Glacier Journal of Scientific Research ISSN:2349-8498
Total Page:16
File Type:pdf, Size:1020Kb
Glacier Journal Of Scientific Research ISSN:2349-8498
Nanotechnology : An advanced way to Meat Processing and Packaging
Lokesh Tak , Sanjay Singh, Basant Bais* , Anurag Pandey , Arun Soni , Pramod Kumar Singh Department of Livestock Product Technology, CVAS, RAJUVAS, Bikaner
( *[email protected], Professor and Head, LPT, CVAS, RAJUVAS, Bikaner)
ABSTRACT
The review paper focuses the evolution of nanoscience and nanotechnologies from the global perspective and their potential application in food systems including meat processing. Growing demand for sustainable production, increasing competition and consideration of health concerns have led the meat industries on a path to innovation. Nanoscience refers to components properties at nanoscale and nanotechnology refers to process or processes used in the manufacture and/or biofabrication of new materials measured at nanoscale. Nanotechnology offers a wide range of opportunities for the development of innovative products and applications in food system. Functional foods, nutraceuticals, bioactives, etc. are very recent example of it. Nanotechnology and nanomaterials are a natural part of food processing and conventional foods, because the characteristic properties of many foods rely on nanometer sized components. Meat industries across the world are focusing on the development of novel meat products and processes to meet consumer demand. Hence, a process innovation, like nanotechnology, can have a significant impact on the meat processing industry through the development of not only novel functional meat products, but also novel packaging for the products. The potential benefits of utilizing nanomaterials in food are improved bioavailability, antimicrobial effects, enhanced sensory acceptance and targeted delivery of bioactive compounds. However, challenges exist in the application of nanomaterials due to knowledge gaps in the production of ingredients such as nanopowders, stability of delivery systems in meat products and health risks caused by the same properties which also offer the benefits. For the success of nanotechnology in meat products, challenges in public acceptance, economics and the regulation of food processed with nanomaterials which may have the potential to persist, accumulate and lead to toxicity need to be addressed.
Keywords: Nanotechnology, Nanomaterials, Meat Products, nanofoods, innovative products, bioactive molecules
INTRODUCTION
Nanotechnology- the future of the world. Nanotechnology is a find that turned the world around. A new era was born after the discovery of nanotechnology. Nanotechnology is the engineering of functional systems at the molecular scale. This covers both current work and concepts that are more advanced.In its original sense, 'nanotechnology' refers to the projected ability to construct items from the bottom up, using techniques and tools
June2015,Issue Page 1 being developed today to make complete, high performance products. Today, the word nanotechnology means something a bit different. Instead of building microscopic motors and computers, researchers are interested in building superior machines atom by atom. Nanotech means that each atom of a machine is a functioning structure on its own, but when combined with other structures, these atoms work together to fulfill a larger purpose. The Council of Scientific and Industrial Research, also known as CSIR has set up 38 laboratories in India dedicated to research in Nanotechnology. This technology will be used in diagnostic kits, improved water filters and sensors and drug delivery. The research is being conducted on using it to reduce pollution emitted by the vehicles. Looking at the progressive prospects of Nanotechnology in India, Nanobiosym Inc., a US-based leading nanotechnology firm has also planning to set up India’s first integrated nanotechnology and biomedicine technology park in Himachal Pradesh. Nanotechnology has certainly acquired an essential position in the Indian Economy and Scientific Research Department and it is expected to reach the pinnacle of Development thereby making India a role model for the countries of the world.As nanotech continues to develop, consumers will see it being used for several different purposes. This technology may be used in energy production, medicine, and electronics, as well as other commercial uses. Many believe that this technology will also be used militarily. Nanotechnology will make it possible to build more advanced weapons and surveillance devices. While these uses are not yet possible, many researchers believe that it is only a matter of time.With consumers demanding higher quality meat products at affordable prices and growing competition, the meat production sector has witnessed an exceptional change in not only the ingredients, but also the processing system (Weiss et al., 2010).
