Lesson- 16 Role of Ideal packaging materials
Packaging provides quality and quantity assurance besides creating hygienic environment for food product. It offers security through tamper proof designs and contributes to the product image through structural and graphical design. Food safety is permanent importance as package products against biological, chemical and distribution damages. The primary objective or packaging is to protect the contents during storage, transportation and distribution against deterioration. It may be physical, chemical or biological. According to Robertson (1992), packaging as the enclosure of the products, items or packages in a wrapped pouch, bag, box, cup, tray, can, tube, bottle or other containers to perform the various functions, i.e. containment, protection, information, promotion, etc.
Packaging of food serves many purposes such as providing effective protection to package foods against external contamination from environment; preserving the quality of food. It is one of the most important parameters that sale the product and also a communication device to provide detailed information about the product like, contents, ingredients, notional values, cooking instruction, packaging and expiry dates, etc. generally packaging material s are lighter in weight, easier to open, reseal and store, ensure safe transport and distribution, protect the product from adverse effects such as heat, cold, moisture, etc.
16.1. Properties of Ideal packaging materials
An ideal packaging material should have following qualities:
It should contain the content within it
It should not affect the flavor of the product packaged it
Stable performance over large range of temperature.
Adequate compulsive strength and sufficient impact and puncture strength.
Sufficient thickness of cushioning materials with sufficient ventilation, space for rapid cooling of product.
Protect the product from O2, moisture and light.
Protection of the content form adulterations.
Closure characteristics such as opening, sealing, resealing and pouring.
Low cost and availability.
It should non-toxic in nature.
Proper labeling, storing, marketing appeal to sale, etc.
16.2. Requirement of food packaging
Protection of the product means that there must be a resistance to both internal and external corrosion, with effective properties that guarantee resistance to gas, oxygen, water and smells. Packaging must be safe, it must be impregnable and have safeguards in place to show that it has not been tampered with much of consumer confidence in the products they buy derives from the knowledge that the product has not been opened or tampered with, as seen through the existence of visible seals on products such as the mango juice carton. Packaging is vital to conserve the product. In industrialized countries only 2% of products are spoilt when they reach the consumer compared with a staggering 30-50% in developing countries, where the packaging chain is less well developed. Packaging must meet consumer requirements that products are not just kept in top condition but that they are kept fresher for longer. Packaging also performs overtly technical functions, displaying what the product actually is and information regarding the product, as well as creating brand awareness. Consumer demands and legislative requirements mean that information contained on packaging has become far more specific, for example, detailing the origin and composition of the product. Packaging is also the spokesperson for the manufacturer of the product. The package is the interface between the maker and consumer and therefore must present a desirable image.
16.3. Purpose of Packaging
In addition to the direct approach to food preservation, such as drying and freezing, other measures such as packaging and quality management tools need to be implemented in the process to avoid contamination or recontamination. Although these measures are not preservation techniques, they can play an important role in producing high-quality safe food. Packaging performs five main functions i.e. Product containment, preservation and quality, presentation and convenience, protection, and provide storage history.
16.3.1. Product Containment
The first function of packaging is its capability of containment. The primary purposes of packaging are containment and protection. It is self-explanatory; liquids, semi-liquids, and powders, as well as bulk solids, cannot be marketed without suitable containers. According to the size of the package, different amounts of the product can be delivered to consumers suiting their choice and convenience . In certain circumstances, quantification is mandatory, as in the case of medical pills or capsules that are marketed individually in a blister-type package. Containment refers to holding goods in a form suitable for transport, whereas protection refers to safekeeping goods in a way that prevents significant quality deterioration.
16.3.2. Preservation by Maintaining Quality
The second function of packaging is to control the local environmental conditions to enhance storage life and safety. The main purpose of food packaging is to protect the product from surroundings and maintain the quality of the food throughout the product’s shelf life. One means of spreading the product availability over time is by the proper use of packaging. Product shelf life is controlled by three factors: product characteristics, properties, and storage and distribution conditions of individual package. Reactions causing deterioration in foods include enzymatic, chemical, physical, and microbiological changes. Additional problems include insects, pests, and rodents.
16.3.3. Presentation and Convenience
The third function is the presentation and convenience. In many cases, these are most important factors to the consumers.
Food labels are intended by law to provide the information that consumers need to be able to make the necessary decisions about those purchases of food. It is important to display the product in an attractive manner to the potential buyer. A cleverly designed and beautifully produced packaging can help sell a product, which is an essential ingredient of an effective marketing campaign. The packaging helps in distinguishing products on the shelf, which is a trait especially important when marketing low-fat or nutritional products. Furthermore, packaging must address communication, legal, and commercial demands. For a package to be effective, it must present the product well and should do its own publicity. The protective packaging may have flaps that can be opened to give a ready-made display for the product, whereas some stores may remove the protective packaging to display the product directly on the shelves, leading to a preference for rectangular containers. The clarity (haze) and gloss optical characteristics are important in packaging presentation.
