NanoPackSafer – um novo sistema de embalagem de alimentos António A. Vicente Departamento de Engenharia Biológica [email protected] Universidade do.

NanoPackSafer – um novo sistema de embalagem de alimentos

António A. Vicente

Departamento de Engenharia Biológica

[email protected]

Universidade do Minho

Instituto para a Biotecnologia e a Bioengenharia

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.

Nanotechnology

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

Nanotechnology

According to the US Food and Drug Administration (FDA):

Functionality

Motivation

Consumers

Environment

All bio-materials from renewable sources

All food-grade, edible materials

Nano-sized systems

Ethical aspects

Nano-engineered films and coatings- Clay nanoparticles

Nano-engineered films and coatingsNano-engineered films and coatings- Clay nanoparticles


Nano-engineered films and coatingsFrom Macro to Micro to Nano- Can you see me?

Can

you

see

me?

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 coatingsNanotechnology – the promise of a food revolution

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

Alginate layers

Chitosan layers


11

Characterization of the nanolayered film

Films Thickness (µm)

WVP x 1011

(g.m-1.s-1.Pa-1)Improved

barrierO2P x 1014

(g.m.Pa-1.s-1.m-2)

Improved barrier

Aminolyzed PET

103.00 1.42 ± 0.39 --------- 2.50 ± 0.03 --------

PET + 5 layers

103.27 1.08 ± 0.10 --------- 2.12 ± 0.03 --------

5 layers 0.27 0.019 ± 0.005

--------- 0.069 ± 0.006 --------

Pectin1 100-150 61.9 ± 5.6 14.2 % ------------ ---------

Chitosan2 45-50 8.60 ± 0.14 38.9 % 7.12 ± 0.23 170 %

Gas barrier properties

1 Hoagland and Parris (1996). Journal of Agricultural and Food Chemistry, 44, 1915-19192 Fajardo et al. (2010). Journal of Food Engineering.


aminolyzed PET

Positively Charged:0.2 % chitosan, pH 3 or 0.3 % of Methylene Blue, pH 7

water water

-carrageenan/chitosan nanolayered film with a model compound

(Methylene Blue) incorporated on the 2nd, 4th or 6th layer

Negatively Charged:0.2 % -carrageenan pH 7

+++

++- -

- ---

0

5

10

15

20

25

30

0 500 1000 1500

Adso

rptio

n (u

g/cm

2 )

Time (s)

MB in second layer

MB in fourth layer

MB in sixth layer

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

400 450 500 550 600 650 700

Abs

orba

nce

Wavelength (nm)

MB in second layer

MB in fourth layer

MB in sixth layer

UV-VIS spectroscopy, 190-

800 nm

Real time deposition Quartz Crystal Microbalance

Release from chitosan nanolayered films in liquid medium

Nanolayered films with MB in the:

2nd Layer

4th Layer

6th 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


Nanolayered films with MB in the 6th Layer


0

0,2

0,4

0,6

0,8

1

1,2

-20 60 140 220 300 380

Mt/M

∞

time (min)

ExperimentalEq. 1Eq. 2

0

0,5

-15 -5 5 15

Fick´s transport

Anomalous behaviour – Fick + 1 main reconfiguration

ok


Nanolayered films with MB in the 2nd and 4th Layers


Fick´s transport


pH=7

+ + + + + + + + ++- - - - - - - - - - -

+ + + + + + + + ++- - - - - - - - - - -

Strong electrochemical interaction - affects the transport mechanism, which cannot be described by neither Fickian nor anomalous behaviour

+ + + + + + + + ++

+ + + + + + + + +++ + + + + + + + ++

+ + + + + + + + ++

Fick´s transport


pH=2

ok

“Normal” interaction -behaves as a “macro” polymeric network


Application on mangoes

Contact angle

Applications

Application on mangoes – Shelf-life analysis

Weight loss

The pectin/chitosan nanolayers reduced the weight loss of the mangoes.

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

Applications

Applications

Application on mangoes – Appearance after 45 days

Without coating

With pectin/chitosan

nanolayers

Application on pears – Appearance after 7 days of refrigerated storage

Applications

21

Take-home messages

Plenty of room for improvement of food nano-systems

Need to improve detection/characterization methods

Countless applications in foods

Need to evaluate impact on health

Need to evaluate impact on environment

Ethical aspects?

Thank you for your attention

NanoPackSafer – um novo sistema de embalagem de alimentos António A. Vicente Departamento de Engenharia Biológica [email protected] Universidade do.

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