Thus, expectations have risen regarding the use of ingredients and additives with improved functionality to enhance the quality and image of muscle foods (Olmedilla- Alonso et al., 2013). Some of the most commonly used additives in meat and poultry are antioxidants (e.g., butylated hydroxytoluene [BHT], butylated hydroxyanisole [BHA] and tocopherols), binders (e.g., carrageenan, sodium caseinate), thickeners (e.g., gelatin), humectants (e.g., sodium salt, glycerine), curing agents (sodium erythorbate, sodium nitrite and nitrate), flavor enhancers (e.g., monosodium glutamate), tenderizing enzymes (bromelin, ficin and papain) and sweeteners (e.g., corn syrup) (USDA, 2008). Nanotechnology can be utilized to improve the stability of such micronutrients not only during processing but storage and distribution, as well. . It is also expected that novel products developed with new ingredients and processing systems should possess similar gustatory, visual and aromatic effects as traditional meat products (Weiss et al., 2010). Nanotechnology can be referred to as an area of science and technology focused on the manufacture of nano-sized materials (less than 100 nm in diameter at least one dimension) that possess unique and novel properties, although a globally accepted definition does not exist .It also refers to the production, characterization, and manipulation of such materials (Weiss et al., 2006). The major differences between nanomaterials and bulk materials are the changes in physicochemical (e.g., porosity), optical, mechanical and catalytic properties. Other differences are also observed in the strength, absorption, function, weight, and stabilization of materials (Cockburn et al.,
June2015,Issue Page 2 Glacier Journal Of Scientific Research ISSN:2349-8498
2012). All of these properties make nanotechnology very promising, and have led to the development of many innovations in the area of food packaging (Sozer and Kokini, 2009). Nevertheless, due to the novel properties exhibited by nanomaterials, significant beneficial changes are expected to be enabled in the production, packaging and distribution of many food products, including meat products (Weiss et al., 2006). On the other hand, this novel technology may also have the potential to cause risks to human health and the environment due to the same properties which offered its benefits . The perception of such risks and benefits may influence the acceptance to consumers of using this technology (Troy and Kerry, 2010). This review focuses on the types of nanomaterials, delivery systems and the risks associated with nanomaterials in areas of meat processing and packaging.
NANOSTRUCTURES / NANOMATERIALS
Nanostructures are materials that, in at least one dimension, measure approximately 1- 100 nm. Nanostructures or nanomaterials exhibit properties different from their macroscale counterparts (their “big brothers”) such as mechanical strength (how hard they are to break), electrical conductivity (how fast electrons flow through them), thermal conductivity (how fast heat flows through them), chemical reactivity (how well/fast they react with other chemicals), transparency (how well you can see through them) and magnetism (whether or not they are magnetic). Discoveries in nanotechnology are beginning to impact the food industry and associated industries. This affects important aspects from food safety to the molecular synthesis of new food products and ingredients [Chen et al. 2006]. Range of sizes of nanomaterials in the food sector and their relative position on nanoscale/microscopic scale are listed below. Structures Diameter or length, nm DNA 12 Glucose 21-75 Liposome 30-10 000 LDH 40-300 Amylopectin 44-200 Casein micelle 60-300 Zein 200 Nanosensors <1000
SECTORAL EXAMPLE: FOOD AND AGRICULTURE
Nanotechnology is rapidly converging with biotech and information technology to radically change food and agricultural systems. Over the next two decades, the impacts of nano-scale convergence on farmers and food could even exceed that of farm mechanisation or of the Green Revolution according to some sources such as the ETC group24. Food and nutrition products containing nano-scale additives are already commercially available. Likewise, a number of pesticides formulated at the nano-scale are on the market and have been released in the environment. According to Helmut Kaiser Consultancy, some 200 transnational food companies are currently investing in
June2015,Issue Page 3 nanotech and are on their way to commercialising products25. The US leads, followed by Japan and China. HKC expects the nanofood market to surge from $2.6 billion in 2003 to $7.0 billion in 2006 and to $20.4 billion in 2010. Companies not associated with food production in the public mind are already supplying nano-enabled ingredients to the industry. BASF, for example, exploits the fact that many vitamins and other substances such as carotinoids are insoluble in water, but can easily be mixed with cold water when formulated as nanoparticles. Many lemonades and fruit juices contain these specially formulated additives, which can also be used to provide an ”attractive” color26. Expected breakthroughs in crop DNA decoding and analysis could enable agrifirms to predict, control and improve agricultural production. And with technology for manipulating the molecules and atoms of food, the food industry would have a powerful method to design food with much greater capability and precision, lower costs and improved sustainability. The combination of DNA and nanotechnology research could also generate new nutrition delivery systems, to bring active agents more precisely and efficiently to the desired parts of the human body. Converging technologies could reinvigorate the battered agrochemical and agbiotech industries, possibly igniting a still more intense debate – this time over "atomically-modified" foods. The most cited nano-agricultural developments are:
Nanoseeds: In Thailand, scientists at Chiang Mai University's nuclear physics laboratory have rearranged the DNA of rice by drilling a nano-sized hole through the rice cell's wall and membrane and inserting a nitrogen atom. So far, they've been able to change the colour of the grain, from purple to green.
Nanoparticle pesticides: Monsanto, Syngenta and BASF are developing pesticides enclosed in nanocapsules or made up of nanoparticles. The pesticides can be more easily taken up by plants if they're in nanoparticle form; they can also be programmed to be ”time-released.”
Nanofeed for Chickens: With funding from the US Department of Agriculture (USDA), Clemson University researchers are feeding bioactive polystyrene nanoparticles that bind with bacteria to chickens as an alternative to chemical antibiotics in industrial chicken production.
Nano Ponds: One of the USA’s biggest farmed fish companies, Clear Spring Trout, is adding nanoparticle vaccines to trout ponds, where they are taken up by fish.
