Nanotechnologies in Food

Qasim Chaudhry, Laurence Castle, Richard Watkins, Qasim Chaudhry, Laurence Castle, Richard Watkins

• Publisher: Royal Society of Chemistry
• Year: 2017
• ISBN:
  9781788011365
• Edition: 2
• Topic: Technology & Engineering
• Subtopic: Food Science
• Index: Technology & Engineering

Nanotechnologies in Food provides an overview of the products and applications of nanotechnologies in agri-food and related sectors. Following on from the success of the first edition, this new edition has been revised and updated to bring the reader fully up to date on the emerging technological, societal, and policy and regulatory aspects in relation to nanotechnologies in food. This book contains new chapters discussing some of the aspects that have attracted a lot of debate and research in recent years, such as how the regulatory definition of 'nanomaterial' is shaping up in Europe and whether it will result in a number of exciting food additives being regarded as nanomaterials, how the new analytical challenges posed by manufactured nanoparticles in food are being addressed and whether the emerging field of nano delivery systems for food ingredients and supplements, made of food materials or other soft/degradable polymers, can raise any consumer safety concerns. The edition concludes by discussing the future trends of the technological developments in the area of nanotechnologies and potential future 'fusion' with other fields, such as biotechnology and synthetic biology. This book provides a source of much needed and up-to-date information on the products and applications of nanotechnology for the food sector - for scientists, regulators, and consumers alike. It also gives an independent, balanced, and impartial view of the potential benefits as well as risks that nanotechnology applications may bring to the food sector. Whilst providing an overview of the state-of-the-art and foreseeable applications to highlight opportunities for innovation, the book also discusses areas of uncertainty in relation to public perception of the new technological developments, and potential implications for consumer safety and current regulatory controls. The book also discusses the likely public perceptions of nanotechnologies in the light of past technological developments in the food sector, and how the new technology will possibly be regulated under the existing regulatory frameworks.

Chapter 1

Nanotechnologies in Food: What, Why and How?

QASIM CHAUDHRY^a, RICHARD WATKINS^b AND LAURENCE CASTLE^c

^a Institute of Food Science and Innovation, University of Chester, Parkgate Road, Chester CH1 4BJ, UK

^b Defra, National Agri-Food Innovation Campus, Sand Hutton, York YO41 1LZ, UK

^c Formerly, The Food & Environment Research Agency, York, UK

^* E-mail: [email protected]

1.1 Background

The possibility of controlling and manipulating certain properties of materials and substances by reducing their particle size to very small scales has been hypothesized since 1959.¹ The term ‘nanotechnology’ has been coined in the past few decades to encompass different processes, materials and applications derived from a wide range of fields in the physical, chemical and biological sciences and in electronics and engineering with the common theme of the manufacture and use of materials on a nanometre size scale. One nanometre is one-billionth of a metre (1 × 10⁻⁹ m). The advent of modern analytical tools that can detect and characterize the various physicochemical aspects of materials at the nanoscale has further boosted developments in this field and nanotechnology has started to provide a systematic method for the study and fine-tuning of material properties to suit specific applications. This has inevitably attracted much interest from virtually all industrial sectors for the development of new or improved products and applications based on nanomaterials. Of particular interest in this regard are engineered nanoparticles (ENPs), which are manufactured specifically to achieve a certain composition or material property or composition for a particular purpose.

Like any new emergent field of science and technology, nanotechnology has brought both the promise of a number of new prospects and applications and new challenges. For example, it has not been easy to provide an exact definition of a nanomaterial. Despite several proposals, an internationally agreed definition is not yet on the horizon (see Chapter 2). Nevertheless, as a result of the commonality between different facets of nanotechnology in terms of a nanoscale particle size, there is a broad understanding that a typical nanomaterial could be characterized as having one or more external dimensions in the size range 1–100 nm.² Nanomaterials can be in the form of nanoparticles, where all three external dimensions are at the nanoscale; nanorods or nanotubes, where two dimensions are at the nanoscale; and coatings or sheets, where only one dimension is at the nanoscale (Figure 1.1).

Figure 1.1 Nanomaterials as (a) particles; (b) rods; and (c) layers.

The chemical nature of the substances that can be used to manufacture ENPs is very diverse. In theory, any particulate material can be produced in nanoform either by a top-down (i.e. grinding down larger materials to the nanoscale) or a bottom-up (i.e. the upwards assembly of atoms/molecules to build nanoscale particles) approach. A nanomaterial can therefore be inorganic, organic or hybrid in nature. In addition to manufactured nanoparticles, some nanomaterials can be derived from natural sources—for example, montmorillonite is a clay obtained from volcanic ash or rocks. It has a natural nanoplate structure and has been used as a nanofiller in food packaging applications.

