Food Packaging PDF

FDE 418 Food Packaging : PART I Food Packaging General Definitions Packaging Materials (Plastic ; Glass, Paper ; Metal) Packaging of different Food Categories Modified Atmosphere Packaging (MAP) ; Aseptic Packaging Active & Intelligent Packaging Engineering Design for Food Packages Packaging and F...

FDE 418 Food Packaging : PART I Food Packaging General Definitions Packaging Materials (Plastic ; Glass, Paper ; Metal) Packaging of different Food Categories Modified Atmosphere Packaging (MAP) ; Aseptic Packaging Active & Intelligent Packaging Engineering Design for Food Packages Packaging and Food Safety & Quality ( Migration ; Scalping) Edible Packaging New Trends in Food Packaging Sustainability and Packaging and Legislative Aspects Part I Introduction to Food Packaging Plastic Polymers and Plastic Packaging Materials Food Packaging ❖ Food packaging is of paramount significance to preserve the quality of fresh and processed foods. ❖It would be practically impossible for the food processors to distribute food without packaging. Very few foods are sold unpackaged Food Packaging Good packaging prevents waste and ensures that the food retains its desired quality throughout its shelf life. Is the food packaging unnecessary? Is it a waste of resources or an environmental menace? Such views arise because, by the time most consumers come into contact with a package, its job, in many cases, is almost over. Packaging Functions The several packaging functions include: ✓ physical protection ✓ prevention of spoilage and contamination ✓ preservation of food quality ✓ product information ✓ bring convenience ✓ facilitate transportation as well as distribution. Definition Therefore, food packaging may be defined as: ‘the enclosure of food products in a wrapped pouch, bag, box, tray, can, bottle or any other packaging material with the functions of containment, protection, preservation, communication, utility and performance.’ Packaging may be performed before processing (canning, retort pouch, dairy fermentations, etc.) or can be followed after major processing steps (pasteurization, ultra high temperature (UHT) processing, baking, frying, etc.). Functions of Packaging Containment Protection Convenience Communication Containment The other basic packaging function is to contain food products in specific containers (packages) to facilitate transportation and distribution throughout the supply chain. Keeps food together. It would be impossible to move liquid products without packages. The problems of food without packaging include mixing of graded food stuffs, bruising of soft fruits, physical damage due to friction of loose materials, contamination with air suspended particles, etc. Therefore, packaging reduces the huge loss of food products in the entire product chain.  Protection The deterioration of food is either caused by: ▪ external factors like oxygen, moisture, off flavors, toxins, microorganisms, mass transfer, physical and mechanical damage, or ▪ internal factors like inherent microorganisms. Therefore, the primary function of the package is to: protect the food from adverse effects of environment, retain the beneficial effects of processing, extend the shelf life and maintain the quality and safety of fresh or processed foods. The diversity in composition, structure, and physiology of fresh and processed foods demands varying levels of protection throughout the supply chain. Therefore, the packaging should be aimed to protect the food from physical, chemical, and biological hazards.  Protection Physical protection shields the food from mechanical damage due to shock and vibration during transportation and distribution. Packaging materials like paperboard, corrugated materials, etc. resist impact, abrasion, and crushing damage caused to fruits, eggs, cakes, etc., during transportation. The replacement of glass bottles with plastic packaging material is another example for increasing the physical protection levels to liquid foods. Chemical protection is aimed to reduce the compositional changes caused due to, for example, oxidation, light, and the resulting degradation of color, vitamins, and nutrients. Glass packaging materials, for example, are inert with absolute barrier to substances, but lack protection against light, whereas metal packaging materials act as an absolute barrier but with some migration issues. Plastic packaging materials as commonly used in food packaging show a wide range of different levels of barrier properties. The third role is to protect the food from biological deterioration caused by spoilage and pathogenic microorganisms (bacteria, yeasts, fungi, and viruses), and animals like insects or rodents.  