”Little Brother”: The USDA is pursuing a project to cover farmers’ fields and herds with small wireless sensors to replace farm labour and expertise with a ubiquitous surveillance system.
Nano foods: Kraft, Nestlé, Unilever and others are employing nanotech to change the structure of food – creating ”interactive” drinks containing nanocapsules that can change colour and flavour (Kraft) and spreads and ice creams with nanoparticle emulsions (Unilever, Nestlé) to improve texture. Others are inventing small
June2015,Issue Page 4 Glacier Journal Of Scientific Research ISSN:2349-8498 nanocapsules that will smuggle nutrients and flavours into the body (what one company calls ”nanoceuticals”).
Nano packaging: BASF, Kraft and others are developing new nanomaterials that extend food shelf life and signal when a food spoils by changing colour.
Food safety: Scientists from the University of Wisconsin have successfully used single bacterial cells to make tiny bio-electronic circuits, which could in the future be used to detect bacteria, toxins and proteins. Nanosensors can work through a variety of methods such as by the use of nanoparticles tailor-made to fluoresce different colors or made from magnetic materials can selectively attach themselves to food pathogens. Handheld sensors employing either infrared light or magnetic materials could then note the presence of even minuscule traces of harmful pathogens. The advantage of such a system is that literally hundreds and potentially thousands of nanoparticles can be placed on a single nanosensor to rapidly, accurately and affordably detect the presence of any number of different bacteria and pathogens. A second advantage of nanosensors is that given their small size they can gain access into the tiny crevices where the pathogens often hide, and nanotechnology may reduce the time it takes to detect the presence of microbial pathogens from two to seven days down to a few hours and, ultimately, minutes or even seconds.
BIOSENSORS TO DETECT NUTRIENTS AND CONTAMINANTS
Protection of the soil health and the environment requires the rapid, sensitive detection of pollutants and pathogens with molecular precision. Soil fertility evaluation is being carried out for the past sixty years with the same set of protocols which may be obsolete for the current production systems and in the context of precision farming approaches. Accurate sensors are needed for in situ detection, as miniaturized portable devices, and as remote sensors, for the real time monitoring of large areas in the field. These instruments are able to reduce the time required for lengthy microbial testing and immunoassays. Application of these instruments include detection of contaminants in different bodies such as water supplies, raw food materials and food products. Enzymes can act as a sensing element as these are very specific in attachment to certain biomolecules. Electronic nose (E-nose) is used to identify different types of odors; it uses a pattern of response across an array of gas sensors. It can identify the odorant, estimate the concentration of the odorant and find characteristic properties of the odor in the same way as might be perceived by the human nose. It mainly consists of gas sensors which are composed of nanoparticles e.g. ZnO nanowires. Their resistance changes with the passage of a certain gas and generates a change in electrical signal that forms the fingerprint pattern for gas detection. Biosensors provide high performance capabilities for use in detecting contaminants in food or environmental media. They offer high specificity and sensitivity, rapid response, user-friendly operation, and compact size at a low cost. While the direct enzyme inhibition sensors currently lack the analytical ability to discriminate between multiple toxic substances in a sample (such as simultaneous presence of heavy metal and pesticide), they may prove useful as a screening tool to determine when a sample
June2015,Issue Page 5 contains one or more contaminants. These methods are amenable to deployment in single-use test strips (making them useful to those in the field). According to, detection of multiple residues of organophosphorus pesticides has been accomplished using a nanomagnetic particle in an enzyme linked immunosorbent assay (ELISA) test. The authors suggest that ELISA is more cost-effective than analytical tests requiring expensive laboratory equipment with high levels of skill.
APPLICATION OF NANOTECHNOLOGY IN ANIMAL SCIENCES
Nanotechnology has the ability to provide appropriate solutions for addressing the issues of food items, veterinary care and prescription medicines as well as vaccines for domesticated animals. Taking certain medications such as antibiotics, vaccines, and probiotics, would be effective in treating the infections, nutrition and metabolic disorders, when used at the nano level. Medicines used at the nano level have multilateral properties to remove biological barriers for increased efficiency of the applied medicine. Appropriate timing for the release of drug and self-regulatory capabilities are the main advantages of the use of nanotechnology in the application of drugs. The C-60 carbon particle (bucky ball) is spherical molecule having nearly 1 nm diameter. It is non-toxic to the live cells and biocompatible in nature. It can be used as a carrier to deliver the water soluble peptides and drugs. The nanotechnology can help to understand certain drug behaviour in an animal body. The nano particles can penetrate the skin through minor abrasions; these are reported to be used as sensor to detect the altered cell behaviour. The dendrimers are synthetic three dimensional macromolecules having a core particle surrounded by branches like a tree. They can be conjugated with the target molecule like drug as they are biocompatible and are easily cleared from blood through the kidney. It was observed that in vivo delivery of dendrimer methotrexate reduce the tumour size ten times more than the free methotrexate. The nano-magnets can be used as drug delivery system specially to treat the cancerous growth without any harm to the surrounding tissues. Different types of proteins like albumin, gelatin, gliadin and legumin can be used to prepare nanoparticle- based drug delivery system. Inert nanobeads were used to neutralize the antigen causing osteoarthritis in racing horses. Use of nano based antibiotics in treatment of animal diseases requires less amounts of antibiotics leaving less antibiotic residues. Nanoparticle based chromium supplementation has beneficial effects on growth performance and body composition and it increases tissue chromium concentration in the muscles. Iron deficiency is a common problem in animals, especially during the early stage of life, gestation and parasitic infestation due to less bioavailability. The bioavailability can be increased with the supplementation of ferric phospholic nano- particles. Nanotechnology is used to produce the chicken/ goat meat in the laboratory in large quantities maintaining the same nutritive value, taste, texture without any hazard (vegetarian meat). It can be eaten by the vegetarians also. It may solve the food scarcity problem, thereby eradicating the hunger. Use of nanotechnology in designer egg production is well-known. It can produce the eggs with low cholesterol, less yolk content, more nutrients, and desired antibodies. In addition, nano-based sensors can help in early detection of egg-borne pathogens.
