Rickey Yada opened the meeting with his introductory presentation, Nanotechnology: A New Frontier in Foods, Food Packaging, and Nutrient Delivery. Yada provided an overview of the definition(s) and history of nanotechnology, emphasizing that food scientists and technologists have been working with naturally existing nanomaterials and nanoscale phenomona long before modern-day nanotechnology emerged; an overview of the different types of modern-day nanotechnologies being applied in the food industry and how they are being or could be applied; and a summary of key issues that will need to be addressed as the field moves forward. He emphasized the need to fill gaps in understanding the benefits, safety, and environmental consequences of using nanotechnology in food; and the need for transparency and the establishment of public trust. Yada touched on many issues that would be revisited in greater detail or at greater length later during the workshop. A summary of his presentation follows. But first, this chapter begins with a summary of the several major themes that emerged over the course of the day’s dialogue.
MAJOR WORKSHOP THEMES
Several major workshop themes emerged over the course of the day, with issues pertaining to each being revisited by multiple speakers and at different times during the open discussions:
Workshop presenters described many potential applications of nanotechnology in foods, food packaging systems, and other areas of food and nutrition science and technology. Some of these applications have already appeared in consumer goods, although most are still in the research and development phase. Rickey Yada, Jose Aguilera, Frans Kampers, and Jochen Weiss each described some of these applications during their presentations. However, as Yada and, later, Martin Philbert, stated, there is a difference between “nano-fact” and “nano-fiction”: many of the more “futuristic” applications being touted (not just in food but with nanotechnology in general) may never be realized.
Throughout the day, presenters and other workshop attendees touched upon a wide range of potential benefits of these applications. The potential benefits of food nanotechnology extend across many different areas of food and nutrition science and technology, including basic research (e.g., the use of nanoscale instrumentation to analyze nanoscale food processing phenomena in ways not possible in the past), nutrition (e.g., the use of nanomaterials to encapsulate and deliver nutrients to targeted tissues), food technology (e.g., the use of nanotechnology-based labels on food products as a way to provide consumers with real-time information about the quality of the product), and even medicine (e.g., the use of nanomaterial-based nutrient delivery systems as an interventional health strategy).
Workshop presenters identified several gaps in knowledge about the nutritional and safety consequences of introducing nano-sized structures into foods, and several participants expressed uncertainty about how best to evaluate the potential benefits versus risks of nanotechnology. During their presentations, both Aguilera and Philbert described some of the gaps in knowledge about what happens to nanomaterials when introduced, firstly, into a food matrix and, secondly, into the human body. As Philbert elaborated, along with intended (and ancillary) benefits, there will likely be unintended adverse effects. For example, there may be unanticipated risks associated not so much with the actual nanomaterials but with some of the other, non-nano substances used to ensure that the nanomaterials behave in their intended manner. So far, no real safety issues or incidents have been identified. But as the field moves forward, as both Philbert and Jean Halloran emphasized, weighing the potential benefits against potential risks will be crucial to developing food nanotechnology into a safe and effective tool. However, as evident by discussion at the end of Sessions 2 and 3 (and as summarized in Chapters 3 and 4), there are many uncertainties around both how the benefits and risks can and should be measured and what specific regulatory measures can and should serve as a framework for evaluation.
There was considerable discussion around the regulatory measures already in place for examining the benefit-risk balance of nanotechology applications in food and the likely need for more complete guidance in the future. During her presentation, Laura Tarantino argued that statutory authorities already provide the U.S. Food and Drug Administration (FDA) with the necessary tools for evaluating and regulating the safety of nanomaterials with novel properties and that the FDA’s existing procedures and systems are adequate for evaluating and regulating nanotechnology in food. Tarantino encouraged early and frequent consultation with the FDA so that manufacturers can get a sense of what will be expected of them when their product(s) are ready for review. Fred Degnan agreed with Tarantino about FDA’s existing statutory authorities but emphasized the necessity of having at least some sort of written guidance available to industry, even if that guidance is only preliminary and tentative. There was considerable discussion at the end of Sessions 2 and 3 about the timeline and direction of next steps and future options for the FDA and other regulatory agencies.