Convenience Industrialization and busy work schedules demand the food and packaging industry to bring convenience to food through innovative packaging solutions. The packaging industry has brought convenience by incorporating features such as easy opening, reclosability and processing in the package via, for example, microwavable packaging, oven safe trays or boil in bags. This has enabled the consumers to prepare food in shorter time, which in turn has increased the global demand for packed food.  Convenience Necessity of modern industrialized societies Food should be apportioned into consumer-sized dimensions. For a product that is not entirely consumed when the package is first opened, the package should be resealable and retain the quality of the product until completely used. The shape (relative proportions) of the primary package with regard to consumer convenience (e.g., easy to hold, open, and pour as appropriate) and efficiency in building into secondary and tertiary packages should be convenient. Product image by the packaging: “The package is the final salesman” Affecting the choice of the customer by: Design Printing Materials used Actions  Communication Each package is labeled to inform the consumers about the product contents, brand, shelf life, and storage conditions. This communication is important to consumers in order to know the product quality, characteristics, and handling, besides assistance in marketing strategies. Several packaging designs are used to accommodate the product information (nutrients, weight, brand labels, certification, ingredient labeling, barcodes, etc.) in order to satisfy the legal requirements and to promote the product branding. Moreover, the package conveys important information on product storage, cooking instructions, price, and life cycle. Communication It enables consumers to instantly recognize products through distinctive shapes, branding, and labeling enables supermarkets to function on a self-service basis. By allowing brands to be created and standardized, it makes advertising meaningful and large-scale distribution possible. Other communication functions of the package include a universal product code (UPC) that can be read accurately and rapidly, serving instructions, and nutritional information on the outside of the package. Packaging Materials A number of packaging materials are currently in use for food applications, which are accepted by regulatory bodies like the United States Food and Drug Administration (FDA), European Union (EU), etc. The packaging design and material properties determine the package end use and shelf life of packaged foods. Glass, paper, metal, and plastics are the most important groups of materials used for food packaging. Packaging Materials Plastics Polyolefins Copolymers of ethylene Substituted olefins Polyesters Polyamides Biobased plastics: Starch, Chitosan, Polylactic acid, Poly(hydroxyalkanoates), Biopolyethylene, Biopolyethylene terephthalate, Regenerated cellulose film Glass Metal Paper  Lipids : Lecithins Lecithin is a generic term to designate any group of yellow-brownish fatty substances occurring in animal and plant tissues composed of phosphoric acid, choline, fatty acids, glycerol, glycolipids, triglycerides, and phospholipids (e.g.,phosphatidylcholine, phosphatidylethanolamine,and phosphatidylinositol). 1 phosphatidylcholine, lecithin 2 Lipids : Lecithins ▪ Lecithin vesicles have recently been used for encapsulation of food enzymes since the formation of lecithin capsules can be achieved under relatively low temperatures. ▪ Could be blended with other coating materials 3 Lipids : Liposomes Liposomes are composed of natural phospholipids, cholesterol and may also contain mixed lipid chains with surfactant properties (e.g., egg phosphatidylethanolamine) The liposome can be used as a vehicle for administration of nutrients and pharmaceutical drugs. Liposomes can be prepared by disrupting biological membranes (such as by sonication). Microfluidization 5  Function of Cholesterol in Liposome Structure Modulates packing of phospholipids Maintains the flexibility of the lipid bilayer Maintains structural integrity Increases liposome stability W/O cholesterol, liposome membrane may easily disrupt Usual cholesterol: phosphatidylcholine ratio is 1:1 to 2:1 Polar