June2015,Issue Page 6 Glacier Journal Of Scientific Research ISSN:2349-8498
NANOLIGNOCELLULOSIC MATERIALS
Recently, nanosized lignocellulosic materials have been obtained from crops and trees which had opened up a new market for innovative and value-added nanosized materials and products, e.g. nano-sized cellulosic crystals have been used as lightweight reinforcement in polymeric matrix (Mathew et al., 2009). These can be applied in food and other packaging, construction, and transportation vehicle body structures. Cellulosic nano-whisker production technology from wheat straw has been developed by the Michigan Biotechnology Incorporate (MBI) International, and is expected to make biocomposites that could substitute for fiberglass and plastics in many applications, including automative parts. For the commercialization of this technology, North Dakota State University (NDSU), USA is currently engaged in a project.
NANODISPERSIONS AND NANOCAPSULES
The fundamental components of foods such as vitamins, antimicrobials, antioxidants, and preservatives come in various molecular and physical forms. They are rarely used in pure form, they are usually part of a delivery system. A delivery system has numerous functions, only one of which is to transport a functional ingredient to its desired site. Besides being compatible with food product attributes such as taste, texture, and shelf life, other functions of a delivery system include protecting an ingredient fromchemical or biological degradation, such as oxidation, and controlling the functionaling redient’s rate of release under specific environmental conditions. Because they caneffectively perform all these tasks, nanodispersions and nanocapsules are ideal mechanisms for delivery of functional ingredients. These types of nanostructures include: association colloids, nanoemulsions and biopolymeric nanoparticles. A delivery system must perform a number of different roles: – it serves as a vehicle for carrying the functional ingredient to the desired site of action – it may have to protect the functional ingredient from chemical or biological degradation (for example, oxidation) during processing, storage, and utilization; this maintains the functional ingredient in its active state – it may have to be capable of controlling the release of the functional ingredient, such as the release rate or the specific environmental conditions that trigger release (for example, pH, ionic strength, or temperature) – the delivery system has to be compatible with the other components in the system, as well as being compatible with the physicochemical and qualitative attributes (that is, appearance, texture, taste, and shelf-life) of the final product. The characteristics of the delivery system are one of the most important factors influencing the efficacy of functional ingredients in many industrial products. A wide variety of delivery systems has been developed to encapsulate functional ingredients, including simple solutions, association colloids, emulsions, biopolymer matrices, and so on. Each type of delivery system has its own specific advantages and disadvantages for encapsulation, protection, and delivery of functional ingredients, as well as cost, regulatory status, ease of use, biodegradability, and biocompatibility.
June2015,Issue Page 7 Association Colloids
A colloid is a stable system of a substance containing small particles dispersed throughout. An association colloid is a colloid whose particles are made up of even smaller molecules. Used for many years to deliver polar, nonpolar, and amphiphilic functional ingredients. Association colloids range in size from 5 nm to 100 nm and are usually transparent solutions. Surfactant micelles, vesicles, bilayers, reverse micelles, and liquid crystals are all examples of association colloids. The major disadvantages to association colloids are that they may compromise the flavor of the ingredients and can spontaneously dissociate if diluted. The major advantages of association colloid systems are that they form spontaneously, are thermodynamically favorable, and are typically transparent solutions. The formation of association colloids is concentrationdriven. Diluting the solutions containing the colloids can lead to their spontaneous dissociation. It is worth to mention that a large quantity of surfactant (and in many cases, co-surfactant) is required to form them, which may lead to problems with flavor, cost, or legality.
NANO EMULSION
The use of high-pressure valve homogenizers or microfluidizers often causes emulsions with droplet diameters of less than 100 to 500 nm. In modern literature such emulsions are often referred to as “nano-emulsions”. They have been produced and studied for many years, so a large body of literature dealing with their preparation, characterization, and utilization exists [McClements 2004]. Functional food components can be incorporated within the droplets, the interfacial region, or the continuous phase. Encapsulating functional components within the droplets often enables a slowdown of chemical degradation processes by engineering the properties of the interfacial layer surrounding them.
