Polymeric Food Packaging Material's

1. Introduction: Packaging has been with humans for thousands of years in one form or the other. Packaging dates back to when people first started moving from place to place. Originally, skins, leaves, and bark were used for food transport. Four thousand years ago, sealed pottery jars were used to protect against rodents, and glass making was an important industry in Egypt. Tin-plating iron became possible in AD1200, and as steel replaced iron this method became useful. One hundred years ago there was little use for packaging in the food industries. Now, tremendous progress has been made in the development of diversified packaging materials and packaging equipment.
2. Packaging performs five main functions:
a. Product containment
b. Preservation and quality
c. Presentation and convenience
d. Protection during Distribution and Processing
e. Provide storage history
3. Ideal packaging material: Packaging material with zero toxicity, high product visibility, strong marketing appeal, the ability of moisture over a large temperature range, low cost and availability, stable performance over a large temperature range, suitable mechanical strength and suitable strength, easy machine handling and suitable friction coefficient, closure characteristics, such as opening, sealing and resealing, ability to include proper labeling, the resistance of migration of leaching from the package, protection from loss of flavor and odor, and control transmission of required or unwanted gases, etc.
4. Packaging material selection is based on:
Technical properties (strength, flexibility, etc.), fitness for purpose (moisture barrier, cushioning, etc.), availability, manufacturing capability, cost, environmental impact, and regulations.
5.Types of Packaging Materials :
a. Rigid (wood, glass, metals, and hard plastics )
b. Flexible (Plastic film, foil, paper, and textiles )
6. Industrial Overview:
Packaging is one of the fastest-growing industries and stands at USD 700 billion globally. The Indian packaging industry constitutes ~4% of the global packaging industry and is growing 18% p.a. wherein flexible and rigid packing is expected to grow at 25% and 15% respectively. The per capita packaging consumption in India is low at 4.3 kgs, compared to developed countries like Germany and Taiwan where it is 42 kgs and 19 kgs respectively. Indian packaging industry is valued at over USD 32 Bn and offers employment to more than 10 lakh people across the country through ~10,000 firms.
7. Polymeric packaging material:
a. Plastic: It is a complex organic compounds produced by polymerization, capable of being molded, extruded, cast into various shapes and films, or drawn into filaments and then used as textile fibers.
7.1. Based on the polymerization process and molecular structure, Polymeric materials are classified into various polymers.
8. Testing of polymeric Packaging Materials

1. (Polymeric food packaging material’s) Food Packaging Material Presented by : Prakash Kumar (Ph.D. Research Scholar, AGFE, IIT- Kharagpur ) [email protected]

2. Packaging has been with humans for thousands of years in one form or the other. Packaging dates back to when people first started moving from place to place. Originally, skins, leaves, and bark were used for food transport. Four thousand years ago, sealed pottery jars were used to protect against rodents, and glass making was an important industry in Egypt. INTRODUCTION : “ Packaging Material”

3. One hundred years ago there was little use for packaging in the food industries. Now, tremendous progress has been made in the development of diversified packaging materials and in the packaging equipment. Tin-plating iron became possible in AD1200, and as steel replaced iron this method became useful.

4. Packaging performs five main functions: Product containment Preservation and quality Presentation and convenience Protection during Distribution and Processing Provide storage history

5. Ideal packaging material: Zero toxicity High product visibility Strong marketing appeal Ability of moisture over a large temperature range Low cost and availability Stable performance over a large temperature range Suitable mechanical strength and suitable strength Easy machine handling and suitable friction coefficient Closure characteristics, such as opening, sealing and resealing Ability to include proper labeling Resistance of migration of leaching from package Protection from loss of flavor and odor Controlled transmission of required or unwanted gases etc.