group of cholesterol arranged near the polar head of the phospholipid  Lipids : Liposomes Small unilamellar (unicellular) vesicles (SUVs) Large unilamellar vesicles (LUVs) Giant unilamellar vesicles (GUVs) Multilamellar vesicles (MLVs) Multivesicular vesicles (MVVs) 7 Applications of liposome in food, functional food, nutraceutical and bioactive delivery Liposomes Advantages Disadvantages ❖Entrapment of hydrophilic compounds in Chances of leakage the core part Possibility of fusion from SUV to LUV ❖Entrapment of hydrophobic components Oxidation, hydrolysis of phospholipids in the lipid bilayer part Higher physical instability during storage ❖Entrapment of both hydrophilic and hydrophobic compounds High production cost ❖Possibility of surface functionalization Thin film-hydration preparation Thin film-hydration preparation Advantages Disadvantages Simple and most commonly Low encapsulation efficiency used method Difficult to get uniform-sized Generally used to prepare MLV, liposomes but can be converted to SUV, Difficult to scale up LUV Thin film preparation High Pressure Extrusion Method (Membrane Extrusion Method) Polycarbonate filters are used Large-size liposomes are placed in a stainless steel chamber, which contains a membrane at the bottom High pressure is applied on the surface of liposomes with the help of compressed air Liposomes are passed through the small pore of the filters and thus each one is divided into small sizes Used to convert LUV to SUV To convert heterogeneous to homogeneous size liposomes  Sonication Sonicator is the instrument, which produces ultrasonic waves Waves hit the liposomes To reduce the size of liposomes (conversion from MLV to ULV or LUV to SUV) To achieve uniformly sized liposomes To solubilize compounds in liposomes Microemulsion Used to reduce the size of large liposomes into small size Microfluidizer is used Macroliposomes were pumped at very high pressure (10000 psi) through 5 micron orifice Macroliposomes are forced along microchannels, which direct them into two streams of fluid to collide together at the right angle at a very high velocity After single pass size is reduced to 0.1-0.2 micron Novel Techniques (a) Supercritical fluid extractor, (b) Microemulsion (c) Ultrasonication 18 19  Highly stable emulsions can be formed by using high levels of small molecular weight surfactants (SMWS) SMWS approved by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) include: glycerin fatty acid esters, sucrose fatty acid esters, soybean phospholipids, sorbitol anhydride The use of synthetic surfactants in the food industry, however, is limited because of clean labeling requirements, off-flavors, and potential toxicity Other kinds of natural surface-active colloidal molecules have therefore been used as emulsifiers to create food emulsions, including proteins, and polysaccharides These particle-stabilized surfactant-free emulsions are commonly referred to as “Pickering emulsions” Proteins ❑Gelatin ❑Soy protein concentrates/isolates ❑Sodium caseinate ❑Whey protein concentrates/isolates 21 Gelatin ▪ Gelatin is a water-soluble protein derived from collagen and nontoxic ▪ Inexpensive ▪ Commercially available ▪ Good film-forming properties ▪ Gelatin forms thermally reversible gels when warm aqueous suspensions of polypeptides are cooled. ▪ With an aqueous solution of gelatin, the change between the gel and solid state is quite definite. ▪ However, when the gelatin concentration in the aqueous solution is lower than ~1%, definite gelation cannot be observed even by cooling. 22 Blooming Index The Bloom index indicates the gel strength of the gelatin, defined as the weight in grams necessary to apply to the surface of gelatin gel, to produce a 4 mm depth depression. The gelatins have different Bloom numbers (75–100, 175, and 300), with the higher value producing stronger gels  The findings suggested encapsulation of L. acidophilus in alginate/fish gelatin capsule had great potential to improve probiotic bacteria’s survival during baking and storage and to serve as an effective bread enhancer. *Alginate/Fish Gelatin-Encapsulated Lactobacillus acidophilus: A Study on Viability and Technological Quality of Bread during Baking and Storage  VD3 had an almost slow release in the gastric Quickly released from microcapsules under simulated intestinal conditions. Fortification of yogurts with encapsulated VD3 led to an increase in textural parameters where syneresis value decreased and viscosity increased. The number of probiotics