Nanomaterials are generally produced in the form of primary particles with nanoscale dimensions. However, most nanoparticles have a tendency to stick together to form larger agglomerates and/or aggregates during subsequent processing, formulation or storage. Unlike aggregates in which the primary particles are strongly bound together, these agglomerates only hold the primary particles together through weak van der Waals forces. The agglomerates can therefore de-agglomerate with changes in certain conditions, such as pH or ionic strength. Nanomaterials may be present as free particles in some applications, such as cosmetics and personal care products, but in other applications they are present as fixed, bound or embedded forms in a matrix, such as food packaging materials. Thus a nanomaterial may be present in a product in the form of free (separate from each other) nanoparticles and as larger sized clusters depending on the type of product or application.

To help visualize nanomaterials in context, organic life is carbon-based and the C–C bond length is about 0.15 nm. Thus, when placed in a food context, most ENPs are larger than molecules such as lipids, are a similar size to many proteins, but are smaller than the intact cells in plant- and animal-based foods (Figure 1.2).

Figure 1.2 Nanomaterials in the size context of other components of food.

The fundamental drivers at the heart of most nanotechnology applications are the potential for improvement in material properties, the development of new functionalities and/or a reduction in the amount of (chemical) substances needed for a function. This is because, on an equivalent weight basis, the nanoforms of a material will have a much larger surface to mass ratio than their conventional bulk equivalents. Thus a much smaller amount of an ENP could, in theory, provide the level of functionality that would otherwise require a much greater amount of the same material in conventional form. The notion ‘a little goes a long way’ is probably the single most powerful reasoning behind many nanotechnology applications. Other benefits have also been attributed to the very small dimensions of ENPs—for example, nanosizing may allow the conversion of water-insoluble substances to forms that are dispersible in aqueous formulations. This may make it possible to reduce the need for solvents in certain consumer products, such as cosmetics, paints and coatings. The similar processing of water-insoluble food additives, such as colours, flavours and preservatives, may improve their dispersion in low-fat products. Nanoforms of various nutrients and supplements have also been claimed to have a greater uptake, absorption and bioavailability in the body than their bulk equivalents. This aspect alone has attracted a lot of interest in the use of nanosized ingredients in supplements, nutraceuticals and (health) food applications.³

The current applications of nanotechnology span a wide range of sectors, predominantly cosmetics and personal care, health care, paints and coatings, catalysts, agri-food, packaging and electronics. Nanotechnology applications have also been widely regarded to have the potential to revolutionize the whole of the agri-food sector, from production, processing, packaging and transportation to storage. Examples may include greater nutritional/health benefits, new or improved tastes, textures and flavours and also food products with lower amounts of additives, such as sugar, salt, fat, and artificial preservatives, colours and flavours. Nanotechnology applications for food packaging have also enabled the development of lightweight yet strong packaging materials that are able to keep foodstuffs secure during transportation, fresh for longer and safe from pathogens. Innovative smart labels incorporating ENPs are being developed to provide warnings to the consumer when a packaged food has started to deteriorate. Another emerging R&D and application area relates to the use of nanosized carriers for the enhanced delivery of nutrients and other bioactive substances in supplements, nutraceuticals, cosmeceuticals and health food products.⁴ Such formulations are generally derived from the nanoscale processing of food materials to form micelles or liposomes, or encapsulating bioactive supplements in natural or synthetic biodegradable polymeric materials. Any enhancement in uptake and bioavailability, or targeted release in the body, of certain poorly absorbed minerals and other health-promoting supplements may benefit consumers in general and certain population groups—such as elderly people, patients, and sportspersons—in particular.

Nanotechnology has emerged as one of the major converging technologies, offering the potential for further new developments through integration with other scientific and technological disciplines. There are already examples where the integration of nanotechnology with biotechnology and information technology has enabled the development of miniaturized sensing and monitoring devices, such as nanobiosensors. Such developments can be expected to enable the detection of pathogens and contaminants in food during processing, transportation and storage, and to enhance the safety and security of food products. In view of the known and envisaged technological developments, it is not surprising that the food industry is among those sectors eagerly seeking ways to realize the potential benefits offered by nanotechnology.

This book aims to provide an impartial view of the prospects and benefits that nanotechnology can be expected to bring to the food sector, the potential risks associated with these new materials and applications, and questions about the relevant societal and regulatory issues. This first chapter sets the scene for the subsequent chapters on different aspects of nanotechnologies in food, with each chapter written by experts acknowledged to be leaders in their respective fields.