While many workshop participants agreed that engaging the public is necessary in order to build understanding and ultimately acceptance of this emerging technology, there are still some unanswered questions about how best to proceed. As presenter Julia Moore elaborated, public opinion of nanotechnology is “up for grabs,” with very few people knowing anything at all about the use of nanotechnology in food. Now is the time to act, she said. But, as with many of the other issues up for discussion during the workshop, there is uncertainty about how to proceed. For example, while commending presenter Carl Batt for his group’s nanotechnology public education efforts, Halloran also questioned whether education necessarily translates into acceptance. As another example, when asked whether there are particular types of nanomaterials or nanotechnology applications that consumers would be more willing to accept in foods, Halloran remarked that the issue is not whether consumers are for or against nanotechnology, rather whether or not nanotechnology provides actual benefits to consumers and is safe. There was considerable discussion at the end of Session 3 on this topic, with participants commenting on consumer choice and decision making (e.g., how consumers perceive benefit and risk), use of the word nanotechnology (e.g., compared to what some participants argued was the more accurate “nanotechnologies”), lessons to be learned from the biotechnology experience, and other related issues.
Again, the purpose of the workshop was neither to reach consensus on any single issue nor come to any conclusions about specific next steps. In fact, an overarching theme of the workshop presentations and discussion was the uncertainty that still exists regarding how best to move forward on several scientific (e.g., how to evaluate both the benefits and risks of adding synthetic nanomaterials to foods) and societal (e.g., how to engage the public) fronts.
NANOTECHNOLOGY: A NEW FRONTIER IN FOODS, FOOD PACKAGING, AND NUTRIENT DELIVERY1
Presenter: Rickey Yada2
Yada began by remarking that nanotechnology holds forth much promise as a means of providing novel solutions to many of the greatest problems facing the world today, from energy production (i.e., finding new ways to produce plentiful, low-cost energy) to food and clean water shortages. As just one example, he identified water shortage as one of Canada’s biggest problems, with Alberta utilizing a tremendous amount of non-reusable water for oil recovery; nanotechnology may provide a means to reuse that water.
The Definition(s) and History of Nanotechnology
Before describing some of the details of potential applications of nanotechnology in food, Yada talked about the definition(s) and history of nanotechnology. First, what is nanotechnology? There are several definitions:
From the National Cancer Institute website3: “Technology development at the atomic, molecular, or macromolecular range of approximately 1–100 nanometers to create and use structures, devices, and systems that have novel properties.”
Also from the National Cancer Institute website4: “Technology on the nanometer scale. The original definition is technology that is built from single atoms and which depends on individual atoms for function. An example is an enzyme. If you mutate the enzyme’s gene, the modified enzyme may or may not function. In contrast, if you remove a few atoms from a hammer, it still will work just as well. This is an important distinction that has generally been lost as the hype about nanotechnology and it is used as a buzzword for ‘small’ instead of a distinctly different technology. Fortunately real nanotechnologies are in the works….”
From the European Union–funded NanoHand project website 5: “Nanotechnology comprises the emerging application of Nanoscience. Nanoscience is dealing with functional systems either based on the use of sub-units with specific size-dependent properties or of individual or combined functionalized sub-units.”
From the National Nanotechnology Initiative (NNI): The NNI considers something “nanotechnology” only when nanotechnology tools and concepts are used to study biology; biological molecules are engineered to have functions very different from those they have in nature; and manipulation of biological systems is done by methods more precise than can be done by using molecular biological, synthetic chemical, or biochemical approaches that have been used for years in the biology research community.