NANOSTRUCTURED MULTIPLE EMULSIONS
The use of multiple emulsions can create delivery systems with novel encapsulation and delivery properties. The most common examples of this are oil-in-water-in-oil (O/W/O) and water-in-oil in-water (W/O/W) emulsions. Functional food components could be encapsulated within the inner water phase, the oil phase, or the outer water phase, thereby making it possible to develop a single delivery system that contains multiple functional components [Flanagan and Singh 2006].
BIOPOLYMERIC NANOPARTICLES
Food-grade biopolymers such as proteins or polysaccharides can be used to produce nanometer sized particles . Using aggregative (net attraction) or segregative (net repulsion) interactions, a single biopolymer separates into smaller nanoparticles. The nanoparticles can then be used to encapsulate functional ingredients and release them
June2015,Issue Page 8 Glacier Journal Of Scientific Research ISSN:2349-8498 in response to distinct environmental triggers. One of the most common components of many biodegradable biopolymeric nanoparticles is polylactic acid (PLA). Widely available from a number of manufacturers, PLA is often used to encapsulate and deliver drugs, vaccines, and proteins, but it has limitations: it is quickly removed from the bloodstream, remaining isolated in the liver and kidneys. Because its purpose as a nanoparticle is to deliver active components to other areas of the body, PLA needs an associative compound such as polyethylene glycol to be successful in this regard . NANOLAMINATES
Nanotechnology provides food scientists with a number of ways to create novel laminate films suitable for use in the food industry. A nanolaminate consists of 2 or more layers of material with nanometer dimensions that are physically or chemically bonded to each other. Nanolaminates can give food scientists some advantages for the preparation of edible coatings and films over conventional technologies and may thus have a number of important applications within the food industry. Edible coatings and films are currently used on a wide variety of foods, including fruits, vegetables, meats, chocolate, candies, bakery products, and French fries. These coatings or films could serve as moisture, lipid, and gas barriers. Alternatively, they could improve the textural properties of foods or serve as carriers of functional agents such as colors, flavors, antioxidants, nutrients, and antimicrobials. The basic functional properties of edible coatings and films depend on the characteristics of the film forming materials used for their preparation. The composition, thickness, structure, and properties of the multilayered laminate formed around the object could be controlled in a number of ways, including changing of the type of adsorbing substances in the dipping solutions, the total number of dipping steps used, the order that the object is introduced into the various dipping solutions, the solution and environmental conditions used (pH, ionic strength, dielectric constant, temperature, etc.). The driving force for adsorption of a substance to a surface would depend also on the nature of the surface and the nature of the adsorbing substance and it could be: electrostatic, hydrogenbonding, hydrophobic interactive, thermodynamically incompatible, etc.
NANOFIBERS AND NANOTUBES
Two applications of nanotechnology that are in the early stages of having an impact on the food industry are nanofibers and nanotubes. Because nanofibers are usually not composed of food-grade substances, nanofibers have only a few potential applications in the food industry. Produced by a manufacturing technique using electrostatic force, nanofibers have small diameters ranging in size from 10 nm to 1000 nm. As advances continue in the area of producing nanofibers from food-grade materials, their use will likely increase. As with nanofibers, the use of nanotubes has predominantly been for non-food applications. Carbon nanotubes are popularly used as low resistance conductors and catalytic reaction vessels. Under appropriate environmental conditions, however, certain globular milk proteins can self-assemble into similarly structured nanotubes [Graveland-Bikker et al. 2006].