1.2 Technological Advances in the Food Sector

The main driver that has shaped the present day food industry is the continuous basic human quest for a sustained supply of safe, nutritious, diverse, affordable and enjoyable foodstuffs. Our food has gone through a long history of transformations over the centuries, from hunting and gathering to highly mechanized farming and technologically advanced methods for processing and preservation. Agricultural food production during early human settlements is known to have started with instinctive knowledge and elementary tools and was at the mercy of the climate, pests and pathogens. Knowledge and experience gained over generations enabled different civilizations to live off the land and paved the way for more systematic farming and animal breeding. However, our basic food production methods seem to have remained more or less unchanged over the millennia. Until the early 1900s, agriculture was still run as a family-controlled or community-owned affair in most parts of the world. The norms of food production, transportation and trade started to transform in the 20th century with the introduction of mechanized farming, high-yielding crop varieties and, later, with the availability of synthetic fertilizers, pesticides and other agrochemicals (e.g. antibiotics and hormones). The so-called ‘green revolution’ of the mid-20th century succeeded in substantially increasing global food production. As the production of global food reached industrial scales, new ways had to be found to transport, store and preserve foodstuffs. This laid the foundations of the modern day food industry. In recent decades, advancements in DNA technology have led to a better understanding of the fundamental biological principles and genetic mechanisms involved in food production, which has enabled further large leaps from protracted conventional breeding methods to faster, knowledge-based improvements in crops and farm animals.

The history of food processing is as old as that of food production. Through the centuries, foodstuffs have been processed and treated in various ways and blended with different ingredients and additives to kill pests and pathogens, to enhance nutritional value, taste, flavour and texture, and to keep and store foodstuffs for longer periods of time. In that respect, many of the processes used by the modern day food industry—for example, heat treatment, fermentation, acid hydrolysis, kilning, curing, smoking and drying—are not new. However, the present day consumer-driven food industry has to constantly look for innovation and to develop new products that not only offer new tastes, textures and flavours, but are also wholesome, nutritious and better value for money for consumers. The present day food sector is a gigantic and complex web of subsectors and branches spanning from farm to fork. The global food retail market alone was estimated to be worth US$5.8 trillion annually in 2014.⁵ With the globalization of trade and industry worldwide, the rigid national boundaries that existed to protect local food production and supply are gradually becoming obscure and the supply and demand of foodstuffs is now increasingly influenced and determined by global market forces. In this context, the introduction of nanotechnology is likely to make new waves in the already very competitive and technologically advanced food industry. These aspects are discussed in more detail in subsequent chapters.

1.3 Public Consent for Technological Innovation

Before becoming established, any new technology has to cross a number of technological, societal and regulatory barriers, especially when it is applied to a sensitive area such as food. The applications of nanotechnology to food are facing this challenge. Despite the new emergent nature of nanotechnology applications to food, there have already been calls for clarity on whether and how the new technological developments would bring any real benefits for consumers and not just for the industry alone, and whether the benefits outweigh any risk to consumer health and the environment.

The early stages of any new technology are generally associated with a high level of uncertainty. Building consumer confidence and trust to encourage acceptance of the novelty determines the ultimate success or failure of the technology. Food products derived from nanotechnology are currently unfamiliar and unknown to the public at large, and it remains to be seen how such developments will be viewed by consumers. Uncertainties due to a lack of knowledge, or a lack of clear communication, are known to raise concerns over real as well as perceived risks. This is evident from the recent debacle over genetically modified foods. Despite the lack of analogy with genetically modified foods, nanofood applications seem to have opened up a similar debate among stakeholders, with calls for a ...

Table of contents

• Cover
• Title
• Copyright
• Preface to First Edition
• Preface to the Second Edition
• Contents
• Chapter 1 Nanotechnologies in Food: What, Why and How?
• Chapter 2 The Devil is in the Definition
• Chapter 3 Acceptance of Agri-Food Nanotechnology: Insights from the Evolution of Food Technology, Novel Foods and the Psychology of Novel Food Acceptance and Evidence from Present Research
• Chapter 4 Public Perceptions of Nanotechnologies: Lessons from Genetically Modified Foods
• Chapter 5 Natural and Processed Food Nanostructures
• Chapter 6 Supplement Delivery at the Nanoscale
• Chapter 7 Nanotechnology in Food Packaging
• Chapter 8 Nanomaterials in Food Products: A New Analytical Challenge
• Chapter 9 Potential Benefits and Market Drivers for Nanotechnology in the Food Sector
• Chapter 10 Engineered Nanoparticles and Food: Exposure, Toxicokinetics, Hazards and Risks
• Chapter 11 Infinitesimal Ingredients: An Analysis of the Regulatory Dimensions of Nanotechnologies in Foods and Food Contact Materials
• Chapter 12 Nanotechnologies in Food: The Knowns, Unknowns, and Unknown Unknowns
• Subject Index