Elsewhere, nanotechnology is often generally defined as any technology dealing with objects within the 1–100 nm range. But without having a sense of what kind of objects are 1–100 nm long, many people have a difficult time relating to this length scale. Yada considered the fourth definition above to be the “most pragmatic.” Even more useful, he said, is defining nanotechnology and nanoscience by using a visual display of nanosized natural and manufactured objects, so that consumers and the public can see descriptive objects in relationship to the length scale (see Figure 1-1).
Yada emphasized that nanotechnology is not a new field. The only truly new thing about nanotechnology, he said, is that “we have been able to capture it under a rubric called nanotechnology.” Scientists have been studying “nanoscience” phenomena for more than a century. Louis Pasteur’s work with spoilage bacteria (1866), Watson and Crick’s discovery of the structure of DNA (1953), can be considered nanoscience as well as Richard Smalley’s research on buckyballs (1996) and, in fact, each represent major milestones in the “science of small.”
Pasteur’s work with spoilage bacteria, measurable on the micrometer (μm) scale (1 μm = 1000 nanometers), led to a revolution in food processing and the development of safer, better quality foods.
Getting smaller, Watson and Crick’s discovery of the structure of DNA (a molecule of DNA is about 2.5 nm wide) led to a biotechnology revolution and the development of better biomedical treatments and agricultural production and processes.
Getting even smaller, Smalley’s research with buckyballs, which fall within the Å range (10 Å = 1 nm), marked the beginning of the current era of nanoscale science and technology and its unprecedented impacts across broad sectors of society.
Yada noted that Switzerland was the first country to invest heavily in modern nanoscience, in the mid-1990s, with Canada and other countries following suit.
Much of the recent interest in nanoscience has been driven by the development of instrumentation and the availability of tools that allow scientists to see things that they were unable to see in the past. Yada noted that when he was an undergraduate, the concept of “parts per million,” or ppm, was a “sort of wonderment.” Now, scientists talk in terms that exceed parts per trillion, because there is instrumentation that allows them to see those parts (e.g., transmission electron and atomic force microscopy, scanning tunneling X-ray). This is not surprising, Yada noted, since research often follows developments in technology. For example, most food science departments originated as dairy departments but, as processing and other techniques developed, those dairy departments transitioned into “food science” departments.
Today, much of the fascination with nanotechnology is in the area of drug delivery, with many products in phase I, II, or III clinical trial. Examples of nano-sized commercial products include paliperidone palmitate nanocrystals for the treatment of schizophrenia and paclitaxel nanoparticles for the treatment of tumors. Yada mentioned how people have imagined the notion of targeted drug delivery extending to implantable sensors and surgical robots. He quoted Helen Thomson, the author of a Fall 2008 article on nanotechnology in Trek, a magazine published by the University of British Columbia (UBC) Office of Alumni Affairs7: “Implantable sensors could allow for continuous and detailed health monitoring so illness might be detected and treated sooner. Surgical robots introduced into living tissue could excise harmful cells and repair damaged ones.” But are implantable sensors and surgical robots reality (“nano-fact’), or are they Jules Verne–style science fiction (“nano-fiction”)? Yada also referred to the movie Fantastic Voyage (a 1966 film), where a tiny submarine is injected into a person so that the crew of the submarine could perform surgery, and wondered if nanotechnology might be “where science fiction becomes reality.”
