Presented By

Flora-Glad Chizoba Ekezie

NANOTECHNOLOGY IN THE FOOD INDUSTRY

Outline Introduction History of Nanotechnology Approaches to Nanotechnology. Types of Nanomaterials and Nanostructures Regulation Conclusion References

INTRODUCTION

Nanoscience Study of Phenomena and manipulation of materials at atomic, molecular and

macromolecular scale and macromolecular scales. Here, properties differ significantly from those at larger scale.

(Michael, 2004)

Nanotechnology Involves the characterization, fabrication and/or manipulation of structures,

devices or materials that have at least dimension approximately 1- 100nm in size.

(Duncan, 2011)

Contd…

While many definitions for nanotechnology exist, the National Nanotechnology Initiative calls it “nanotechnology” only, if it involves all of the following:

1) Research and technology development at the atomic, molecular or macromolecular levels, in the length scale of approximately 1-100 nanometer range.

2) Creating and using structures, devices and systems that have novel properties and functions because of their small and/or intermediate size.

3) Ability to control or manipulate on the atomic scale.

Scale in Relation to Food Structure

HISTORY OF NANOTECHNOLOGY

FATHER OF NANOTECHNOLOGY Richard Feynman

“There’s plenty room at the bottom”December 29, 1959

Nobel Prize in Physics, 1965

Contd… 1974, Nario Taniguchi uses the term “Nanotechnology”

1985, Buckyball discovered. (Harry Koto won 1996 Nobel prize in chemistry along with Richard Smalley and Robert Curl.

1986, K. Eric Drexler developed and popularized the concept of Nanotechnology and founded the field Molecular Nanotechnology.

Approaches to NanotechnologyThere are two approaches of nanotechnology applications:

1) Top-Down Approach: Involves processes such as cutting, carving. The approach entails taking a chuck of material and removing chucks of it. E.g. By grinding or by dissolving with acids until final product is achieved.

2) Bottom-up Approach: Involves building complex systems by combining small atomic-level components. It starts with constituent often gases or liquid and uses chemical, electrical or physical forces to build a nanomaterial atom by atom or molecule by molecule.

Types of Nanomaterials and nanostructures

There are different nanomaterials, produced by the two approaches and peculiar benefits to the Food industry. Of particular interest are engineered nanoparticles (ENPs). The various types of ENPs include:

A. Inorganic nanomaterials:

These include ENMs of transition metals such as silver, iron; alkaline earth metals such as calcium and magnesium; and non-metals such as selenium and silicates.

Other ENMs include titanium oxide, zinc and copper oxide. Their application in the food industry are majorly in packaging were characteristic such as U.V protection, mechanical strength, surface coating and processing aid, is utilized.

Contd…B. Surface Functionalized nanomaterials

Surface functionalized nanomaterials are the second-generation ENMs that add certain types of functionality to the matrix such as antimicrobial, antioxidant or a preservative action.

They are used to bind to polymer matrix to offer mechanical strength or a barrier to movement of gases. They are more likely to react with different food components or became bound to food matrices.

A typical example is functionalized nano-clays in food packaging to develop materials with enhanced gas barrier properties.

Contd…C. Organic nanomaterials

These include substances encapsulated in nano-delivery systems. Examples include vitamins, antioxidants, colours, flavours and preservatives.

The main principle behind the development of nano-sized organic substances is their increased uptake, absorption and improved bioavailability in the body, compared with conventional bulk equivalents.

An example of an organic nanomaterial is the tomato carotenoid lycopene.

Canola active oil is an Israel product Technology which is a development of minute compressed micelles that allows penetration of healthy components that are insoluble in water or fat.

Types of NanostructuresA. Nanoencapsulation It is defined as a technology used to pack substances in miniature, making use

of techniques such as nanocomposites, nanoemulsification and provide final product functionality that include controlled release of the core.

Examples includes bioactive compounds such as vitamins, antioxidants, protein and lipids as well as carbohydrates.

The main advantage is said to be better dispensability of water insoluble additives in foodstuffs without the use of additional fats or surfactants and also enhanced tastes and flavours.

Contd..B. Nanoemulsion They are a class of extremely small droplets in the range of 50 to 100nm that

appear transparent or translucent. They contain the continuous phase, dispersed phase and surfactant.

The nanosizes of emulsions enhance not only stability of the emulsion but also the bioavailability of the encapsulated phytochemicals.

Applications include decontamination of packaging equipment, removal of pesticide residues from fruits and vegetables, removal of oil and dirt from cutlery, inclusion in berages e.t.c

Contd…C. Nanocomposites These are materials in which filler has at least one dimension smaller than

100nm. Nanocomposites can improve mechanical strength; reduce weight; increase heat resistance and improve barrier against oxygen, carbon dioxide e.t.c.

The various types include a) Polymer nanocomposites which are thermoplastic polymers that have nanoscale inclusions, 2-8 % by weight e.g. Nano-clay, carbon nanoparticles, nanoscale metals e.t.c.

And b) Bio-based nanocomposites in which plant materials ( starch, cellulose, proteins other polysaccharides e.t.c) are used. However they have poor mechanical and barrier properties but can be augmented by incorporating inorganic nanoparticles. E.g. Bayer polymers contain silicate nanoparticles.