6. Packaging material selection is based on: technical properties (strength, flexibility, etc.) fitness for purpose (moisture barrier, cushioning, etc.) availability manufacturing capability cost environmental impact regulations

7. Types of Packaging Materials : From skins, leaves, and bark, tremendous progress has been made in the development of diversified packaging materials and in the packaging equipment. In general, Packaging Materials may be grouped into : 1- rigid (wood, glass, metals, and hard plastics ) 2-flexible ( Plastic film , foil, paper, and textiles )

8. INDUSTRY OVERVIEW (Reference : A Report on Plastic Industry (Jan,2016) by FICCI with knowledge and strategic partner TATA Strategic Management Group. ) Packaging is one of the fastest growing industries and stands at USD 700 billion globally. The Indian packaging industry constitutes ~4% of the global packaging industry and which is growing 18% p.a. wherein flexible and rigid packing is expected to grow at 25% and 15% respectively. The per capita packaging consumption in India is low at 4.3 kgs , compared to developed countries like Germany and Taiwan where it is 42 kgs and 19 kgs respectively. Indian packaging industry is valued at over USD 32 Bn and offers employment to more than 10 lakh people across the country through ~10,000 firms.

9. Packaging in general is classified into two significant types i.e. Rigid Packaging and Flexible Packaging. Estimated

10. Polymeric Packaging Material

11. Webster’s dictionary definition : It is a complex organic compounds produced by polymerization, capable of being molded, extruded, cast into various shapes and films, or drawn into filaments and then used as textile fibers. Composed primarily of a binder with : Plasticizers Fillers Pigments Other additives What is plastic?

12. Why plastic? A wide variety of different qualities : -Rigid V/s Flexible -clear V/s opaque Light weight – high product to package ratio. Cost Inert Chemically resistant

13. Based on polymerization process and molecular structure, Polymeric materials classified into : Polyolefins – Polyethylene and Polypropylene (PP) Polyvinyl group - Polyvinyl Chloride (PVC) Condensation – Polyester (PET), Nylon-6 or Polyamide (PA) Styrene Polymers – Polystyrene (PS) and Expanded polystyrene (EPS) Carbonate group – Polycarbonate (PC) Ethylene vinyl alcohol Coated films Laminated films Coextruded films

14. a. Polyolefins – flexibility, strength, lightness, stability, moisture and chemical resistance and easy processability and are suited for recycling and reuse . POLYETHYLENE : LDPE (Low-Density Polyethylene) LLDPE (Linear LDPE) MDPE (Medium DPE) HDPE (High DPE ) HMHDPE (High Molecular High DPE ) POLYPROPYLENE : Physical Properties Durable High elongation 300% High Tensile Strength 4500 psi High Yield Strength 4000 psi High Melting point Low Density Lowest density of all plastics used in packaging

15. b. Polyvinyl Chloride (PVC) Hard Brittle Transparent material Low GTR Moderate WVTR Good resistance to fat and oil Glass like clarity contains twice amount Good mechanical strength of Chlorine as PVC Retention of flavor Resistance to chemicals Excellent printability Lower weight/volume ratio Polyvinylidene chloride: excellent barrier to water vapor, gases, and fatty and oily products. E.g. poultry, cured meats, cheese, snack foods ,tea, coffee and confectionary product packaging

16. c. Condensation polymer: formed from ester monomers that result from the reaction between carboxylic acid and alcohol or condensation reaction b/w diamine and diacid (repeating unit held by amide link) Polyester : Gloss, low gas and moisture permeability, high mechanical strength, light weight, chemically not react etc. PET or PETE: Glass like transparency, good resistance to heat, oils, solvent and acids but not to bases . E.g., Bottles, jars, tubes, trays, bags and snack food wrappers It exists both as Amorphous and a semi-crystalline form. Polyethylene napthalate: It having high glass transition temperature and it is far more better than PET but more costly nearly 3 to 4 times. Eg . Beer etc

17. Polyamide or Nylon-6 : Formed by a condensation reaction between diamine and diacid and the repeating units are held together by amide links. E.g. Nylon-6 Used in packaging, high mechanical strength, high elongation capability, excellent resistance to cutting, perforation, abrasion and bursting, high chemical resistance to oils and fats, it has mechanical and thermal properties similar to PET.