NANOTECHNOLOGY IN FOOD PROCESSING
June2015,Issue Page 9 Up to now in this chapter, the nanotechnology applications have been referred to water use and commodity production but, nanotechnology can be a way to get better manufacturing food process (or even a completely new and different one). Actually, food sector could be facing a paradigm shift., nowadays foods are structured using a recipe (o formulation) whereas two simultaneous processes occur:- Formation the structure (i.e: by means of phase creation, reactions, biopolymer transformation) - Stabilization of the system (i.e. vitrification, crystallization, network formation) On the other side, nanotechnology affords the possibility of structure foods from the base elements (in an approach derived from its constituents self-assembly). Rather than the use of a recipe, nanotechnology raises the opportunity of using molecules as starting material, so that new interaction are achieved which in turn generates the required properties. The paradigm shift resides in the fact the food formulation will based on the use of “food matrix precursors or structural elements”. To achieve this possibility it will be necessary the development of new knowledge and techniques. Some examples on the potentiality of the former approach is the development of new textures and flavours, the possibility of the design of low dense, low calorie foods but nutritionally enhanced. Those foods can be aimed at a nutrition adapted to different lifestyle and consumer conditions (i.e. obesity cases). Two points are commented here to give a general view of the multiple possibilities of nanotechnology use in food processing: - Food processing issues: mixing, component stability, safety, etc. - Intrinsic food features: texture, flavour, taste masking, availability and delivery, etc. Among the processing issues the most of the applications are related with the use of nanoparticles and nanocapsules. These particles enhance the products functionality, and they are responsible of that enhancement because they perform a protection function on: - The contained active principle. Nanoparticles avoid the degradation produced by the surrounding environment of the food or by the manufacturing process. Gökmen et al., 2011, have reported that omega 3 was successfully nanoencapsulated and used in bread making. In addition of the positive effect in taste masking, thermooxidation during baking was reduced. As a consequence of that, the production of other further degradation by-products (i.e. acrylamide) was strongly reduced. - The food itself. This happens when the active principle is used with a technological purpose. For instance nanoparticles containing essential oil have been used to improve antimicrobial activity in juices. In this case, the addition of small amounts of nanoparticles containing terpenes to an orange and pear juice delayed or avoided the microbial growth (depending on the concentration). Organoleptic properties were maintained. One advanced aspect of the use of nanotechnology is the possibility of acting straight onto the food structure. Nanostructured foods aimed at producing better texturized, flavoured and other properties can be obtained. In particular it can be highlighted the possibility of producing cream-like foods such as: ice-creams, spreads
June2015,Issue Page 10 Glacier Journal Of Scientific Research ISSN:2349-8498 and low fat dressings. Leser et al., 2006, comment how polar lipids (monoglycerides and phospholipids) can be used with this purpose. Some of those polar lipids are capable of create nanostructures that finally result in crystalline phases. These structures can be used as a base for the development of spreads taking advantage on the texture properties emerging from interaction between nanostructures clusters. The manufacturing process will depend on water relative quantity, stirring, and the system temperature evolution. The contribution of particles to the stability of foams and emulsions is another aspect of interest in the use of nanotechnology in foods. Most of the foods are (or have been during processing) dispersions like emulsions or foams. Several examples could be derived from bakery, confectionery, meat products, dressings and spreads. Another example is the prepared foods. In general, foam and emulsion stability can be improved in the presence of nanoparticles and nanostructures. The macroscopic properties of dispersion can be improved by controlling the formation of nanostructures in the interphase. The application of new techniques to food development such as Brewster angle microscopy (BAM), atomic force microscopy (AFM) y imaging ellipsometry (IE), will allow the study and application of those possibilities to processing. Dickinson, 2010 presents a review about the use of inorganic nanoparticles (silica), fat crystals and protein nanoparticles. Main conclusions to highlight are: - “Natural biopolymer structural assemblies are obviously attractive as (nano)particle building blocks” - Polysaccharides (i.e. starch or cellulose) represent can be considered as a cheap and a quickly source of nanomaterial for food uses. Anyhow, it is required some type of modification to increase hydrophobicity. - Proteins represent the best potential derived from the amphiphilic behaviour as well as due to their carrying capacity (i.e. casein nanotubes) - The interaction between protein and polysaccharides is of great interest also. For instance, the interaction obtained from the interaction of caseinate and Arabic gum or, the heat degraded beta-lactoglobulin aggregates and stabilised by pectin. One important implication of this type of interaction could be the complexing between casein and a charged polysaccharide which can be used in the maintenance of solubility and functionality under acidic pH conditions Another relevant aspect in food processing is the time. In this case, when considering the interaction between food components in a structure, the time required to reach a position should be considered. “In order to interact, different components of a food structure must come into position at the right time.” For example, the foam formation is a kinetic process that is initiated at the nanoscale in miliseconds, after that foam is stabilised at macroscopic level in the order of minutes. The capability of nanoparticles and nanosystems to arrange in time is then another issue to consider. In this sense, Sánchez & Patino, 2005 have reported how the diffusion speed of caseinate to the liquid-air interphase affects to the foam formation and, how depending on the concentration (above 2%), interphase saturation occurs and appear a micelle formation for sort times. Besides processing features, a possible breakthrough in food manufacturing is the enhancement of the bioavailability.
