Nanotechnology

Back to EFFICIENCY FINDER OF FOOD INDUSTRY

General Information

Overview

The origin of nanotechnology descends of many scientific and engineering fields. It is essentially the manipulation and control at a very small scale (based on physical and chemical principles). Crucial events in the initial development of the technology were the scanning tunnelling microscope, the atomic force microscope and the Eigler-Schwarzer experiment. Early and intense applications are found on nanolithography and computer components fields. In the field of electronics, textiles, drug delivery and new materials the focus on nanotechnology has been intense in the last years (Tourney 2010; Anthierens, et al. 2012 ). The food processing industry can capitalize in the findings and techniques developed to solve the current problems or even shape the whole industry.

Advantages

• Use of natural compounds (i.e. plant oils) in combination with tailored structure that enhances desired effects (Donsi et al. 2014).
• It enables possibilities for new materials.
• Nano scale design using energy and materials more effectively.
• Ultrafine products and processes (Nieuwland et al. 2014; Pinheiro et al. 2012).

Disadvantages

• High level of expertise needed.
• Governance and nanotech policies are challenging due to the complexity of the technology evaluation (Tourney 2010).

Base

• Nano design of delivery mechanism based on emulsion systems or nano-containers structures that enables a controlled delivering of sustances (Anthierens, et al. 2012; Pinheiro et al. 2012). These structure designs can also target a modification in the structure on food, as shown in the Change in Process Section (Nieuwland et al. 2014).
• The antibacterial nature of frequently used compounds is mainly due to the effect of hydrophobic nature and the free hydroxyl function in the compounds interacting with the membrane of the bacteria. In the first case, the lipid bilayer of the cytoplasmic membrane is expanded and destabilized increasing its fluidity and permeability. In the second case, it acts as a proton exchanger, the gradient across the membrane is reduced leading to the cell death to a decrease of Adenosine triphosphate (Anthierens, et al. 2012).

Description of techniques

The techniques mainly refer to the implementation of structure at the nano metric scale in or on the food product. Based on the found applications, there are two main targets for the structures 1) To target a change directly in the structure of the food (like in cooking) 2) To target the creation of a delivery system (in packaging or in the food itself). Due to the tailored characteristics of nanotechnology applications, a further common description of technology is not convenient.

Changes in process (Operation Unit Applications

Cooking

Nanotechnology can enable a designed texture of food, being especially relevant for meat substitutes. Solution of growing population a growing demand of proteins. Alternatives sources of proteins as leaf proteins or insect proteins (Nieuwland et al. 2014).

Non-meat product with appealing structure are difficult to produce, although it is possible to produce thin fibrils as building blocks for texturally meat replacers. Electros pining produces thin fibrils with a high aspect ratio. Under a high voltage, a polymers solution produce fibrils. The targeted polymer needs to be highly soluble and able to entangle at the same time that the immersing solution must have the right conductivity, viscosity (depended on concentration, high enough to reach entangling but still at a workable level of viscosity) and surface tension. Polymers have been used in biomedical application but they are not suitable for food application. Only two proteins are known to spin under food-grade and it is a possibility to use one of these proteins as a carrier for other proteins. Zein and gelatin proteins have been explore to be used as carriers. Being soluble and in a random coil structure is the most challenging processing stages in the electro spinning of proteins (Nieuwland et al. 2014). Process parameters optimization are the used voltage, the flow speed, the distance to collector among others (Nieuwland et al. 2014).

• Fixation and alignment of the fibrillar structures are also needed and up calling processes need to be explored (Nieuwland et al. 2014).

Pasteurization/Blanching

Nanotechnology enable a slow and sustained release of the antimicrobial compounds and can also contribute to their incorporation in complex food systems. There is a high potential for replacing artificial compounds to meet the growing needs of consumers for more healthy products keeping the preservation standards. The antimicrobial effect is generated due to a synergy with another compound that can be natural avoiding the use of artificial preservatives (Donsi et al. 2014).

Essential oils extracted from plants and fruits incorporate different components with significant biological activity, such as anti-inflammatory, expectorant, carminative, psychoactive, pesticide and antimicrobial properties (Donsi et al. 2014). The mechanism of antibacterial action of these oils is mainly based on the hydrophobicity of their constituent molecules. Suitable carriers that promote dispersion and enhance mass transfer can be used. Encapsulation of EOs in appropriate delivery systems can contribute (a) to improve the protection of the bioactive compounds from chemical degradation (b) the dispersion in the aqueous part of the food, where microorganisms proliferate (c) to reduce the impact of EOs on sensorial properties (d) to enhance their biological activity through the promotion of mass transport (Donsi et al. 2014). This development results in “Nano-tanks” for the oils, improving their dispersion in aqueous phase and ensuring a sustained concentration of the active compounds over an extended period of time.