18. d. Styrene polymers : Polystyrene (PS ) : It is not flexible like LDPE and PP. It is hard in nature Properties: Rigidity and dimensional stability. Resistance to chemicals Easy processing Good barrier to moisture and ability to take post moulding decorations Expanded polystyrene( EPS) it is neither flexible nor rigid. It’s cushioning in nature. Commonly known as “ thermocole ”. Properties : Densities varies from 20-30kg/cm3 Stresses at 10% compression is 1 to 1.4 kg/cm2. Tensile strength is from 2.5 to 3.2 kg/cm2. Thermal conductivity at 100 ⁰C is 0.028 k.cal.m /hr.m2 Does not provide breeding ground for fungi, bacteria or insects

19. e. Carbonate group : Polycarbonate is formed by polymerization of a sodium salt of bisphenol acid with carbonyl dichloride (phosgene). Properties : Clear Heat resistance Durable It is mainly used as a replacement for glass in items such as large returnable/refillable water bottles and sterilizable baby bottles. caution!! harsh detergents such as sodium hypochlorite is not recommended because they catalyze the release of bisphenol A

20. f. Ethylene vinyl alcohol (EVOH): It is copolymer of ethylene and vinyl alcohol. It is an excellent barrier to oil, fat and oxygen. It is moisture sensitive and is thus mostly used in multilayered co-extruded films in situation where it is not in direct contact with liquids. EVOH

21. g. Coated films : Films are coated with other polymers or aluminum to improve the barrier properties or to import heat stability. nitrocellulose coating. vinyl acetate or vinyl chloride coating. Aluminum coating. Properties : Sleeves of this materials are tough. Stretchable Permeable to air, smoke and moisture. (packaging meat before smoking and cooking)

22. h. Laminated films : Two or more materials (plastic/paper/aluminum) are laminated together to improve the barrier properties of the packaging material. Bonding is commonly achieved by use of water, solvent or solids based adhesives. Printing buried between layers and thus not subject to abrasion.

23. Types of laminates Food application Polyvinylidene Chloride coated polypropylene ( 2 layers) Crisps, snack foods, confectionery, ice cream, biscuits, chocolate Polyvinylidene chloride coated polypropylene polyethylene Bakery products, cheese, confectionery, dried fruit, frozen vegetables Cellulose-polyethylene -cellulose Pies, crusty bread, bacon, coffee, cooked meats, cheese Cellulose-acetate-paper-foil-polyethylene Dried soups Metallised polyester-polyethylene Coffee, dried milk Polyethylene- aluminium -paper Dried soup, dried vegetables, chocolate

24. i . Coextruded films : Simultaneous extrusion of two or more layers of different polymers. Properties: Very high barrier properties. They are thinner than laminates. The layer do not separate. lower cost.

25. Types of coextrusion Food application High impact polystyrene-polyethylene terephthalate Margarine, butter cubs/tubs Polystyrene-polystyrene- polyvinylidene chloride -polystyrene Juices, milk bottles Polystyrene-polystyrene- polyvinylidene chloride-polyethylene Butter, cheese, margarine, coffee, mayonnaise, sauce tubs and bottles

26. Testing of polymeric Packaging Material : Thickness test (mm) Tear strength test Heat seal strength test Bursting strength test (unit : psi) Tensile Strength test {unit : lb/(width or thickness)} & Elongation test (unit : %) Gas transmission test (unit : cc/100 in^2 /24hrs) Water vapour transmission test (unit : grams/100 in^2/24hrs) Grease resistance test (time i.e. min. or hrs, required for 1 st appearance of stain on the packaging material. Aging test

27. References : Report on “Plastic Industries” 2016 by FICCI with help of knowledge and strategic partner TATA strategic and managemet group. Galić , K., Ščetar , M., & Kurek , M. (2011). The benefits of processing and packaging.  Trends in Food Science & Technology ,  22 (2-3), 127-137. Mahalik , N. P., & Nambiar , A. N. (2010). Trends in food packaging and manufacturing systems and technology.  Trends in food science & technology ,  21 (3), 117-128. Kadoya , T. (Ed.). (2012).  Food packaging . Academic Press. Berger, K. R. (2003). A brief history of packaging.  EDIS ,  2003 (17).