Applications of Nanotechnology in the Food Industry
Food technology experts have identified four major types of applications of nanotechnology in the food industry: (1) agriculture, (2) food processing, (3) food packaging, and (4) supplements (see Table 1-1). But this categorization, Yada explained, is somewhat arbitrary and based on ease of compartmentalization. The really interesting nanoscience, he said, is happening where these different application areas intersect. Solving these more interesting problems will require coordinated, interdisciplinary efforts among food engineers, food chemists, food microbiologists, and others. For example, taking their cues from nanomedicine, food scientists have adopted the concept of targeted drug delivery and are actively researching targeted nutrient delivery intervention strategies that could help people maintain their health. Yada commented on how this bridging of the food-medicine gap has created a common theme and led to a greater dialogue between food and nutrient scientists. He described how the Food Science department at the University of Guelph is separated from the Nutritional Science department by a delivery alleyway and that there had been very little interaction between the two departments for many years. This was true despite the fact that both departments deal with food; the only difference between them is that Food Science focuses on how that food is processed and preserved, Nutritional Science on the nutritional consequences of that food once it is inside the human body. But over the past five years or so, the two departments have begun consolidating their expertise in efforts to develop new nutrient delivery systems. While few, if any, food–related commercial applications for controlled release are available, there are a limited number of other types of nano-sized commercial products available (e.g., nanoceutials, Nutrition-be-nanotech, Aquanova) that were derived from this type of convergence of expertise (i.e., not necessarily at the University of Guelph but generally).
Yada highlighted several additional potential applications of food nanotechnology:
- Improved delivery of micronutrients and bioactive food components. He identified four major sets of challenges associated with nutrient delivery: (1) stability (i.e., against heat, pH, and oxidation during food processing), (2) taste and color (i.e., avoiding unpleasant tastes or colors), (3) safety, and (4) bioavailability. Nanotechnology could be used to address each of these. With taste, for example, while people are willing to withstand horrible tasting cough medicines, knowing that the medicines have some therapeutic value, the same is not true of foods. Moreover, consumers are becoming more discerning, wanting more palatable foods than in the past.
- Controlled release (i.e., the controlled release of bioactive compounds, such as omega-3 fatty acids). Just as in medicine, where the aim is to eliminate the potential of under- or over-dosing, the main goal of controlled release of bioactive compounds is to avoid cyclical actions and possible side effects. This has important applications for foods designed for people with diabetes, for example, where it would be desirable to maintain a steady state of glucose release.
- Product traceability. As the recent melamine threat demonstrated, the ability to trace contaminants back to their source is an important component of food safety. Yada pointed to Stephen D. Nightingale’s presentation at the 2008 Institute of Food Technologists (IFT) International Food Nanoscience Conference as a source of information on this topic.
- Food safety intervention. While Yada did not elaborate on this potential application, he showed a slide citing R.A. Latour’s work on the use of adhesin-specific nanoparticles for the re-removal of pathogenic bacteria from poultry. He mentioned that Frans Kampers would be speaking more on this topic.
- The detection of zoonotic diseases. Zoonotic diseases are a growing problem, and there are many examples of nanotechnology being applied toward prion detection in particular, as well as other food-borne toxins.
- The development of new food packaging materials, including nanocomposite polymer films. Yada referred to the development of “intelligent packaging that allows us to not only prevent some contamination from occurring or prevent its proliferation but also detects other compounds.” The classic example of this type of application, he said, is packaging that controls over-ripening and keeps bananas green or yellow for longer. “We’ve made some developments there,” he said. Other improvements being sought include packaging with better oxygen and water vapor transmission barrier properties, stronger mechanical properties, and improved thermal stability.
He then briefly described some fabrication approaches being used to construct novel nano-sized food structures and explained how these nano-scale structures add nutritional functionality and value to food. He noted that many of these fabrication approaches are being studied at the U.S. Department of Agriculture (USDA) Cooperative State Research, Education, and Extension Service (CSREES) (which operates in partnership with the 16 other federal agencies that comprise the National Nanotechnology Initiative [NNI]):
- The use of nano-scale agricultural foodstocks to develop new materials with new functionalities. Yada used corn zein as an example of a raw agricultural material being studied for its potential to serve as a nano-size building block of new food materials with added value.
- The use of milk protein nanotubes to add functionality. Yada said that “no longer will milk be that substance that we drink three times a day in a glass.” Milk is now being fractionated so that some of those fractionated components (e.g., milk protein nanotubes, casein micelles) can be used for other purposes, for example to deliver nutraceuticals.8
- The use of nanostructured fluids to develop new functionalities that have not existed in the past.