in fortified yogurts was also considerably higher than in the control sample. The sensory analyses revealed no major differences between the fortified and control samples Protein-polysaccharide microcapsules were suitable wall materials for VD3 microencapsulation, and these microcapsules could potentially have numerous applications in the food industry. *Gelatin-maltodextrin microcapsules as carriers of vitamin D3 improve textural properties of synbiotic yogurt and extend its probiotics survival Whey Proteins ▪ Water soluble ▪ Requires denaturation for capsule making ▪ Crosslinking ▪ Very stable ▪ Mixed with other polysaccarides 30 Example 31 Whey protein combined with citrate mung starch through spray drying could be a promising strategy to produce microcapsules of poorly water-soluble compounds such as capsaicin. *Fabrication and Characterization of Whey Protein—Citrate Mung Bean Starch—Capsaicin Microcapsules by Spray Drying with Improved Stability and Solubility Other proteins Soy ? Casein ? Pea ?  Ultraturrax (UT) and Ultraturrax+Ultrasound (UT+US). Shear and inertia stress vs acoustic cavitation and power dissipation Soy proteins managed to encapsulate fish oil masking its characteristic odor and oily texture. These microparticles would facilitate fish oil incorporation into healthy food products. *Encapsulation of fish oil in soybean protein particles by emulsification and spray drying  Curcumin, natural polyphenolic compounds isolated from the rhizome of turmeric Dissociation of NaCas in warm aqueous ethanol exposed more hydrophobic regions of caseins for contacting curcumin. The much improved dispersibility after encapsulation improved the reactivity of curcumin, resulting in enhanced biological activity as assessed by antioxidant and cell growth assays. The simple approach used in this work may be used to deliver a variety of lipophilic bioactive compounds to improve the health and wellness of consumers. *Enhanced Dispersibility and Bioactivity of Curcumin by Encapsulation in Casein Nanocapsules  Pea protein isolate (PPI) nanocarriers for lipophilic polyphenols of curcumin (CUR), quercetin (QUE) and resveratrol (RES) Thermodynamic parameters revealed the main hydrophobic interaction and hydrogen bonding were important in their assembly between CUR/QUE and RES with PPI, respectively. Ultraviolet light and thermal stability, antioxidant activity of polyphenols was improved by complexation with PPI. Molecular docking indicated binding energy of legumin with three polyphenols of QUE > RES > CUR, and the binding conformation of polyphenols with its surrounding amino acids in its binding location was visualized. *Pea protein based nanocarriers for lipophilic polyphenols: Spectroscopic analysis, characterization, chemical stability, antioxidant and molecular docking Proteins ▪ Protein-encapsulated tallow and vegetable oils have been applied to produce animal feeds ▪ Proteins can also be used, together with other coating materials, to form microcapsules. ▪ A mixture of protein and carbohydrate has been applied to an encapsulation process of oily substance ▪ Other protein sources ▪ Cricket ▪ Meal worm 38  Water Binding Capacity Total Phenolic Content Oil Binding Capacity HHP Defatting & w/ hexane Conventional FTIR Spectroscopy NMR Relaxometry Protein Content Antioxidant Activity Protein rich Acheta domesticus & Tenebrio molitor powders  Gas Chromatography Total Phenolic Content DSC Grinding HHP Peroxide Value & Conventional Antioxidant Activity w/ hexane Oil Content Oil of Acheta domesticus & Tenebrio molitor The different encapsulation methods and the general structure of the microcapsule. Microencapsulation Techniques Hydrogel Microspheres Solvent Evaporation Spray Drying Spray Cooling/Chilling Fluidized Bed Coating Extrusion Centrifugal Extrusion Lyophilization Coacervation Centrifugal Suspension Separation Cocrystallization Liposome Entrapment Double Emulsions 42 Hydrogel Microspheres ❑ Microspheres made of gel-type polymers, such as alginate, are produced by dissolving the polymer in an aqueous solution ❑ Then, suspending the active ingredient in the mixture ❑ Extruding through a precision device, producing micro droplets ❑ Then fall into a hardening bath that is slowly stirred. The hardening bath usually contain calcium chloride solution. Advantage: The method involves an ―all-aqueous system and avoids residual solvents in microspheres. ❑ The particle size of microspheres can be controlled by: A- using various size extruders or B- by varying the polymer solution flow rates. 