

Sesame seed oil China, Myanmar, India

Soybean oil United States, Brazil, China, ArgentinaSunflower seed oil Russian Federation, Argentina, Ukraine

Source: From FAO, 2012 FAOSTAT Available at: http://faostat3.fao.org (last accessed January 2016).