- The use of nanoemulsions (i.e., nanostructured emulsions) to serve as a platform for nutrient delivery, for example by encapsulating iron in a food product (e.g., rice) in a way that is palatable to consumers. Normally, iron forms a brown solution, which most people would find unpalatable. But nanoemulsion technology provides a way to coat rice with iron in such a way that the iron is transparent to the eye. Yada identified this technology as one that “may allow us to feed portions of the world that are deficient in certain minerals and vitamins.” Yada also pointed to the use of sugar beet pectin as a component in the microencapsulation of lipophilic food ingredients (i.e., molecules and vitamins),9 which also serves as another example of how naturally existing nano-sized agricultural foodstocks can be used in nanotechnology.
Yada mentioned the use of solid lipid nanoparticles (SLNs) as another platform of delivery and cited Dérick Rousseau’s presentation at the 2008 IFT International Food Nanoscience Conference. SLNs are nanoparticles made from solid lipids by high pressure homogenization. Added ingredients can be incorporated into the lipid matrix. Yada commented that Jochen Weiss would be describing SLNs in more detail later during this workshop see Chapter 2.
“Nanotechnology has been called a molecular revolution—innovation so profound it will allow us to rebuild our world molecule by molecule. The unprecedented benefits of such control over matter have the potential to permeate every aspect of our lives. But so do the risks.”
—Hilary Thomson, 200810
Yada began his discussion of the societal implications of nanotechnology with this quote from Thomson. He noted that while studying and developing these various applications of nanotechnology in food, there are also several issues about the consequences of nanotechnology that will need to be addressed in order to alleviate consumer concerns. For example, can nanoparticles pass the blood-brain barrier, and is this passage harmful? Does modification of natural nanoparticles in food pose a risk? What is the effect of the food matrix? What safety data will be required by global food authorities? Yada listed five sets of issues that must be addressed:
- Transparency. Many analogies have been drawn between nanotechnology and genetically modified organisms (GMOs), with many consumers worried about whether nanotechnology will be deemed harmful 5 or 10 years in the future, even if and when the science is deemed safe today. Yada described the issue as a “philosophical debate.” There is, however, an important difference between GMO and nanotechnology: There were regulations in place for the monitoring and regulation of GM foods (i.e., the same regulations that had been used to monitor and regulate foods developed through traditional breeding). There are important unanswered questions about whether the risk assessment and management systems traditionally used for chemical and microbial contamination are going to be adopted or if new ones are going to be developed. Either way, he said, “One has to remember that we probably have to adopt the same kind of framework and concerns that we would for anything else and not become alarmists in this new technology.” Many of the regulatory issues are the same as they are for any other new technology (e.g., low acceptance of risk, low profit margin, type of safety data required by food authorities globally).
- Education. Public education, especially among children, needs to improve with respect to understanding nanotechnology (as well as other technologies). Yada quoted Neal Lane, former science advisor to President Clinton: “In the beginning, an explicit aim of the U.S. National Nanotechnology Intitiative (NNI) … was to excite young girls and boys about science, particularly the physical sciences and engineering. The intent was to reach millions of children using the wonders of nanotechnology to encourage them to study science and to equip them to compete successfully at the cutting-edge of a globalized economy.” The question is: How do we teach children to be critical of the information that is so readily available right at their fingertips? Yada mentioned just having finished teaching a course where he had students believing that information available on the Internet is true, simply by virtue of it’s being on the Internet, in much the same way that past generations believed that if something was reported in the newspaper, it must be true.