Contd…D. Nanotube Carbon Nanotubes (also known as buckytubes) are allotropes of carbon with a

cylindrical nanostructure. They are members of the fullerene structural family, which also includes these spehrical buckyballs.

Nanotubes can be categorized as single-walled nanotubes (SWNTs) and multi-walled nanotubes (MWNTs).

Major application area of application in the food industry is packaging.

USES OF NANOTECHNOLOG

Y IN THE FOOD INDUSTRY

Food Packaging Applications Food packaging is considered to be one of the earliest commercial applications

of nanotechnology in the food sector.

About 400-500 nano-packaging products are estimated to be in commercial use at the moment, while nanotechnology is predicted to be used in the manufacture of 25% of all food packaging within the next decade.

1. Polymer nanocomposites

Incorporating nanomaterials into the packaging polymer to improve physical performance, durability, barrier properties and

biodegradation ( Bradley, 2011).

Polymer matrix + Nanomaterials = PNCs

Polymers used in Food packaging

1. Polyolefins Polypropylene (PP) Polyethylene (HDPE, LDPE,

e.t.c.

2. Polyethlene terephthalate(PET)

3. Polystyrene(PS)

4. Polyvinyl chloride (PVC)

Strength and stiffness

Barrier to oxygen and moisture

Resistance to food component attack

Flexibility

Contd…

PET provides a good barrier to oxygen (O2 permeability = 6-8 nmol/m1s1 GPa1) but highly permeable for water vapour.

Density polyethylene (HDPE) fares much worse (O2 permeability = 2000-4000 nmol/m1 s1 GPa1) but HDPE offers a significantly better barrier properties agasint water vapor than PET.

In some applications, high barriers to migration or gas diffusion are undesirable (E.g. fresh fruits and vegetables)

High oxygen and carbon dioxide barriers is necessary (E.G. Plastics utilized for carbonated beverages containers).

(Finnigan et al., 2009)

Advantages of Polymer based nanocomposites

1. Enhanced polymer barrier properties2. Stronger

3. More flame resistant4. Possess better thermal properties e.g Melting point, degradation and glass

transition temperature.5. Alteration in surface wettability and hydrophobicity.

2. Nanocoatings Incorporating nanomaterials onto the packaging surface (either the inside or the

outside surface, or a sandwitched as a layer in a laminate) to improve especially the barrier properties.

Using nano-thin coatings (Polymer + nanoparticles ) can help improve enhanced barrier performance.

Vaccum-deposited aluminium coatings on plastic films

Coating of the surfaces of glass food and beverages containers (Bottles, jars) with organosilicates.

Example: Nanosilica coated high oxygen barrier films

Advantages

Excellent oxygen and moisture barrier.

Shelf life of packaged food increase and hence, production cost reduces.

Aroma preservation

Good printability and laminating machinability.

Transparent and Eco-friendly.

Time invariant transparency

Excellent mechanical and optical property.

3. Surface Biocides Incorporating nanomaterials with antimicrobial properties on the surface of the

packaging material.

Used to maintain hygienic condition of the food contact surface by preventing or reducing microbial growth and helping cleanability.

Common in some reusable food containers such as boxes and crates and inside liners of refrigerators and freezers also.

Have a high ratio of surface area to mass

Chemicals commonly used are Nanosilver, zinc, magnesium and titanum dioxide.

Antimicrobial activity of nanoparticles

Their activity is related to several mechanism:

1. Directly interact with the microbial cells:a. Interpreting trans-membrane electron transferb. Disrupting/penetrating the cell envelopec. Oxidizing cell components

2. By producing secondary metabolitesa. Reactive oxygen species (ROS)b. Dissolved heavy metal ions.

(Li et al., 2008)

4. Active Nano-packaging Incorporating nanomaterials with antimicrobial or other properties (e.g antioxidant) with

intentional release into and consequent effect on the package d food. Examples: Examples include:

1. Antimicrobial agents like AgNps, magnesium oxide, copper and copper oxide, zinc oxide, calcium selenide/telluride, chitosan and carbon nano-tubes are used.

Ultrasonically dispersed TiO2 nanoparticles throughout EVOH films and observed their effective photoactivated biocidal properties against microorganisms (bacteria and yeasts).

AgNPs being incorporated into cellulose pads for use in modified atmosphere packaging.

2) Oxygen Scavenging materials

Food deterioration by indirect action of O2 includes food spoilage by aerobic microorganisms.

Contd..

Oxygen scavenger films were successfully developed by Xiao et al ., 2004 by adding titanium Nps to different polymers.

Iron-based nanoclay with LDPE, HDPE, PET

5. Intelligent packaging Incorporating nano-sensors to monitor and report on the condition of the

food.

They are able to respond to environmental changes inside the package (Temperature, humidity and level of oxygen exposure)

Nano-sensors communicate the degradation of product or microbial contamination (Bouwmeester et al., 2009)

Also give the history of storage and period of storage. Nano-sensors can detect certain chemical compounds, pathogens and toxins in food.