43 44  Encapsulation of two fermentation agents in calcium alginate microspheres. Encapsulation does not inhibit the activity of Lactobacillus sakei (LS0296). Release of LS0296 from microspheres is controlled by Fickian diffusion. New microsphere formulations are suitable for use in fermented food production. *Encapsulation of two fermentation agents, Lactobacillus sakei and calcium ions in microspheres Solvent Evaporation 49 Coacervation Coacervation is a physical phenomenon in which a homogeneous colloidal solution separates into two immiscible liquid phases: a colloid- rich phase called coacervate and a colloid-poor phase, driven by specific environmental conditions. One of the best methods for encapsulation of heat-labile agents is complex coacervation process. Formation of a Three-Immiscible Chemical Phase First the core material (usually an oil) is dispersed into a polymer solution (e.g., a cationic aqueous polymer, gelatin) The second polymer (anionic, water soluble, gum arabic) solution is then added to the prepared dispersion. Deposition of the Coating Deposition occurs when the two polymers form a complex This process is triggered by the addition of salt or by changing the pH, temperature or by dilution of the medium. Solidification of the Coating Solidification of the coating is achieved either by thermal, cross-linking, or desolventization techniques, and forms a self-sustaining microcapsule entity 50 Example 51 Physicochemical factors influencing complex coacervation process Limitations regarding the encapsulation of hydrophilic compounds can be overcame by adding double emulsion step at the beginning Double Emulsions 54 55 Making Double Emulsions 56 Application of DE : Mayonnaise 57 Spray Drying ▪ Accounts for the majority of commercial encapsulated materials in food products ▪ Preparation of dry stable food additives, functional ingredients, and flavors. ▪ In principle the volatile flavor compounds evaporate faster than water. ▪ Economical, flexible in that it offers substantial variation in encapsulation matrix, adaptable to commonly used processing equipment, and produces particles of good quality. ▪ Production costs are lower than those associated with most other methods of encapsulation ▪ It is also one of the oldest and well-known encapsulation techniques 58 Spray Dryer 59 Disadvantages of Spray Drying ▪ The equipment is very bulky and with the ancillary equipment is expensive. ▪ The overall thermal efficiency is low, as the large volumes of heated air pass through the chamber without contacting a particle, thus not contributing directly to the drying. ▪ Temperature sensitive materials ▪ Maillard 60 Spray Chilling/Cooling ❑ Coating material is fat ❑ No evaporation ❑ Spray drying employs hot air to volatilize the solvent from a coating dispersion; ❑ Spray cooling and spray chilling use air cooled to ambient or refrigerated temperatures. ❑ The core and lipid wall mixture are atomized in the chilled air that causes the fat to solidify around the core, thereby forming a crude encapsulated product 61 Spray Chilling (Congealing)/Cooling ❑ Capsules are insoluble in water. ❑ Spray Cooling : coating substance is vegetable oil. ❑ The encapsulation material usually has a high melting point, between 45 and 122 ◦C ❑ Spray Chilling : coating substance is fractionated or hydrogenated vegetable oil. ❑ The encapsulating materials have a melting point between 32 and 42 ◦C ❑ For the encapsulation of solid food additives, such as ferrous sulfate, acidulants, vitamins, minerals, and solid flavors, as well as for heat-sensitive materials or those that are not soluble in typical solvents ❑ With the functional food revolution, the importance of spray chill has increased, particularly in the production of functional food ingredients for the primary purpose of fortification. 62 Lyophilization ▪ Lyophilization or freeze drying is a process for the dehydration of almost all heat-sensitive materials, bioactives, and aromas. ▪ Except for the long dehydration period required (commonly 20 h), freeze drying is a simple technique that is particularly suitable for the encapsulation of aromatic materials. ▪ Because the entire dehydration process is carried out at low temperature and low pressure, it is believed that the process should have a high retention of volatile compounds. 