ISSUE THIRTEEN AUGUST 2009 ISSN 1757-2517
THE MAGAZINE FOR SMALL SCIENCE Nanotechnology for the Food Industry Huge potential market - what’s the risk?
Regulating Nanotechnology in Food A flavour of current issues
Nanosensors Low power, low cost, high sensitivity
Interview: Frans Kampers A vision of personalised food
Countryprofile: Nordic Nano Small is beautiful - and can be world class
Heat-Buffering Packaging Keeping perishables fresh
Why Should We Worry? Nanotechnology in food & agriculture
Nanotechnology: The 21st century catalyst for sustainability?
What’s New in Nano? Keep up with the latest news
NANOTECHNOLOGY IN FOOD AND DRINK Opportunities and Challenges PLUS: NANO IN SUNSCREENS: WHAT’S SAFE AND WHAT’S NOT
TS N E NT O C
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In the next issue - due out 1st October 2009: Nanomaterials, Nanotechnology in the UK, Encapsulation, Tissue Engineering, Robotics, Molecular Machines Plus: What’s new in nano… and lots more!
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nano Issue 13, August 2009
Managing Director: Ottilia Saxl ottilia.saxl@nanomagazine.co.uk Editor: Elaine Mulcahy elaine.mulcahy@nanomagazine.co.uk Assistant Editor: Tina Hoermann tina.hoermann@nanomagazine.co.uk Sales and marketing assistant: Jana Perlet jana.perlet@nanomagazine.co.uk Design: Different Voice www.differentvoice.co.uk Website design: Tim Spencer tim.spencer@nanomagazine.co.uk Contact Advertising: jana.perlet@nanomagazine.co.uk Subscriptions: subs@nanomagazine.co.uk +44 (0)1786 447520 Contributors Kathy Groves & Dr Pretima Titoria, Leatherhead Food Research; Douglas Robinson, Institute of Nanotechnology; Heidi Hautajarvi, British Embassy Stockholm; Markus Lindberg, Nano Connect Scandinavia; Barry Park and Sian Bronock, Oxonica; Frans Kampers, BioNT Wageningen, Tiju Joseph, Sensors & Instrumentation KTN; Jim Johnston, Victoria University of Wellington; Sarah Haeuser & Jurek Vengels, Friends of the Earth Germany; John F. Elter, University at Albany in Albany; Frans Holthuysen, Philips Research Laboratories Miplaza Philips Research Europe.
©2009 ION Publishing Ltd 6 The Alpha Centre, Stirling University Innovation Park Stirling FK9 4NF Scotland Article contributions to NANO magazine come from a range of sources and while we always strive to ensure accuracy in reporting, NANO accepts no responsibility for inaccuracies that may arise. The views of contributors do not necessarily reflect the views of NANO magazine or IoN Publishing Ltd.
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FEATURES Nanotechnology for the Food Industry ................................012 Huge potential - what’s the risk? Regulating Nanotechnology
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in Food ...................................................016
039 COMMENT
A Flavour of Current Issues
Why Should We Worry? ......................034 Nanotech in Food & Agriculture
Nano in Suncreens ..............................026
INTERVIEW
What’s safe and what’s not
028 Heat-buffering Packaging..................031 Keeping perishables fresh
REGULARS Editorial.................................................004 Events ....................................................006 What’s new in nano .............................008 Nanoart..................................................042
Nanosensors.........................................036 Low power, low cost, high sensitivity Nanotechnology ..................................039
Frans Kampers .....................................028 Talks about his vision for personalised food
031
The 21st Century Catalyst for Sustainability?
COUNTRY PROFILE Nordic Nano: Nanotech in Denmark and Sweden.........................019 Small can be world class
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034 003
E UR T A FE
Nanotechnology for the Food Industry THE POTENTIAL FOR NANOTECHNOLOGY TO IMPROVE ALL ASPECTS OF LIFE HAS GENERATED HUGE INTEREST, AS WELL AS CONCERNS. APPLICATIONS IN THE FOOD & DRINK INDUSTRY ARE MUCH LESS DEVELOPED THAN FOR OTHER AREAS BUT IT IS ANTICIPATED THAT THESE WILL GROW RAPIDLY. KATHY GROVES AND DR PRETIMA TITORIA REPORT.
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◊nano ccording to the Helmut Kaiser Consultancy, the nanofood market has increased from a value of USD2.6 bn in 2003 to USD5.3 bn in 2005; and it is expected to soar to USD20.4 bn in 2015. This trend is a clear indication that nanotechnology will progress within the food & drink industry, and all companies, should they wish not to lose out, need to stay on top of this dynamic development.
