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Active Packaging Antimicrobial Films for Food Packaging
Dr. Selcuk Yildirim
Institut fr Getrnke und Lebensmittel Innovation Life Sciences und Facility Management
Content
Packaging and ist functions
Active packaging
Antimicrobial films & packaging systems
Natural antimicrobial agents
Design of antimicrobial systems
Summary & outlook
Packaging and ist functions
Packaging: A coordinated system of preparing goods for transport, distribution, storage, retailing and use..
Marketing functions Technical functions
Information Contain
Display Transport
Communicate Protect
Convenience Preservation
End of life
Preservation of Food
Passive Role (barrier)
Food
O2
microorganism
chemicals
water vapour
light
Consumer trends - better quality, - Freshness - convenience
New packaging technologies
- shelf life extention - food lost - safe food
Active Packaging
Active Packaging: ..designed to deliberately incorporate components that would release or absorb substances into or from the packaged food or the
environment surrounding the food Regulation (EC) No 1935/2004
*
* Yildirim S. Newsletter Transfer, 3-2010, Wdenswil, Switzerland
Active layer
Food
Active Scavenging Systems - Oxygen - CO2 - Moisture - Ethylene - Odor
Active Releasing Systems - Antimicrobial agent
- CO2 - Antioxidant
- Flavours - Ethylene
Barrier layer
Antimicrobial Packaging
A complimentary method to the existing preservation methods to control undesirable microorganisms on foods
Direct addition of antimicrobials could result in some loss of their activities because of their diffusion into the food matrix*
Use of packaging films containing antimicrobial agents could be more efficient than the direct addition of these compounds into the food
Controlled migration of the active compound from the packaging material into the food enable not only the initial inhibition of undesirable microorganisms present in food, but also create a residual activity over time, during transport, storage and distribution of food**
* Han J H and Floros J D (1997), Casting antimicrobial packaging films and measuring their physical properties and antimicrobial activity, J. of Plast. Film & Sheeting, 13, 287-298. ** Cutter C N (2002), Microbial control by packaging: A review, Crit. Rev. Food Sci. Nutr., 42, 151-161
Antimicrobial Packaging Systems
* Yildirim S. Active Packaging for Food Biopreservation in Protective cultures, antimicrobial metabolites and bacteriophages for food and beverage biopreservation, Ed. Christophe Lacroix, Woodhead, 2011
Food
Barrier layer
Active layer
Antimicrobial agents
Food
Antimicrobial agents
Food
Antimicrobial agents
Barrier layer
Active layer
Barrier layer
Active layer
*
Natural Antimicrobial Agents
Natural antimicrobial agents occur in nature or isolated from microbial, plant, or animal sources.
Antimicrobial agents produced by microorganisms include bacteriocins such as nisin or pediocin antibiotics such as natamycin organic acids such as sorbic and benzoic acids enzymes such as lysozyme
Plant origin antimicrobial agents include extracts of spices such as thyme, oregano etc..
Chitosan is an example of natural antimicrobial polymer obtained by deacetylation of chitin obtained commercially from shrimp and crabshell.
Bacteriocins
Bacteriocins are antimicrobial peptides produced by bacteria which inhibit other closely related bacteria.
Nisin is the most common bacteriocin, tested for many applications.* It has been approved for use as a food preservative and was affirmed
GRAS by FDA.
It is non-toxic, heat stable, commercially available and already used for specific applications in a variety of foods
Broader spectrum of antimicrobial activity, including spoilage bacteria and food pathogen.
* Delves-Broughton, J. Nisin, natamycin and other commercial fermentates used in food biopreservation in Protective cultures, antimicrobial metabolites and bacteriophages for food and beverage biopreservation, Ed. Christophe Lacroix, Woodhead, 2011
Bacteriocins Bacteriocin Packaging Material Food/Media Microorganism
Nisin
Pediocin
Enterocin
Lacticin
Polyolefins/MC/HPM
WPI coated PP
LDPE, PE
Paper board with AP
Pectin/PLA composite
Cellophane
Tofu
Hot dogs
Beef
Milk
Orange juice
Liquid egg
Water
Frankfurter
Ham
Turkey brest
Cheese
Smoked salmon
L. monocytogenes,
L. plantarum
B. thermosphacta
L. helveticus
Carnobacterium spp.
LAB
TAB
Yeast
* Yildirim S. Active Packaging for Food Biopreservation in Protective cultures, antimicrobial metabolites and bacteriophages for food and beverage biopreservation, Ed. Christophe Lacroix, Woodhead, 2011
*
Organic Acids, their salts and anhydrides
AMA Packaging Material
Food/Media Microorganism
Sorbic Acid Benzoic acid Acetic acid Propionic acid Their salts and anhyrides
PVDC MC LDPE, PE Chitosan
Beef Cheese Ham
L. monocytogenes, Penicillum sp. A. niger Enterobacteriaceae L. Sakei Molds
Organic acids are natural constituents of many foods and they have been used for a long time as additives in food preservation
They show none-specific antimicrobial properties against bacteria and fungi. Direct surface application by spraying or dipping may result in reduce or loss of
antimicrobial activity due to a possible reaction with food components, diffusion into the food, and evaporation or instability during food processes.
A more effective way could be the incorporation of organic acids into the packaging followed by release to food which may result in longer term protection of the food.
Packaging films containing organic acids should have a direct contact with the food in order to release the active compounds to the food surface.
