NanoPackSafer – um novo sistema de embalagem de alimentos

1. Universidade do Minho Instituto para a Biotecnologia e a Bioengenharia NanoPackSafer – um novo sistema de embalagem de alimentos António A. Vicente Departamento de Engenharia Biológica avicente@deb.uminho.pt

2. NanoPackSafer OBJECTIVE: This proposal aims at developing nanotechnology-based food protection strategies by providing active packaging systemswhich will proactively act to maintain or even toincrease food quality, safety and health impactof foods from production to consumption.

3. Nanotechnology According to the European Commission’s Recommendation (EFSA):

4. Nanotechnology According to the US Food and Drug Administration (FDA): Functionality

5. Motivation Environment All bio-materials from renewable sources All food-grade, edible materials Nano-sized systems Ethical aspects Consumers

6. Nano-engineered films and coatings Nano-engineered films and coatings Nano-engineered films and coatings Nano-engineered films and coatings - Clay nanoparticles Nano-engineered films and coatings - Clay nanoparticles Nano-engineered films and coatings - Clay nanoparticles From Macro to Micro to Nano - Can you see me? Can you see me?

7. Nano-engineered films and coatings Nano-engineered films and coatings Nano-engineered films and coatings Nano-engineered films and coatings - Clay nanoparticles Nano-engineered films and coatings - Clay nanoparticles Nano-engineered films and coatings - Clay nanoparticles Nanotechnology – the promise of a food revolution • Improved sensorial properties • Healthier and more nutritious foods • Better packaging systems • Traceability and monitoring along food chain Materials at the nano scale have different properties

8. Nano-engineered films and coatings - nanolaminates

9. Nano-engineered films and coatings - nanolaminates A nanolaminate is a film or coating composed of two or more layers of material with nanometer dimension that are physically or chemically bonded to each other Need for successive layers of materials: • Better physical stability in aggressive environments • Better chemical stability of the incorporated compounds • Improved control of the release rates • Coexistence of possibly incompatible functionalities Advantages of being nano-sized: • Lesser amounts of ingredients needed • Less impact in the sensory attributes of foods • Different behaviour expected in terms of transport properties • Of gases • Of entrapped (functional) solutes

10. Nano-engineered films and coatings - nanolaminates

11. Nano-engineered films and coatings - nanolaminates Alginate layers Chitosan layers

12. Nano-engineered films and coatings - nanolaminates • Characterization of the nanolayered film Gas barrier properties • 1Hoagland and Parris (1996). Journal of Agricultural and Food Chemistry, 44, 1915-1919 • 2 Fajardo et al. (2010). Journal of Food Engineering.

13. Release from chitosan nanolayered films in liquid medium K-carrageenan/chitosan nanolayered film with a model compound (Methylene Blue) incorporated on the 2nd, 4th or 6th layer UV-VIS spectroscopy, 190-800 nm aminolyzed PET + - - + + - - + + - - water water Real time deposition Quartz Crystal Microbalance Negatively Charged: 0.2 % k-carrageenan pH 7 Positively Charged: 0.2 % chitosan, pH 3 or 0.3 % of Methylene Blue, pH 7

14. Release from chitosan nanolayered films in liquid medium MB releasefrom nano layeredfilms Nanolayeredfilmswith MB inthe: 2ndLayer • Incubation of films in 0.01 M PBS • pH 2 and 7 • MB release evaluated by UV-VIS spectroscopy at 600 nm 4thLayer 6thLayer

15. Release from chitosan nanolayered films in liquid medium MB releasefrom nano layeredfilms Nanolayeredfilmswith MB inthe 6thLayer existence of interpenetration between MB in the outermost and k-carrageenan on the 5th layer? Fick´s transport Anomalous behaviour – Fick + 1 main reconfiguration ok

16. Release from chitosan nanolayered films in liquid medium MB releasefrom nano layeredfilms Nanolayeredfilmswith MB inthe 2ndand 4thLayers pH=2 pH=7 Fick´s transport Anomalous behaviour – Fick + 1 main reconfiguration Fick´s transport Anomalous behaviour – Fick + 1 main reconfiguration ok Strong electrochemical interaction - affects the transport mechanism, which cannot be described by neither Fickian nor anomalous behaviour • “Normal” interaction • behaves as a “macro” polymeric • network + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + - - - - - - - - - - - + + + + + + + + + + + + + + + + + + + + - - - - - - - - - - - + + + + + + + + + +

17. Applications • Application on mangoes Contact angle

18. Applications • Application on mangoes – Shelf-life analysis Weight loss The pectin/chitosan nanolayers reduced the weight loss of the mangoes.

19. Applications • Application on mangoes – Shelf-life analysis Soluble solids (SS) Titratable acidity (TA) Mangoes with nanolayers: Lower SS variation and lower redution of TA Delay in ripening

20. Applications • Application on mangoes – Appearance after 45 days Withoutcoating Withpectin/chitosan nanolayers

21. Applications Application on pears – Appearance after 7 days of refrigerated storage

22. Take-home messages Need to improve detection/characterization methods Countless applications in foods Need to evaluate impact on health Need to evaluate impact on environment Ethical aspects? Plenty of room for improvement of food nano-systems

23. Thank you for your attention