Common Food Packaging Materials
Paper, plastic, metal and glass are commonly used food packaging materials.
Paper packaging material has many advantages: low price, economy, good protection performance, good flexibility in production, convenient storage and transportation, easy to shape and decorate, no pollution to the interior, can be synthesized with other materials and improve material performance, so it is widely used as a packaging material. At the same time, because paper packaging can be recycled after use, even if a small amount of paper is abandoned in the environment, it can be decomposed naturally, which has no adverse impact on the natural environment, so paperboard and its products are green products, which meet the requirements of environmental protection, and can be used to replace some plastic packaging materials to reduce the plastic caused. White pollution can play a positive role. With the enhancement of people's awareness of environmental protection and the actual needs of life, the development of vegetable fiber fast food boxes and natural green packaging materials will be the trend of paper products and food packaging materials in the future. In addition, with the rapid development of packaging technology, edible packaging paper is an important development direction of modern food packaging. This kind of packaging has important environmental protection and economic value. At present, there are two kinds of edible paper abroad. One is to use vegetables as the main raw material to form and dry the vegetables. The other is to paste starch and sugar and add other food additives to form the edible paper in a similar way. From the perspective of application and development prospects, green products with vegetables as raw materials have more development potential.
Polymer plastics have become an important food packaging material. It is widely used because of its light weight, easy use, barrier, permeability, heat resistance, cold resistance, good corrosion resistance, and colorful appearance. Because plastic materials and plastic-containing composite materials have advantages that other materials do not have, plastic products and composite packaging materials play an important role in food packaging materials. Therefore, it has developed rapidly in recent decades, and it is estimated that the plastic packaging market will have a great growth in the future. Moreover, its own substances are not easy to move into packaged food, but some free monomers and crackers which are not involved in the polymerization, as well as stabilizing, plasticizing, lubricating and coloring agents added for the appearance durability of packaging materials, will also produce toxic effects if the quality is not appropriate, which will lead to its unsafe. It is noteworthy that polymer packaging materials have a prominent shortcoming, which is not easy to degrade, and incineration will produce toxic gases. And plastic packaging materials belong to the shortest use cycle of plastic products, generally for one month to three months, the longest one year. Since then, most of them have become municipal solid waste into the garbage treatment system, and some are discarded at will, resulting in "white pollution". Plastic packaging materials account for the largest proportion of waste, and their pollution to the environment is also the most serious among all kinds of packaging materials. The current treatment scheme is to combine recycling with the development and application of degradable plastics. In addition, due to the defects of plastic products, their moisture resistance and barrier are generally worse than metal and glass containers, so it is very important to improve the performance of existing plastics, develop new varieties, improve strength and barrier, reduce dosage, reuse, classification and recycling.
Metal materials have high mechanical strength, firm, pressure-resistant, non-fragmentation, ductile, bitable, weldable, bondable, excellent moisture resistance and air tightness, as well as easy recovery and treatment. Their waste pollution to the environment is relatively small compared with plastics and paper, so metal occupies a phase in packaging materials. When important. Canned food and some liquid, paste, powder or high-grade food are often packaged with this kind of material. The commonly used metal packaging materials are tinplate and aluminium, which are widely used in the manufacture of food and beverage packaging cans. Because metal packaging materials are easy to recycle and dispose, the environmental pollution caused by their waste is less than that of plastics and paper. The commonly used metal packaging materials are tinplate and aluminium, which are widely used in the manufacture of food and beverage packaging cans. In recent years, the change and development direction of metal cans are: (1) increasing the strength of materials and reducing the thickness of substrates can greatly save the consumption of metal materials, reduce costs, and reduce the environmental impact of non-recycled cans; (2) reducing the tin plating amount of tinplate; (3) replacing aluminum cans with tinplate, because of aluminium. Because of its high cost and unstable value, many countries use tinplate instead of aluminium to produce two pieces of cans for food and beverage; (4) resistance welding is used to realize lead-free pollution; (5) aluminum foil is used instead of plastic and paper because the recovery of aluminium foil is very easy and there is little pollution to the environment, so it is better to use aluminium foil instead of plastic and paper. Better development direction. Many foods can be packaged in containers made of aluminum foil.
