فصلنامه علوم و فنون بسته بندی
پیاپی 50 (تابستان 1401)

"Packaging design" is one of the main courses in the Iranian MSRT-authorized curriculum for the BFA major in visual communication. The present study aims to analyze the communication process of the packaging design course based on Jacobson's theory of communication and elaborate on some strategies to enhance communications and subsequently, increase effectiveness of the course. In the present study, the key research question is as follows: what actions can be taken to improve the current theory's six functions, and in general, to enhance the communication process in Iranian higher education's packaging design courses? The descriptive-analytical research method is applied, and the data collection is conducted through a combination of library research methods by note-taking and open-ended survey field interviews with the target population. The qualitative data analysis is used. The interviewees were selected in a targeted way, and the snowball (chain referral) method is applied. The results indicate that the actions to be taken in order to develop each of the six functions in Jacobson's theory and to meet the general needs of the course are as follows: (1) Implementing an interdisciplinary environment in the class and imitating real-world common collaborations in the industry; (2) Adopting diverse educational styles, presentations, and sources to achieve the course goals; (3) Careful consideration of four general rules, namely, collective brainstorming, engaging the industry as the course sponsor, directing students to attend end-of-semester design competitions, and highlighting various methods of communication between students and instructors; (4) Considering the principles and categories of the cognitive load theory; (5) Observing cultural requirements and using folk art models; (6) Applying hybrid physical/technological (online) learning as a robust educational strategy.

In this research work, the mechanical and thermal properties of reinforced films of starch, polylactic acid and cellulose nanofibers for use in the food packaging industry are investigated. Finding the effectiveness of each material by itself and their cumulative effects, studying the effects of starch, polylactic acid and cellulose nanofibers in making films and finding the appropriate portions of materials leading to the best achievable properties have been the objectives of this investigation. In this study, biodegradable nanocomposite films based on polylactic acid, starch and cellulose nanofibers as reinforcing agents were prepared using the solvent casting method. For the produced starch, nanofiber and cell films, the physical properties of thickness, color and structure were studied using the XRD and electron microscopy SEM scanning, whilst the WVP water vapor permeability and mechanical properties including tensile strength, Young modulus and tensile strength at break point, thermal properties including Tg, Tm and the crystallization percentage were investigated by the DSC and FTIR infrared spectroscopy. Scanning electron microscopy results showed the desirable uniform dispersion of starch, cellulose nanofibers with polylactic acid especially in starch and cellulose nanofibers on level (1) and polylactic acid with cellulose nanofibers on level (1.5). In the study of mechanical properties, the addition of cellulose nanofibers to starch films reduced the Young's modulus and increased the tensile strength at the rupture point. The tensile strength increased from 4.5 MPa to 6.63 MPa and 6.89 MPa for starch and cellulose nanofibers films. For polylactic acid and cellulose nanofibers films, the tensile strength increased from 8.76 MPa to 18.56 MPa and 22.69 MPa. For starch and cellulose nanofibers with polylactic acid, the tensile strength increased from 35.33 MPa to 36.99 MPa. It was also observed that the addition of cellulose nanofibers does not have considerable effects on water vapor permeability.

After harvesting, the ripening and spoilage of climacteric crops such as apples, bananas, kiwifruits, and tomatoes accelerate in the presence of ethylene. To increase the shelf life of these products, removing ethylene from their atmosphere is crucial. To achieve this aim, ethylene scavengers are utilized in free or encapsulated form, depending on their type, function, or specific purpose. The functions of the ethylene scavengers are different depending on their mechanisms, including oxidation, inhibition, and adsorption, which can be exemplified as potassium permanganate, 1-methyl cyclopropane, and zeolite respectively. In general, each encapsulation mechanism has its own function and characteristics. These methods include the stabilization of titanium dioxide particles on an inorganic and inert matrix such as borosilicate glass and quartz, the impregnation of potassium permanganate in a neutral matrix such as alumina, silica gel, and zeolite, photocatalytic coatings stabilization of titanium oxide in expanded polyethylene foam networks, and the use of gelatin and hydroxypropyl methylcellulose as hydrophobic and hydrophilic matrixes for the integration of titanium dioxide. In this study, different methods of ethylene scavenging and impregnation have been investigated.