A
Indeed “nanotechnologies” is probably more of a correct term to use these days, as there are such a wide span of different nano technologies and applications. “Nano-technologies” is crossing many technology boundaries as the scientists from disciplines such as chemistry, physics and other pure sciences to medical, materials, sensors and food to name a few, interact to link their researches together. Developments in the food and drink areas are at a at very early stage and are currently being shaped by progress in other areas, most specifically the pharmaceutical industry. Currently the main uses for nanotechnologies in food & drink applications are in packaging and in the health/nutraceutical supplements areas, and it is expected that the use of nanotechnologies will not only increase within these two areas in the immediate future, but will also expand into other areas, such as ingredient functionality, emulsions and sensors. Examples in packaging An example for the packaging industry is the use of nano-silver. Because of its antimicrobial properties, nano-silver has been used to coat packaging materials and inner surfaces of fridges and dishwashers, as well as being incorporated into plastic food containers. Another example is the use of nanoclays, which can be incorporated into plastic bottles for drinks – preventing oxygen from migrating through the plastic bottle walls and destabilising the drink and therefore extending the product shelf life. With respect to the health supplement areas, the use of nano-sized droplets has been found to increase the efficacy of certain nutraceuticals or health agents. These are generally prepared either by emulsion technology or by micelle encapsulation technology. For example, the antiinflammatory properties of curcumin were found to be enhanced if the emulsion droplet size was reduced below 100nm (Wang et al, 2008, Food Chemistry, Vol 108: 20). Nano-encapsulation is reported to improve solubility properties and enhance bioavailability, and an example is the Canola Active Oil, produced by Shemen
Industries; this oil product contains nanocapsules or nanomicelles of phytosterols, which are thought to reduce the uptake of cholesterol from the digestive system. Nanofoods While the use and benefits of nanotechnologies is extolled in published research / academic papers, there has been some technology transfer into real food and drinks products. A database of all commercial products claiming to use nanotechnology can be found by accessing the website set up by the Project on Emerging Nano-technologies (“PEN”) organisation, which is based in the USA. Within the website -www.nanotech project.org - there are six inventories, and one of these is specifically set up for the food & drink industry. A cooking oil and chocolate shake are some of the products listed. The chocolate slim shake is a dietary product, where silica nano-particles are included that are coated with cocoa particles to give a creamy chocolate taste with reduced fat content. There have been some concerns about the use and safety of “nanofoods”. However, it is important to recognise that the term nano-particles includes normally ingested material and also particles that do not usually form part of the diet, and there is a strong argument that these latter nanoparticles should be addressed with different concerns. The application of nanotechnologies to standard ingredients such as salt, fat and biopolymers to produce foods with improved properties should not pose any danger as it is thought that they will be broken down in the body in the usual way. This needs to be emphasised to the media and consumers, so that the development of new foods benefiting from nanotechnologies can proceed. Examples of inorganic nanoparticles that could be a risk include silver, titanium and silica, and the main concern is that these are not normally eaten and metabolised. Thus, it is certainly sensible for the food & drink industry to look at the use and safety of these inorganic nanoparticles. The use of silica nanoparticles as centres for diet products, such as the commercial Chocolate SlimShake, has raised the question as to whether and how these products should be regulated. All foods, whether natural or processed, contain nano-particles. Examples of natural products that contain nano-
particles include milk and meat. Milk contains caseins, a form of milk protein present at the nanoscale, and meat is made up of protein filaments that are much less than 100nm thin. The organisation and change to the structures of these affects the texture and properties of the milk or meat. Examples of products that contain nanoparticles resulting from the manufacturing processes include margarines, toffees, chocolate and cheese. For example, toffee is made up of fat droplets surrounded by a thin nanoscale protein membrane in a matrix of sugar containing milk protein. The stability of the interface is important, as it controls the fat droplet size and hence the sensory properties, such as texture and creaminess. Understanding how the properties of foods change with size of the ingredients and then manufacturing foods with controlled size and structure, should allow improvements to properties that are of benefit to the consumer. In addition, this approach allows for development of healthier foods, which is of concern to the Western world where many suffer from obesity and related diseases, such as high blood pressure, diabetes and coronary heart disease. The use of nanotechnologies can lead to the development of products that are lower in fat, sugar and salt, and can help overcome technical and sensory problems that food developers come across when using conventional methods. An example is the development of lower fat foods that taste as good as the higher fat products. Using technology to put nanosized water droplets inside fat droplets which are then inside a continuous water phase (a water in oil in water (WOW) system) can produce mayonnaise that is much lower in fat but tastes as good as the high fat product. Figure 1 shows an image of a WOW emulsion under the microscope, where the fat is white and the water black. Another example is the particle size reduction of salt crystals. There is a strong move from government agencies to lower the amount of salt in the consumer’s diet as the current intake is considered too high and dangerous for health. Studies at Leatherhead Food International have shown that the size of salt particles dominates the salt intensity and how quickly the salt is tasted. Smaller (micro-sized) salt particles were found to be tasted faster and with higher intensity than standard sized table salt. This observation is due to the increase in surface area giving a change in properties. By using smaller, and potentially nano-sized, salt particles, the level of salt in products such as crisps and snacks could be reduced, giving a healthier product.