63 Liposome Entrapment ❑ Liposomes consist of an aqueous phase that is completely surrounded by a phospholipid-based membrane. ❑ When phospholipids, such as lecithin, are dispersed in an aqueous phase, the liposomes form spontaneously. ❑ One can either have aqueous or lipid-soluble material enclosed in the liposome. ❑ However, liposome entrapment for many flavor compounds is not possible because liposomes will not form for materials that are soluble in both the aqueous and lipid phases ❑ Microfluidization ❑ Ultrasonication ❑ Reverse Phase Evaporation 66 Layer-by-Layer Deposition ▪ Polyelectrolyte layer-by-layer (LbL) assembly has shown promise as a route for fabricating thin films with controlled thickness and designed functionality. ▪ This technique begins with a substrate with an excess surface charge on which alternating layers of polycations and polyanions are deposited by dipping the substrate into a dilute solution of the appropriate polyelectolyte salt. ▪ Thin films incorporating a variety of functionalities have been demonstrated using this technique, due in large part to the fact that the construction of the film is predominantly controlled by electrostatics (hydrophobic interactions may play a role as well). 67 Layer-by-Layer Deposition 68 69 Controlled Release 73 Characterisation Techniques Particle size measurement Dynamic light scattering Laser diffraction Zeta Potential Encapsulation efficiency Release Mathematical Modelling Digestion behavior ( simulated intestinal fluid , gastric fluid) Stability Instant Long Term Microscopy ( Light , SEM , TEM) Rheological characterization Glass transition temperature Antioxidant activity ( DPPH , ABTS , FRAP ) Total phenolic content Antimicrobial activity 75 Encapsulation going on….. Lipids : Waxes ▪ Waxes are important derivatives of higher alcohols, such as C12–C28, which are esterified to long chain fatty acids. ▪ Traditionally, wax coatings have been applied to fresh fruits and vegetables to extend their postharvest storage life. ▪ Waxes are commonly used as lipid coatings for encapsulation of food ingredients, particularly for the encapsulation of water- soluble ingredients. ▪ Edible waxes are significantly more resistant to moisture transport than most other lipid or nonlipid coatings. One of beeswax’s primary esters (myricyl palmitate) Fatty esters of Waxes 3 The major groups of compounds found in beeswax are alkanes, free fatty acids, monoesters, diesters, and hydroxy-monoesters. Fatty alcohols and hydroxy-diesters are minor constituents. Effect of edible emulsion coatings on strawberries and apples. (a) Time-lapse photographs of bare and coated (i) strawberries and (ii) flesh-cut apples over 7 days. (b) Water weight loss of (i) strawberries and (ii) flesh-cut apples over 7 days, and (c) comparison between stiffness of bare and coated (i) strawberries and (ii) flesh-cut apples. Shellac is primarily used for coating chocolate goods like candy-covered raisins and nuts. Besides, it is also applied as a covering on certain nutritional supplements and coffee beans. Carnauba wax comes from the leaves of the carnauba palm, which grows in northeastern Brazil. Treatments Coating conditions Solid content of coating T1 Synthesized carnauba wax emulsion without organoclay 16.8% T2 Synthesized organoclay (0.5 w%) carnauba wax emulsion 16.8% T3 Synthesized organoclay (1 w%) carnauba wax emulsion 16.8% T4 Commercial wax 1 17.1% T5 Commercial wax 2 17.6% T6 Uncoated (control) – 7  Lipids : Lecithins Lecithin is a generic term to designate any group of yellow-brownish fatty substances occurring in animal and plant tissues composed of phosphoric acid, choline, fatty acids, glycerol, glycolipids, triglycerides, and phospholipids (e.g.,phosphatidylcholine, phosphatidylethanolamine,and phosphatidylinositol). 8 phosphatidylcholine, lecithin 10 Lipids : Lecithins ▪ Lecithin vesicles have recently been used for encapsulation of food enzymes since the formation of lecithin capsules can be achieved under relatively low temperatures. ▪ Could be blended with other coating materials 11 Lipids : Liposomes Liposomes are composed of natural phospholipids, and may also contain mixed lipid chains with surfactant properties (e.g., egg phosphatidylethanolamine) The liposome can be used as a vehicle for administration of nutrients and pharmaceutical drugs. Liposomes can be prepared by disrupting biological membranes (such as by sonication). Microfluidization 12 Applications of liposome in food, functional food, nutraceutical and bioactive delivery Thin film preparation Novel Techniques (a) Supercritical fluid extractor, (b) Microfluidizer (c) Ultrasonicator 17 18