June2015,Issue Page 11 Nanoemulsions and nanoparticles suppose a delivery vehicle capable of override two great problems: - Conservation in the food previous to the consumption and the stomach degradation - The absorption of the compounds by the organism In the last case, it should be considered that the main absorption route of foods is the intestine and nanotechnology could improve that somehow. Direct absorption of nanoparticles is controlled by size and surface chemistry of the particle. Generally nanoparticles can be done by an active transport mechanism or by a passive transport. In the first case (active transport) absorption happens by means of specific channels that present the epithelial intestinal cells. In this case absorption is controlled by the hormonal system and by homeostatic effect derived from blood levels of compounds. According to the last control mechanism, once a level is surpassed for an ingredient, it will be not absorbed and the excess is accumulated or excreted. Selective absorption can be conditioned by specific receptors in the cell surface (enterocytes and M cells). Those nanoparticles with a specific surface composition can be absorbed by this way. Generally, the M cells present a better permeability. For example, there is a great interest in the development of lecithin nanoparticles since it could be an improvement in the absorption of isoflavones by this route. Passive transport happens by means of diffusion though epithelial tissue. The particle has to be fixed to intestinal mucosa, and from there, to contact the cell. The absorption speed is determined by a concentration gradient. In an interesting work studied the use in vivo of lipidic core nanocapsules. Those nanocapsules are fixed to gastrointestinal lumen and act as active principle reservoirs. Nanocapsules delivered the active principle once they were fixed by diffusion. As relevant conclusion of this work it is pointed that there is important differences between evaluation models used (in vivo and ex vivo), and the live model system complexity cannot be predicted by a simpler model, at least at this time. In fact, nanomaterial dosimetry it is not clear at all. Despite this, there is a general consensus about the relation of particle size and bioavailability in the sense that, as far the size decreases, the bioavailability is improved. A size reduction under 500 nm produces a higher absorption of the active principle and more particle uptake regardless of the system composition. However, above 500 nm, the bioavailability depends on the system. So, it is possible to obtain more effect from a food additive with the use of nanotechnology (with lower content in an active principle) than with the use of the traditional approach (i.e. microencapsulation).
FOOD PACKAGING
Today, food packaging and monitoring are a major focus of food industry-related nanotech R&D. Packaging that incorporates nanomaterials can be “smart,” which means that it can respond to environmental conditions or repair itself or alert a consumer to contamination and/or the presence of pathogens. According to industry
June2015,Issue Page 12 Glacier Journal Of Scientific Research ISSN:2349-8498 analysts, the current US market for “active, controlled and smart” packaging for foods and beverages is an estimated $38 billion - and will surpass $54 billion by 2008. The following examples illustrate nanoscale applications for food & beverage packaging. Using Clay Nanoparticles to Improve Plastic Packaging for Food Products Chemical giant Bayer produces a transparent plastic film (called Durethan) containing nanoparticles of clay. The nanoparticles are dispersed throughout the plastic and are able to block oxygen, carbon dioxide and moisture from reaching fresh meats or other foods. The nanoclay also makes the plastic lighter, stronger and more heat-resistant. Barrier Packaging For some time now, food has been packaged in a protective, oxygen-free atmosphere. Standard packing film made from flexible plastics, however, is slightly permeable to oxygen and other gases. Over time, this means that the protective atmosphere can leak out, and oxygen can leak in, damaging the food. A coating of metal or glass, which are totally impermeable to gases, would prevent this from happening - this is obviously impractical however, as it would reduce flexibility, and would be much more expensive than plastic packaging. This is where nanotechnology comes to the rescue - a coating just a few nanometres thick is sufficient to create an impermeable layer, without compromising on flexibility or adding a great deal to the cost. Antimicrobial Packaging As well as behaving as a simple passive barrier, packaging can be enhanced to actively reduce the growth of harmful microbes. Antibacterial coatings most often use silver nanoparticles, which are becoming more and more common in everything from wound dressings to electrical appliances. Other antimicrobial materials have been investigated, and will most likely see increased use in packaging in the coming years. These include zinc oxide nanoparticles, which become more antibacterial as their particle size gets smaller, and chitin, which is a natural substance found in the shells of crustaceans like crabs and shrimps. Active or "Smart" Packaging Researchers have started to explore the possibilities of "smart" packaging. Rather than just keeping food from going off for as long as possible, packaging with embedded smart materials and flexible nanoelectronics could actively control the environment inside the packaging, and alert consumers when the food has begun to decay. Self-cooling packaging has been suggested, which would use a chemical or physical process, such as evaporation of a gas, to keep the temperature inside the packaging cool. Powered systems could also use a thin-film photovoltaic cell to power cooling using a thermoelectric material.
June2015,Issue Page 13 This would reduce the need for large-scale refrigeration along the supply chain, although it is unclear whether or not there would be a cost benefit in this case. Self-healing polymers have been under investigation by researchers for quite some years now, and some examples have appeared on the market. Use of these materials as an outer layer in food packaging could allow small punctures and tears in the wrapping, reducing wastage due to damaged packaging. One interesting development is the use of nanoparticles to create colour-changing plastic packaging which indicated when food is going off. There are two main mechanisms to achieve this - chemical and physical. The chemical mechanism uses a chemical indicator which changes colour in the presence of gases given off when food oxidizes. The physical mechanism uses nanoparticles embedded in the polymer layers which change their optical properties depending on their relative position in the lattice structure. This can be designed so that an intense colour is produced when the packaging stretches, creating an obvious indication of gas-releasing decomposition.