Antimicrobial activity of organic acids depends on the dissociation constant pKa
Plant extracts
AMA Packaging Material
Food/Media Microorganism
Cinnamaldehyde Rosemary oil Grapefruit seed extract Linaolol Eugenol, tymol, menthol Oregano oil
SPI coated OPP/PE PE LDPE, PP OPP WPI
Sprouts Beef Ground beef Cheese Grapes
E. Coli Salmonella E. Sakazaki B. Cereus S. Aureus L. Innocua Yeasts Molds TVC
Spice and herbs are important source of antimicrobial agents which are effective against several gram-positive and gram-negative bacteria as well as yeast and fungi
The composition, structure as well as functional groups of the oils play an important role in determining their antimicrobial activity.
Majority of the natural extracts such as essential oils are approved as GRAS by U.S. Food and Drug Administration
Application of essential oils in packaging for food can be limited with their strong flavours.
Enzymes
ILGI
Lysozyme is an antimicrobial enzyme active on beta 1-4 glycosidic bonds between N-acetylmuramic acid and N-acetylglucosamine of the bacterial peptidoglycan.
Antimicrobial activity on gram-positive bacteria but not on gram-negative bacteria because of their protective outer membrane surrounding the peptidoglycan layer.
Micrococcus lysodeikticus, Alicyclobacillus acidoterrestris Glucose oxidase itself does not possess antimicrobial activity, but the products
from the reaction exhibit antimicrobial power.
Glucose oxidases the formation of H2O2 and D-glucono--lactone, which then reacts with H2O to form D-gluconic acid.
The antimicrobial activity of the system is due to the cytotoxicity of the H2O2 formed, although the lowering of pH by the production of D-gluconic acid may also
influence the growth of some microorganisms
Escherichia coli and Bacillus subtilis Limitations: High cost, requirement of glucose, stability of enzyme activity, low
tolrance of enzymes to high temperature.
Chemical agents
According to the EU regulations (Commission regulation (EC) No 450/2009) active agents that are incorporated into the packaging material to be released into the food
should comply the legislation on food additives.
Chemical antimicrobial agents that are released from the packaging into the food or its environment should be food grade chemicals.
Non-food grade chemicals can be incorporated into packaging if they are not released into the food (specific migrations).
Fungicides such as imazalil and benomyl
Silver in polymers as an antimicrobial agent
Several silver-ion containing zeolite or glass systems have been incorporated into many polymers, such as polyethylene, polypropylene, and polyamide and become
commercially available
Design of Antimicrobial Systems
Development and design of an efficient antimicrobial packaging requires an interdisciplinary approach which involves advances in food technology, microbiology,
biotechnology, chemistry and packaging and material sciences.
Antimicrobial agent should be selected carefully according to several issues
An appropriate incorporation method should be developed according to the selected antimicrobial agent and food application.
Regulatory requirements, cost and quality control issues should be taken into consideration for a successful introduction of the antimicrobial films on the market
Design of Antimicrobial Systems Appropriate antimicrobial agent
Source Natural, chemical
Antimicrobial spectrum Gram-positive, gram negative, yeasts, molds, specific bacteria
Antimicrobial activity Required antimicrobial activity, microbial load on food, shelf life of food Stability of activity
Stability of antimicrobial agents Inactivation of antimicrobial agents by food components, dilution of antimicrobial agent in food, loss of activity due to the storage conditions
Effect of antimicrobial activity on the organoleptic properties of food
Color, Texture, flavour
Impacts of antimicrobial packaging on environment
Production of AM agents, incorporation process, diposal of packaging, recyclability
Design of Antimicrobial Systems Incorporation of antimicrobial agents
Incompatibility Incompatibility with packaging
Incorporation process Extrusion, coating, immobilization
Stability of AMA during processing
Heat, chemical reaction, mechanical energy input
Contamination of process environment
Contamination of machines and materials
Mass transfer of antimicrobial agent
Diffusion of AMA through the film, release rate of AMA from the packaging
Effects of AMA on the properties of the packaging film
Physical and Mechanical properties
Barrier properties, Stiffness, tensile strength, coefficient of friction, sealing and pealing properties
Design of Antimicrobial Systems Regulatory requirements
Legislation on packaging and food
Active packaging regulations, legislation of food additives, specific migration limitations
Quality controll
Stability of AMA during supply chain
Storage, transportation, retailers
Quality control systems QC after production, converting process and at food packers
Cost
Material cost Cost of AMA, packaging, processing material
Production cost Cost of production of AMA, economy of scale, requirements of investments
Antimicrobial agent
Incorporation method
AM agent - packaging interactions
Regulatory requirements
Quality Control
Cost
Summary & Outlook Incorporation of AMA into packaging is an interesting development, which allows to combine
the preservative function of antimicrobials with the protective function of packaging
Natural antimicrobial agents have high potential for commercial food packaging applications and would be preferred by the consumers to produce safer food
There is still a big gap between research and commercial applications
AMA of packaging systems have been mainly tested with laboratory media, with only few studies carried out with food systems
To demonstrate the real potential of natural AMA for packaging applications, their AMA should be proven with food systems under real storage and distribution conditions
Additional to the antimicrobial functionality, antimicrobial packaging should fulfil several technical, economical, marketing and regulatory requirements.
Interdisciplinary approach is necessary to support further developments in this area
Collaborative research activities between research institutes and food and packaging companies will pave the way for future commercial applications.
Research Areas of Center of Food Tehnology and Process Engineering @ ZHAW
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Active Packaging
- Antimicrobial films
- Oxygen Scavengers
- Ethylene Scavengers
- Moisture Scavengers
New Packaging Processes
- Modified atmosphere packaging
- Equilibrium atmosphere packaging
- Aseptic packaging
Packaging in Food Processing
- Integration of packaging in food processing
Packaging Simulations
- Shelf life simulations
- Packaging material simulations
Thank you for your attention
Dr. Selcuk Yildirim Institut fr Lebensmittel- und Getrnkeinnovation
Campus Reidbach Postfach Wdenswil
selcuk.yildirim@zhaw.ch Tel: +41 58 934 56 31
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