- Benefits. What are the societal impacts of nanotechnology? Who will benefit, and who will pay? Yada referred to a 2003 report on the societal implications of nanotechnology published by the Nanoscale Science, Engineering and Technology (NSET) Subcommittee of the National Science and Technology Council’s Committee on Technology: www.nano.gov/nni_societal_implications.pdf. For more information on the benefits of nanotechnology, Yada also referenced a more recent Project on Emerging Nanotechnologies newsletter dedicated to the topic of nanotechnology (Nanotechnology: Energizing the Future): www.nanotechproject.org/publications/archive/nanotechnology_energizing_future/. The newsletter continues and updates a discussion on nanotechnology that took place at a 2006 meeting cosponsored by the Project on Emerging Nanotechnologies, National Institutes of Health, and the National Science Foundation (NSF).
- Consumer safety. Yada referenced the World Nanofood Report (http://www.fiweekly.com/WNR1108.pdf) and a Canadian Academies report, Small is Different: A Science Perspective on the Regulatory Challenges of the Nanoscale (http://www.scienceadvice.ca/documents/(2008_07_10)_Report_on_Nanotechnology.pdf), both of which address safety and regulatory issues surrounding the use of nanotechnology in food. The latter report addresses the issue of unknown potential hazards.
- Environmental impact. Yada quoted the Trek magazine article on nanotechnology again: “[UBC assistant professor Milind] Kandlikar says … scientists just don’t know what properties—shape, size, chemical composition or coatings—might make nanoparticles and nanowaste hazardous.” He referred workshop participants to a website describing activities of a recently developed center, jointly run by Duke University and University of California, Los Angeles, and funded by NSF and the U.S. Environmental Protection Agency (EPA), for examining the potential hazards of nanomaterials: www.cenonline.org.
In conclusion, Yada again quoted the Trek magazine article: “Nanotechnology could be the first technology developed with sensitivity to ethical, environmental and social issues. If we fearlessly and responsibly examine all aspects of the technology today, we can anticipate our tomorrow will be enriched with benefits.” He said that the benefits of nanotechnology are enormous, with many potential and exciting products on the market. But so too are the challenges. There are major gaps in our understanding of the health, safety, environmental, and societal impacts of nanotechnology. Filling these gaps will be critically important to the long-term success of nanotechnology.
Finally, Yada reemphasized that food nanoscience represents a university research culture shift and that filling these gaps will require a multidisciplinary approach, and he stressed the importance of building public trust in the science and industry of nanotechnology. Controversial issues surrounding nanotechnology have already sparked public interest in the field. Establishing public trust and developing and maintaining the credibility of nanoscience will require a coherent and rational approach on behalf of the scientific enterprise, careful planning and strategic coordination, and the bringing together of the necessary multidisciplinary team with a networking mindset.
This section is a paraphrased summary of Rickey Yada’s introductory presentation.
Rickey Yada, PhD, is a Professor of Food Science and a Canada Research Chair in Food Protein Structure at the University of Guelph, Ontario.
Available online at http://plan2005
.cancer.gov/glossary.html. Accessed January 19, 2009.
Available online at http://www
.ccrnp.ncifcrf .gov/~toms/glossary.html. Accessed January 19, 2009.
Available online at http://www
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This image is a slight modification of “The Scale of Things” chart developed by the Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy. The original can be viewed online at http://www
H Thomson. 2008. Is nanotechnology the next big thing or the next big nightmare? Trek Fall:15–17.
E.g., see E Semo, E Kesselman, D Danino, and YD Livney. 2007. Casein micelle as a natural nano-capsular vehicle for nutraceuticals. Food Hydrocolloids 21:936–942.
E.g., see S Drusch. 2007. Sugar beet pectin: A novel emulsifying wall component for microencapsulation of lipophilic food ingredients by spray-drying. Food Hydrocolloids 2:1223–1228.
H Thomson. 2008. Is nanotechnology the next big thing or the next big nightmare? Trek Fall:15–17.
National Academies Press (US), Washington (DC)
Institute of Medicine (US) Food Forum. Nanotechnology in Food Products: Workshop Summary. Washington (DC): National Academies Press (US); 2009. 1, Introduction.