Eliminate the need for inaccurate expiration dates.

Provide real-time status of Food freshness e.g Ripesense, onvu

Examples of Nanosensors in Packaging

1. Noninvasive gas sensors (Mill et al., 2005) Photo-activated indicator ink for in-package oxygen detection based upon

Nanosized TiO2 and SnO2 particles and a redox-active dye(methylene blue).

2. Sensors for moisture content (Luechinger et al., 2007) Based upon carbon coated copper nanoparticles dispersed in a tenside film.

3. Carbon dioxide content in MAPs (McEboy et al., 2002) Based upon analysis of luminescent dyes standardized by flourophore

encapsulated polymer nanoparticles.

6. Bio-plastics Biodegrable polymers which meet all criteria of scientifically recognized norms for

biodegradability and compostability.

Renewable biomass source such as vegetable oil, corn-starch, potato-starch or microbes, rather than fossil fuel plastics which are derived from petroleum.

AdvantagesIncrease the gas and vapour barrier properties

Better degradability

Increase the mechanical strength

Efficient antioxidant, oxygen scavenging or antimicrobial bio packaging

Increase foods quality and safety.

APPLICATON OF NANOTECHNOLOGY IN FOOD PROCESSING

During food processing, nanoparticles have been applied to improve nutritional quality, flow properties, flavor, color and stability or to increase shelf life.

Indeed, nanotechnology might help in development of healthier food with lower fat, sugar and salts to overcome many food-related diseases.

Recently, bulk amounts of SiO2 and TiO2 oxides have been permitted as food additives (E551 and E171,respectively) (EFSA, 2000).

Effective olive oil hydrolysis by the use of covalent immobilization of porcine triacylglycerol lipase onto functionalized nanoscale SiO2 with reactive aldehyde group for better reuse, adaptation and stability have also been reported (Bai et al., 2006).

Several nano and micro-structured assemblies of nanoparticles have bee designed for encapsulation of food ingredients, additives, nutritional supplements as well as functional foods (Augustin and Hemar, 2009).

Contd.. Interactive foods and beverages give desired flavors ad colours (on-demand

delivery) by the addition of Nano capsules which burst at different microwave frequencies.

U.S nanotechnology center has explored the application of nanotechnology for water purification and treatment focusing on membrane and membrane processes.

Nanotubes made of milk protein by self-assembly have potential to be used as novel ingredients for viscofying, gelation and nanoencapsulation controlled release.

Applicationf of Nanotechnology in Nutraceutical Delivery

The potential of nanotechnology in functional food, design of nutritional supplements and nutraceuticals containing nanosized ingredients and additives such as; vitamins, antimicrobials, antioxidants, and preservatives are currently available for enhanced taste, absorption and bioavailability (Momin et al., 2013).

Some nutraceuticals incorporated in the carriers include lycopene, beta-carotenes and phytosterols are used in healthy foods to prevent the accumulation of cholesterol (Mozafari et al., 2006).

Whey proteins nanospheres(40nm), which are internalized by cells and degraded therein to release the nutraceutical compounds, can be used as carriers for oral administration of nutraceutical agents to improve their bioavailability.

Application of Nanotechnology in Food Microbiology and Food Safety

Detection of very small amounts of chemical contaminants, viruses and bacteria is another application of nanotechnology.

Food pathogens can be detected using nano-flourescent particles manufactured out of magnetic materials .

Chip based sensing is another new area for rapid detection of biological pathogens with tremendous potential in early warning regarding exposure to air and pathogens.

The biosensors can be incorporated to alert consumers, producers and distributors against safety status of the processing product.

Barcode detection using Nanoparticles

Examples of foods, food packaging and agriculture products that contain nanomaterials

Conclusion

Nanotechnology, nano-science and nano-biotechnology are concerned with the understanding and rational manipulation of materials at the atomic and molecular levels.

In its widest sense, nanotechnology is a natural part of food processing and conventional foods because the characteristic properties of many foods rely on nanometre sized components.

As developments in nanotechnology continue to emerge, its applicability to the food industry will increase potentially.

References Buonocore, G. G., Conte, A., Corbo, M. R., Sinigaglia, M., & Del Nobile., M. A.

(2005). Mono- and multilayer active films containing lysozyme as antimicrobial agent. Innovative Food Science and Emerging Technologies, 6, 459–464.

Burdo, O. (2005). Nanoscale effects in food production technologies. Journal of Engineering Physics and Thermophysics, 78(1), 90–97.

Chaudhry, Q., Scotter, M., Blackburn, J., Ross, B., Boxall, A., Castle, L., et al. (2008). Applications and implications of nanotechnologies for the food sector. Food Additives and Contaminants, 25(3), 241–258.

Fernandez, A., Torres-Giner, S., & Lagaron, J. M. (2009). Novel route to stabilization of bioactive antioxidants by encapsulation in electrospun fibers of zein prolamine. Food Hydrocolloids, 23(5),1427–1432.

Neethirajan, S., & Jayas, D. S. (2007). Sensors for grain storage. In: 2007 ASABE Annual International Meeting, 17-20 June 2007, Minneapolis, USA.