In many cases, packaging provides convenience to the consumers, for example, paper carton for milk or juice with an ease-open and easy-pour cap, thus can also increase consumption. Changes in society, such as diminishing population pattern, increasing average age, smaller families, more leisure time, as well as improvements in the quality of life, standard of living, and general level of education, may also demand specific function of packaging. Eating styles, such as ready-to-eat meals, snacks, and microwaveable ready meals, have been changed over the years, which need innovation in packaging. For children, the packaging might represent innovation or fun. Today’s consumer wants to buy food that is ready to eat, or needs a minimum of preparation, and is good value for money. With microwave food preparation increasing, there is a need for the packaging industry to confront the particular problems in designing packages that deliver microwave products to the dinner table. Food processors can accelerate the usage of microwave ovens by designing products and packages that use the phenomenon of microwave heating/cooking to provide quality. Two types of materials, transparent to microwave and reflective to microwave, can affect the cooking. The transparent materials are nonmetallic substances, such as ceramics, that are coated or filled with microwave absorbent materials. The reflective category is composed of all devices that are metallic and absorb heat. Packaging should meet the future demand of meeting eating style of the society. Other conveniences could be ease of opening, smaller portions, enclosable, and tamper-proof methods. Consumers want tamper-evident closures to avoid packaging being opened unnoticed. In general, tamper-proof packaging makes products more difficult to open, so there is clearly a need to balance safety with consumer accessibility. The tamper-resistant package is to alert the consumer that tampering has taken place and provide visible evidence of tampering. In many cases, consumers are ready to pay more for tamper-resistant packaging. Value-added packaging allows in-package cooking and facilitates on-the-go consumption. Self-heating containers are also being developed for the convenience of consumers, who do not need to reheat the product during consumption.
16.3.4. Protection during Distribution and Processing
The fourth function is to protect the product during transit to the consumer. Packaging is part of the distribution process necessary to deliver goods to the consumer and facilitate handling and transportation. It also has affected international trade by making shipping of food products possible, allowing seasonal products to be more accessible out of season. Packaging can handle better when there are challenges in food distribution chain, such as heat, humidity, or dew. It is important to be aware of the distribution challenges and designing of package to suit it. In case of prepacked product, it should have the ability to stand the severity or type of process conditions, such as flexible packaging during canning, microwaveable foods, oven able, and reportable foods. Irradiated foods are usually prepacked prior to treatment by ionizing radiation, which prevents recontamination. Packaging materials are also exposed to radiation during treatment, though in this instance it can lead to radiation-induced degradation of the packaging material, followed by interaction between the material and food product.
Protective packaging is a term applied to packaging primarily designed to protect the goods, rather than for appearance or presentation, so it is generally used to apply to the outer containers used for transporting goods from the manufacturer to the point of sale, and filling materials inside the outer containers, e.g., nylon barrier-sealed bubble packaging (computer parts), urethane expanding foam, PE foam package “cushions,” and PS loose-fill packaging. The most widely used protective package is the outer carton. All packaging is protective as one of its primary functions, so it is more accurate to call this transport packaging or tertiary packaging (on the basis of the primary packaging in contact with the product, secondary for grouping units together for single purchase, and tertiary being for grouping secondary packaging for convenience distribution). A pallet is the frame base for carrying the transport packs. The primary packages are put into cartons and the sealed cartons are transported through specialized conveyors, allowing products from different processing lines and sorted onto individual product pallets. Another aspect of protective packaging involves primary packaging designed to prevent anyone from opening the package before purchase. Cases of extortion or sabotage are also reported. In the mid-1970s, child-resistant packaging became an issue, leading to the development of childproof lids for poisonous products. Tamper-resistant refers to the ability of the packaging to resist tampering (or opening), e.g., for child protection, whereas tamper-evident refers to the ability of the packaging to reveal that it has been opened.
16.3.5. Provide storage history
Time-temperature indicator (TTI) is effective for predicting microbial concentrations and other parameters of food quality during shipping and storage. It helps in ensuring proper handling and provides a gauge of product quality for sensitive products in which temperature control is imperative to efficacy and safety. TTIs are tags that can be applied to individual packages or shipping cartons to visually indicate whether a product has been exposed to time and temperature conditions that adversely affect the product quality. TTI could be used in chilled foods to identify the temperature abuse during storage and distribution. According to the response mechanisms, TTIs can be divided into three groups: (i) biological, (ii) chemical, and (iii) physical systems. One of them is the use of enzyme-based TTIs to monitor and predict shelf life of products. The tags are available in a one-dot version and a three-dot version with the three dots changing color at different rates. The change of color of the dot indicates the exposed time and temperature of the product. There is considerable potential for use of TTIs in the food distribution chain, but there are two issues to be considered. One is the economics. When using a TTI for a relatively low-cost product, such as lettuce, the indicator also has to be relatively low in cost. This should be considered or addressed by the manufacturer of the indicator. The other issue is knowledge of the food product. The food processor must know the degradation kinetics of his product—how the quality characteristics of his product are changing with time and temperature exposure—so that he can select the indicator that matches it.