Edible coatings refer to a thin layer of edible materials used on a product. Because conventional storage and packaging technologies require investment, the research activities over the past decade have become focused on the development of novel packaging systems such as food coatings. Hence, the present article describes the antimicrobial and antioxidant coatings, their effectiveness against microorganisms and their effects on the chemical quality of the product. This study investigates the data from some articles published by Science Direct, Pub Med, Escopus Springer Link, and Scopus databases on the edible coatings in Iran and other countries. The search was performed on the 2010 to 2022 publications and the following keywords were used: food coatings, seafood, oxidation, sodium alginate, whey protein, chitosan, gelatin, carrageenan, natural antioxidants, active packaging,       eco-friendly packaging, environmental pollution reduction, increasing shelf life, antibacterial compounds, food preservation, boosting quality characteristics and fresh fillet with no preservatives. The longest fillet shelf life was obtained from coatings containing 0.5% sodium alginate enriched with 0.5% ginger on Abramis brama (30 days), 2% fungal chitosan and enriched with 2%pomegranate peel extract (30 days) followed by 2% animal chitosan enriched with 0.25 carvacrol on Nile tilapia (21 days) refrigerated. The 3% gelatin on rainbow trout (3 days) and the 8% whey protein concentrate on Huso huso (4 days in refrigerator) had the lowest shelf life. The results of the present study showed that the carbohydrate-based coatings, such as chitosan and sodium alginate, compared to protein coatings such as whey protein, have greater ability to maintain the quality and freshness of fillets, and can reduce economic losses to a greater extent for the suppliers of fresh fillets. Also, compared to non-enriched coatings, the enriched ones are more capable of increasing the quality characteristics and shelf life of fresh fish fillets.

Packaging is involved in achieving safety goals and preventing food waste. Due to the increasing bio environmental warnings, today the focus is on the search for biodegradable and environmentally friendly food films under the title of food films and coatings.  As edible coatings and films are natural, environmentally friendly and degradable products, they can be good alternative for the synthetic packaging. In addition, the main advantage of these packages is their use as carriers of food additives such as flavorings, antimicrobials, antioxidants, enzymes and dyes.  Also, due to their preventive and inhibitory properties, food coatings and films reduce or inhibit the growth of microorganisms and therefore can maintain the quality of food and thus increase the shelf life of the product. Food processing has become a serious risk and challenge for the environment due to the poor management of waste from lateral flows and due to the non-utilization of waste. The by-products have not yet received enough attention because of their richness in some valuable compounds. This review paper has investigated the edible films and coatings produced from some wastes of the fruits' peels and plants, and their characteristics.

Ordinary plastics have been produced and used for many years for packaging applications in various sectors. With the growth of the food industry, the demand for food packaging has also grown. However, the plastics made from petroleum are non-degradable, which has created severe bio environmental problems for the environment. Biodegradable polymers are an alternative approach to many industrial applications including food packaging, as well as risk control for non-biodegradable plastics. According to the type of the raw material, they are classified in one of the following categories: polymers extracted from biomass compounds, polymers synthesized from monomers and polymers produced from microorganisms. The quality of biopolymers depends on their physical, mechanical and thermal properties. The present study is an overview of the properties of different biopolymers and their compounds, comparing the properties of biodegradable polymers and biopolymers. The recent research works and innovative methods for the use of these plastics for food packaging and biomass plastic poisoning have also been studied and presented, concluding that biodegradable polymers help reduce the environmental impacts of plastics. It is worth mentioning that as the plastics from agricultural waste are used as raw materials for making this kind of packaging, there is a great opportunity to increase added value.