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E UR T A FE
Fig 1 Water in oil in water emulsion by confocal
Fig 2 Salt grains on the surface of a potato chip by scanning electron microscopy
scanning laser microscopy
For example, Figure 2 shows the surface of a potato chip with table salt added as usual by the consumer. The relatively large size of the salt grains can be seen. If the size was reduced, more grains would cover the surface of the chip. With increased saltiness and increased coverage, the consumer would not need to add as much salt to this type of product. However, there is further research needed to understand and optimise the best size for use and to overcome technical difficulties, before this technology can be fully used. It is anticipated that food ingredients, when reduced to less than 100nm, will have different properties. Active research in this aspect is required and is predicted to bring in enormous benefits to both food manufacturers and consumers. In addition to the above-mentioned benefits, the possibility of removing some of the additives in foods could be achieved, therefore giving products a clean label. Another key driver for the food industry that needs to be mentioned here is the one of food safety. Increasing food safety is partly achieved by the use of antimicrobial surfaces both in packaging and on food preparation surfaces. Additionally new developments in sensor technology will allow advances in analysis to give rapid accurate assays for bacteria, viruses and so on in foods. However, there must be in parallel to the above research, a study that looks at instrumental techniques for objective, reliable and reproducible measurements of nanoparticles. This is crucial, as this will determine the wordings and the definitions that will appear in the regulatory world, and will allow a true picture of the presence and safety of nanoparticles in foods.
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THERE HAVE BEEN SOME CONCERNS ABOUT THE USE AND SAFETY OF “NANOFOODS”. HOWEVER, IT IS IMPORTANT TO RECOGNISE THAT NANO-PARTICLES INCLUDES NORMALLY INGESTED MATERIAL AND ALSO PARTICLES THAT DO NOT USUALLY FORM PART OF THE DIET, AND THERE IS A STRONG ARGUMENT THAT THESE NANO-PARTICLES SHOULD BE ADDRESSED WITH DIFFERENT CONCERNS. As a means of informing the food & drink industry of the rapid and relevant progress made with respect to nanotechnologies, Leatherhead Food Research has set up a Working Group, NanoWatch©. Advances in the non-food and food areas, which are announced through scientific publications and patents, are summarised and reported to NanoWatch©’s members. In addition, small feasibility or proof-of-principle trials are carried out to evaluate the practicality of using emerging technologies in the food & drink industry. Within the current membership, preparation of stable nanoemulsions, utilisation of self assembly technology and assessment of different instrumental techniques in measurements of nano-particles are being investigated. Separately from this, Leatherhead Food Research has with the Nanotechnology Knowledge Transfer Network (NanoKTN) formed a LFR-NanoKTN Food Focus Group. This Group allows the members to put forward their views to government and regulatory bodies as well as bid for grants to further the benefits of nanotechnologies in the food application areas. Further information on the NanoWatch©.Working Group and the LFR-NanoKTN Food Focus Group can be obtained from the authors. n
Dr. Pretima Titoria is Project Manager – Ingredients, in the Ingredients & Product Innovation Group at Leatherhead Food Research. In addition, Pretima is the Forum Liaison Officer for the Food Ingredients Forum at Leatherhead, which conducts research projects on the behalf of Leatherhead’s Members. Kathy Groves manages the microscopy section within Food Innovation. She is one of the key managers of the nanotechnology working group at Leatherhead and a Fellow of the Royal Microscopical Society and a member of the Board of the Food Structure & Functionality division of the Association of Oil Chemists Society Contact Leatherhead Food Research Randalls Road, Leatherhead Surrey KT22 7RY kgroves@leatherheadfood.com ptitoria@leatherheadfood.com