Washing

Nanotechnology can enables a minimal processing for fresh fruits and other products from the post harvest industry. The technology can enable a system that combine functionally and edibility (Pinheiro et al. 2012).

• Chitosan and K carrageenan nano layered coating and promising plataform from which the controlled release of different bioactive compound can be explored. Chitosan is a cationic polysaccharide obtained from chitin. It is an excellent edible component due to its oxygen barriers properties and its intrinsic antibacterial properties. K carrageenan is a sulphated anionic polysaccharide extracted from certain seaweeds is used as gelling and stabilizing agent. It has been reported excellent film forming properties. Great potential for coat food systems such as fruits, vegetables or cheese and to act as a support for the incorporation of bioactive compounds (Pinheiro et al. 2012).

The release behavior depends on the permeability and on the disassembly or erosion of the multilayer structure and on the other experiment variables (Pinheiro et al. 2012). Transport of molecules as the sum of the molecules transport by Brownian motion with the molecules transported due to polymer relaxation. With increase processing temperature, promote molecular vibration and movement increasing the delivery rate. The relaxation rate constant decreased with increased with increasing pH, effect of acidic pH on promoting transport through relaxation on the polymeric network. Parameters: Layer position, pH and Temperature (Pinheiro et al. 2012).

Mass loaded increase with the distance from the first layer. The quantity of the mass loaded and the release and the rate of release can be controlled by altering the position of the compound of interest within the nanolayed structure (Pinheiro et al. 2012).

Packaging

Nanotechnology enables a diversification in the packaging sector which relies strongly in the use of petroleum derived, whereas it is raising environmental and economics concerns. This diversification can be done through the use of biodegradable, bio-based food-packaging materials able to preserve and ensure the shelf life of food (Anthierens, et al. 2012).

Active packaging are materials that extend the shelf life, to maintain or improve the conditions of food. Active packaging relies on release system often based on antioxidants or antimicrobials sustained delivery providing the effect on the food surface where most of the spoilage occurs, avoiding the standard extra amount of preservative that need to be added to food (Anthierens, et al. 2012). There are several approaches as the incorporation of the active compound into the packaging material, the encapsulation of the active compound into the polymer matrix or the development of multilayer structures with one or more external layers containing active compounds (Anthierens, et al. 2012).

The use of use of compounds find in plants and oils can be used and the delivery system can be designed in a way that take advantages of the antibacterial properties avoiding often undesirable effects (as organoleptic alterations). It can also help to improve the limits of the application of some compounds due to their hydrophobic nature and volatility by the gradual release of small amount over a longer period of time (Anthierens, et al. 2012).

A case of elaboration of a bio-nano-material for food-packaging uses a paper substrate coated using two delivery systems: cyclodextrin and mircofibrillated cellulose. Cyclodextrins are cyclic oligosaccharides composed of D-glucose units linked by alfa glucosidic linkages; the inclusion of host complexes is mainly driven by hydrophobic or Van der Waals interactions. This system has been used in the textile and biomedical industries. Micorfibrillated Cellulose is produced by high shear mechanical treatment of cellulose fiber and has been applied as carrier and drug delivery systems (Anthierens, et al. 2012).

References

• Anthierens T., Billiet L., Devlieghere F., Du Prez F. (2012) 'Poly(butylene adipate) functionalized with quaternary phosphonium groups as potential antimicrobial packaging material', Innovative Food Science & Emerging Technologies, 15(), pp. 81–85.
• Donsì, F.; Cuomo, A.; Marchese, E.; Ferrari, G (2014) 'Infusion of essential oils for food stabilization: Unraveling the role of nanoemulsion-based delivery systems on mass transfer and antimicrobial activity', Innovative Food Science & Emerging Technologies,22(), pp. 212–220.
• Toumey, C. (2010) 'Tracing and disputing the story of nanotechnology', in Hodge, G., Bowman, D., Maynard, A. (ed.) International Handbook on Regulating Nanotechnologies.UK: Edward Elgar, pp. 46-59.
• Pinheiro, A., Bourbon, A. I., Quintas, M.A.C., Coimbra, M.A., Vicente, A.A. (2012) 'Κ-carrageenan/chitosan nanolayered coating for controlled release of a model bioactive compound', Innovative Food Science & Emerging Technologies, 16(), pp. 227-232.
• Nieuwland, M.; Geerdink, P.; Brier, P.; Eijnden, P. van den; Henket, J.T.M.M.; Langelaan, M.L.P.; Stroeks, N.; Deventer, H.C. van; Martin, A.H. (2014) 'Reprint of "Food-grade electrospinning of proteins', Innovative Food Science & Emerging Technologies, 24(), pp. 138-44.

Back to EFFICIENCY FINDER OF FOOD INDUSTRY