How to eliminate the residual solvent and odor of plastic food packaging The development of plastic food packaging materials is intended to solve the problems of various types of foods that are susceptible to moisture, mildew, deterioration, etc. due to lack of packaging or packaging, but for some reasons, consumption often occurs. When opening the food packaging. The smell and even the smell in the bag are smelled, which leads to conflicts and disputes between many consumers and food factories, food factories and packaging plants, packaging plants and raw material suppliers. Hand Tool Set,Mechanic Tool Sets,Household Tool Kit,Household Hand Tool Sets SUZHOU NEWSTAR HARDWARE CO.,LTD. , https://www.hardwarenewstar.com
Production stage of packaging materials
In the production stage of packaging materials, printing, extrusion compounding, dry lamination and other processes will lead to the occurrence of "odor". The specific performance is as follows:
Residual solvent problem. A large amount of an organic solvent such as toluene, ethyl acetate, methyl ethyl ketone or the like is required in the gravure printing and solvent-type dry compounding processes of the plastic composite. According to the process requirements, these solvents should be volatilized during the production process. However, in actual production, there are always more or less solvents that are not completely volatilized for various reasons, so-called "residual solvents". "Residual solvent" is usually a mixture of several solvents. When the content of "residual solvent" is lower than a certain value, the human sense of smell does not feel its presence, and it does not affect the taste of the packaged food. When the content of "residual solvent" is higher than a certain value, the human sense of smell can be felt. When the consumer opens the food packaged with the packaging material with such high "residual solvent", it may smell Unlike the "odor" of the moldy and rotten taste of food.
The resin oxidizes the odor problem. Extrusion compounding is another compounding process for composite flexible packaging materials. In this process, it is necessary to melt the granular plastic resin at a high temperature and apply it to other substrates through a die and then to form it by cooling. If the temperature is too high, the plastic resin will oxidize and decompose, resulting in a so-called "resin oxidized odor". If the food is packaged with this material, the flavor of the food will change. This "odor" can be eliminated by strictly controlling the production process conditions.
Food packaging stage
Other flavors of the production hall will also be mixed into the packaging, especially for some air-packed foods such as potato chips and egg yolk pies. According to normal requirements, the air-filled food should be filled with pure nitrogen or a mixture of nitrogen and carbon dioxide. However, in order to reduce production costs, many companies are filled with ordinary air. In order to reduce the impact of the noise of the air compressor on the operator, the air compressor is often placed away from the packaging line, thus inevitably filling the tasteful air of other areas into the food bag. It is self-evident that the filling air is legal and not mentioned, and the oxygen in it will cause oxidation of certain components in the food.
Post-processing stage of food packaging
The process conditions such as temperature and time used for post-treatment do not meet the requirements, which may lead to the occurrence of "odor". In order to extend the shelf life of the food packaging, after the packaging process is completed, the packaged food is also sterilized, boiled at 100 ° C, cooked at 121 ° C, 135 ° C or 150 ° C, microwave sterilized, radiation radiation, and the like. The above sterilization methods all need to be maintained under a certain temperature or strength for a certain period of time to achieve the predetermined sterilization effect, and the sterilization conditions need to be adjusted according to the weight volume of the contents.
In the post-processing of food, the following problems are common:
High temperature cooking equipment does not meet the requirements. The high-temperature cooking and sterilizing equipment used in the composite flexible packaging bag is a special equipment, but many enterprises currently use the glass canned sterilization equipment or the ordinary pressure cooker for high-temperature cooking. As a result, the rate of breaking the bag is high, or the sterilization condition is relaxed in order to reduce the bag breaking rate, resulting in a shortened shelf life of the packaged food.
If you do not pay attention to the hygienic conditions of the early food processing, you will emphasize the post-sterilization conditions. On the one hand, it will lead to instability of product quality, on the other hand, it will increase the cost of packaging due to the requirement of packaging materials, and also bring inconvenience to consumers, such as cup jelly.
The shape of the contents cannot be standardized, and the individual differences are large, resulting in significant differences in the actual degree of sterilization in the same batch of products, such as food such as roast chicken.
Transportation and storage of packaged food
The transportation and storage conditions are relatively poor, and mechanical collisions are prone to occur between food packaging. The packaging bag is under excessive pressure. As a result, the packaging bag breaks the bag and loses its protective effect, causing the contents to be mildewed.
The temperature of transportation and storage is too high, which will cause the bacteria in the contents that are not strictly sterilized to multiply rapidly, and the food will deteriorate, resulting in a bag.
Poor selection of packaging materials, lack of gas, moisture, and shading, can not effectively protect the contents, will cause the contents to lose the original fragrance, moisture, discoloration.
Due to the poor packaging process, the sealing is not strict or the sealing is broken, so that the gas filled inside and the outside air and bacteria enter the inside of the packaging bag. Packaged foods are not sold or consumed in a timely manner, resulting in exceeding the shelf life.
The researchers found that the so-called "odor" of packaged foods has many forms of expression, and the causes of "odor" are also various, which may lead to "odor" in all aspects of food production, transportation, storage, sales and consumption. And ultimately the products produced can not achieve their value, resulting in the waste of social resources, or harm to the physical and mental health of consumers.
Therefore, the problem of “odor†of packaged food is not only a problem of food producers, but a problem that should be paid attention to in all relevant aspects of the whole society. It is a problem that should be paid attention to in all relevant aspects of production. Producers must have a sense of consumption. I want to think that “I am the consumer of my own products after I take off my work clothesâ€; consumers must have a sense of rights protection and care about their own health, especially not to buy cheap expired food. In addition, the relevant management departments should strengthen the management of related enterprises and eliminate the possibility of “exotic smell†of packaged foods from the source.
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