CONCLUSION
Promising applications of nanotechnology may be in meat packaging, through systems which possess efficient barrier and antimicrobial properties as well as in meat processing through improvement of sensory characteristics, and nanoencapsulation of bioactive compounds. Other prospects include improvements in the nutrition and functional properties of meat products. However, the application of nanotechnology in meat remains a huge challenge. The application of nanoemulsions in meat products has faced problems such as oxidative instability and short-lived antimicrobial effects. The use of nanopowders is also hindered by the lack of efficient equipments for processing, along with the nature of the ingredients themselves. Other nanomaterials, depending on the type, have preparation methodologies which can be difficult, and lack scalability, performance efficiency and cost effectiveness. Potential health risks associated with the use of some nanomaterials is another major concern, but is dependent on the characteristics of the nanomaterials as well as the biokinetics of the human body in response to the materials. However, with increasing research activities, and development of associated technologies, instruments and methodologies, nanotechnology can significantly contribute to meat industries. Apart from filling the knowledge gaps in the production and safety of nanomaterials, improving public acceptance, economics and pragmatic regulation could be important for the successful future application of nanotechnology in meat products and packaging.
REFERENCES
Chen L., Subirade M. 2005. Chitosan/β-lactoglobulin core–shell nanoparticles as nutraceutical carriers. Biomaterials.
June2015,Issue Page 14 Glacier Journal Of Scientific Research ISSN:2349-8498
Cockburn A., Bradford R., Buck N., Constable A., Edwards G., Haber B., Hepburn P., Howlett J., Kampers F., Klein C., Radomski M., Stamm H., Wijnhoven S., Wildeman T. 2012. Approaches to the safety assessment of engineered nanomaterials (ENM) in food. Food Chem Toxicol. Flanagan J., Singh H. 2006. Microemulsions: A potential delivery system for bioactives in food. Crit Rev Food Sci Nutr. 46:221–237. Gupta AK and Gupta M. 2005. Synthesis and surface engineering of iron oxide nanoparticles for biomedical applications. Biomaterials. Graveland-Bikker JF., de Kruif CG. 2006. Unique milk protein based nanotubes: food and nanotechnology meet. Trends Food Sci Technol. 17:196–203. McClements DJ., Rao J. 2011. Food-grade nanoemulsions: formulation, fabrication, properties, performance, biological fate, and potential toxicity. Crit Rev Food Sci Nutr. 51:285–330. Olmedilla-Alonsoa B., Jiménez-Colmeneroa F., Sánchez-Muniz FJ. 2013. Development and assessment of healthy properties of meat and meat products designed as functional foods. Meat Sci. Rhim JW., Park HM., Ha CS. 2013. Bio-nanocomposites for food packaging applications. Prog Polym Sci. Sozer N., Kokini JL. 2009. Nanotechnology and its applications in the food sector. Trends Biotechnol. Troy DJ., Kerry JP. 2010. Consumer perception and the role of science in the meat industry. Meat Sci. USDA. 2008. Food safety information: additives in meat and poultry products. United States Department of Agriculture;http://www.fsis.usda.gov/wps/portal/fsis/topics/food- safety-education/get-answers/food-safety-fact-sheets/food-labeling/additives-in-meat- and-poultry-products/additives-in-meat-and-poultry-products. Accessed November 3, 2014 Weiss J., Gibis M., Schuh V., Salminen H. 2010. Advances in ingredient and processing systems for meat and meat products. Meat Sci Weiss J., Takhistov P., Mcclements J. 2006. Functional materials in food nanotechnology. J Food Sci. . Table 1:Nanomaterials for delivery of functional ingredients in meat products Function of Nanomaterial nanomaterial Meat product Performance in meat Micelle (NanoparticleEncapsulation ofChicken breastImproved marinating paprika oleoresin) functional fillet performance and sensory ingredient perception
June2015,Issue Page 15 Function of Nanomaterial nanomaterial Meat product Performance in meat Biopolymeric Antimicrobial Fish Finger Increased antimicrobial nanoparticle (Chitosan activity nanoparticle) O/W NanoemulsionAntimicrobial Indo-Pacific Short lived antimicrobial (Sunflower oil) king mackerel Steaks PLGA nanoparticlesAntimicrobial Raw & cooked Efficient (phenolics loaded) meat systems antimicrobialactivity
Table 2:Nanomaterials for meat packaging Meat Nanomaterial Carrier film product Effect Montmorillonite Polyamide 6 (PA6) Beef loins (Improved packaging ) (MMT) nanoclays Enhanced shelf life of meat lowered thickness of packaging material Zinc oxide (ZnO)Low densityChicken (Active packaging) Inhibition +silver (Ag)polyethylene (LDPE) breasts of Escherichia coli, nanoparticles Pseudomonas aeruginosa, Listeria monocytogenes Carbon nanotubeAllyl IsothiocyanateCooked Reduction in Salmonella (CNT) (AIT) in cellulosechicken choleraesuis polymer breast Reduction in oxidation and color changes Semiconductor Polyethylene Uncooked (Smart packaging) Oxygen nanocrystals bacon nanosensors for O2 detection
Assurance of package seal integrity
June2015,Issue Page 16