فصلنامه علوم و فنون بسته بندی
پیاپی 54 (تابستان 1402)

This research was conducted with the aim of investigating the effect of using biodegradable nanostructure coatings on water absorption and other physical and mechanical properties of white paper used in cold environments. For this purpose, 127 g/m2 white paper was prepared and tested. First, the liners were mounted on a plywood. After applying the coating and preparing several samples, papers with the same coating weight were selected for testing. Due to the impossibility of exact coverage amount, liners with a coverage of about 15 g/m2 were used for the next tests. After the application, the coated papers were dried at room temperature. Then the samples were placed in the refrigerator for 2 and 4 months. Before the test, the control and coated samples were placed in standard environmental conditions (temperature 20 οC and relative humidity 65%). The results showed that the water absorption of the samples decreased after coating. The reason for this is that the coating solution used has penetrated the pores of the paper and caused the diameter of the pores to decrease, as a result, the speed of water passing through the pores of the paper has decreased. In coated and frozen samples, an increase in thickness and a decrease in surface smoothness and resistance properties have been observed compared to unfrozen control samples.

Using of chitosan biopolymer has been developed in the form of edible film and coating as a packaging material for food products. The physical and mechanical properties of chitosan film are influenced by various factors. To investigate the impact of effective factors on the film-forming solution, the present experiment in a completely randomized design using the 23 factorial method, a total of 8 treatments including the level (2 and 4%), molecular weight (high and low) of chitosan and solvent type (acetic acid and citric acid) used in film preparation was carried out. The physical and mechanical parameters of the films were measured. Also, the microstructure of the films was investigated using scanning electron microscope (SEM) images and infrared spectroscopy (FTIR) spectra. The results showed that 4% high and low molecular weights chitosan films which were dissolved in the acetic acid had the highest tensile strength (0.16 ± 0.01 MPa), Young's modulus (2.45 ± 0.55 MPa) and impermeability (2.17 ± 0.09 ± 0.09 g/msPa), and the highest elongation at break (54.33% ± 0.95%) was observed in 4% high molecular weight chitosan film with citric acid solvent (p<0.05). In addition, high molecular weight chitosan film dissolved in acetic acid was more transparent compared to citric acid (p<0.05). SEM images and IR spectra analysis confirmed the obtained results. Therefore, the physical and mechanical performance of the chitosan film was affected by the level and molecular weight of chitosan, and especially the type of acidic solvent, as well as the interaction effects of these factors. In general, the use of a higher level and molecular weight of chitosan leads to the production of a better film, and acetic acid is a more suitable solvent than citric acid.

The purpose of this research was to identify and prioritize the barriers to using blockchain technology in the supply chain of food packaging companies in Shahrekord. This is an applied research that is mixed (qualitative and quantitative). The statistical population of the research is the experts of Shahrekord food industry packaging companies, using the purposeful sampling method and the use of theoretical saturation, the number of 10 experts was selected as a sample. In this regard, by using field and library studies and the method of content analysis, the obstacles to the use of blockchain in the sustainable supply chain were identified and ranked using the Dimetal technique. The results showed that the lack of management commitment is the most influential factor on other factors, and the rest of the factors are internal obstacles, lack of familiarity of employees, lack of specific rules, sustainability obstacles, obstacles outside the organization and infrastructural obstacles. It shows the effect of other factors on this factor.

The purpose of this research was to investigate the effect of progressive human resource management on theThe purpose of this research was to identify and prioritize the barriers to using blockchain technology in the supply chain of food packaging companies in Shahrekord. This is an applied research that is mixed (qualitative and quantitative). The statistical population of the research is the experts of Shahrekord food industry packaging companies, using the purposeful sampling method and the use of theoretical saturation, the number of 10 experts was selected as a sample. In this regard, by using field and library studies and the method of content analysis, the obstacles to the use of blockchain in the sustainable supply chain were identified and ranked using the Dimetal technique. The results showed that the lack of management commitment is the most influential factor on other factors, and the rest of the factors are internal obstacles, lack of familiarity of employees, lack of specific rules, sustainability obstacles, obstacles outside the organization and infrastructural obstacles. It shows the effect of other factors on this factor.

The packaging film consists of very thin plastic whose main component is plastic and elastomeric materials. In general, films are used to protect goods from damaging factors. Almost any plastic can be made into film, but this study will only discuss those that are used for commercial packaging. In this research, the types of common polymers used for flexible packaging programs in all industries and the strategy of polymer selection for the production of suitable films are studied, and the role of flexible packaging films in the material supply chain. Food and the role of flexible packaging films in medical equipment and the types of materials used in multi-layer flexible packaging are discussed. Also, thermal properties and polymer seals are studied and application programs are presented for flexible packaging film structures, biaxial and multiaxial films. And finally, a look at the technology of multilayer flexible film structures and a list of polymers used to produce normal buffer layers, bulky layers, interface layers or sealants for layered structures for various applications is described.

The presence of excessive quantities of compounds such as oxygen, moisture, ethylene and carbon dioxide in the packaging of food products results in their vulnerability and spoilage. The rise of many new food products in the markets as well as consumer demands to constantly monitor the quality of goods until consumption, in addition to the necessity for lowering food corruption during preservation time, have led to the development of some modern packaging technologies, such as active packaging. In this review, an overview of the techniques used in active packaging, including oxygen, ethylene, moisture, carbon dioxide, unpleasant flavors and odor scavengers, is provided. Oxygen scavengers, by removing this gas from the packaging environment, prevent the growth of aerobic microorganisms, spoilage and minimize the quality changes of sensitive foods to oxygen. In order to remove ethylene from the headspace of climacteric products and as a result, reduce the rate of deterioration and increase their shelf life, this gas scavenger is used. The main purpose of using the moisture scavengers is to reduce the quantity of water activity of the product, which in turn inhibits microbial growth, and maintains the desired texture and nutrients. Carbon dioxide scavenging systems, by removing excess amounts of this gas, prevent the increase in pressure or volume of packages containing fermented and roasted food products, and flavor and odor scavengers improve the quality and desirability of food products. Also, in this study, the conventional methods used to remove compounds in packaging, the mechanism of action, as well as the advantages of active scavenging systems and their effect on maintaining the quality and shelf life of packaged food are investigated.