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

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

3. Nanotechnology Nanomaterial means a material that meets at least one of the following criteria: consists of particles, with one or more external dimensions in the size range 1 nm - 100 nm for more than 50 % of their number size distribution; has internal or surface structures in one or more dimensions in the size range 1 nm – 100 nm; has a specific surface area by volume greater than 60 m 2 /cm 3, excluding materials consisting of particles with a size lower than 1 nm. According to the European Commission’s Recommendation (EFSA):

4. Nanotechnology Nanomaterial: If an engineered material or final product has at least one dimension at the nanometer scale (1 - 100 nanometers) If an engineered material or final product shows properties or phenomena (including physical, chemical or biological effects) attributable to its dimensions, including if these lay out of the nanometer scale, up to the micrometer According to the US Food and Drug Administration (FDA): Functionality

5. Motivation Consumers EnvironmentAll bio-materials from renewable sourcesAll food-grade, edible materialsNano-sized systemsEthical aspects

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

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

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 10

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

12.  Characterization of the nanolayered film FilmsThickness (µm) WVP x 10 11 (g.m -1.s -1.Pa -1 ) Improved barrier O 2 P x 10 14 (g.m.Pa -1.s -1.m -2 ) Improved barrier Aminolyzed PET 103.001.42 ± 0.39---------2.50 ± 0.03-------- PET + 5 layers 103.271.08 ± 0.10---------2.12 ± 0.03-------- 5 layers0.270.019 ± 0.005 ---------0.069 ± 0.006-------- Pectin 1 100-15061.9 ± 5.614.2 %--------------------- Chitosan 2 45-508.60 ± 0.1438.9 %7.12 ± 0.23170 % Gas barrier properties 1 Hoagland and Parris (1996). Journal of Agricultural and Food Chemistry, 44, 1915-1919 2 Fajardo et al. (2010). Journal of Food Engineering. Nano-engineered films and coatings - nanolaminates

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

14. Nanolayered films with MB in the: 2 nd Layer 4 th Layer 6 th Layer MB release from nano layered films  Incubation of films in 0.01 M PBS  pH 2 and 7  MB release evaluated by UV-VIS spectroscopy at 600 nm Release from chitosan nanolayered films in liquid medium

15. Nanolayered films with MB in the 6 th Layer MB release from nano layered films Fick´s transport Anomalous behaviour – Fick + 1 main reconfiguration ok Release from chitosan nanolayered films in liquid medium

16. Nanolayered films with MB in the 2 nd and 4 th Layers MB release from nano layered films Fick´s transport Anomalous behaviour – Fick + 1 main reconfiguration pH=7 ++++++++++ --- - - - ----- ++++++++++ --- - - - ----- Strong electrochemical interaction - affects the transport mechanism, which cannot be described by neither Fickian nor anomalous behaviour ++++++++++ ++++++++++ ++++++++++ ++++++++++ Fick´s transport Anomalous behaviour – Fick + 1 main reconfiguration pH=2 ok “Normal” interaction -behaves as a “macro” polymeric network Release from chitosan nanolayered films in liquid medium

17.  Application on mangoes Contact angle Applications

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

19.  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 Applications

20.  Application on mangoes – Appearance after 45 days Without coating With pectin/chitosan nanolayers

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

22. Take-home messages Plenty of room for improvement of food nano-systems Need to improve detection/characterization methodsCountless applications in foodsNeed to evaluate impact on healthNeed to evaluate impact on environmentEthical aspects?

23. Thank you for your attention