Analysis of Key Points of Zongzi Packaging Inspection

[China Packaging News] The quality of the packaging performance is an important factor that affects whether the dumplings can be kept intact during storage. The soft plastic composite film packaging of the dumplings is generally divided into two types: inner packaging and outer packaging. This article analyzes the two The main points of packaging performance detection, and introduces the test method of each performance, provides a reference for the enterprise to monitor the quality of the soft plastic composite film material of the packaging dumplings.

1. Meaning

Zongzi is a traditional festival food in China. With the extension of storage time, its packaging form has gradually evolved from the traditional single zongye packaging to the dual packaging form of zongye plus soft plastic composite film. Common soft plastic composite film materials for packaging dumplings are mostly plastic composite films. These plastic composite films can be divided into inner packaging and outer packaging according to whether they are in direct contact with the dumplings. The role of each packaging is different, and the inner packaging focuses on In order to protect the components of the rice dumplings and prevent the rice dumplings from deteriorating, the outer packaging focuses on the protection of the integrity of the packaging and prevents the bags from being broken, so the focus on the performance of the inner and outer packaging should be different. This article analyzes the key points of the inner and outer packaging of zongzi packaging.

2. Barrier performance

There are many varieties of rice dumplings, such as meat dumplings, bean dumplings, jujube rice dumplings, ham rice dumplings, babao rice dumplings, egg yolk rice dumplings, etc. The composition of the rice dumplings determines their characteristics of being easily oxidized and deteriorated, and easy to mold. It is the basic requirement for dumplings packaging. From the completion of packaging to the consumption process, the inner packaging should always ensure that the dumplings are in a closed environment, so the composite film material used in the inner packaging will have better oxygen barrier properties and will have a better quality preservation effect on the dumplings. The oxygen barrier properties of flexible plastic packaging materials are characterized by oxygen transmission rate. The test methods are mainly divided into two types: differential pressure method and isobaric method. The test standards are based on GB / T 1038-2000 "gas permeability of plastic film and sheet" Test Method of Differential Pressure, GB / T 19789-2005 "Coulometer Test Method for Oxygen Permeability Test of Plastic Films and Sheets of Packaging Materials".

3. Physical and mechanical properties

The good physical and mechanical properties of flexible plastic packaging materials can make it cooperate well with the packaging equipment, successfully complete the packaging process, and ensure that the dumpling bags are not broken, leaked, layered, and have a good appearance during storage and sales.

3.1 Flexibility

The inner packaging of dumplings generally adopts vacuum packaging. Good flexibility can make the packaging material fit well on the surface of the dumplings, which is easy to remove the air in the packaging bag ; the good flexibility of the outer packaging bag can make the packaging bag in No bag breakage occurs when dropped or impacted by foreign objects. The flexibility of flexible plastic packaging materials can be expressed by tensile properties and impact resistance. The test method can refer to the standard GB / T 1040.3-2006 "Determination of plastic tensile properties Part 3 : Test conditions for thin plastics and sheets", GB / T 8809-2015 "Test Method for Plastic Film Resistance to Pendulum Impact".

3.2 Anti-puncture performance

The bumps formed on the inner packaging surface of the dumplings are generally harder and will have a greater puncture force on the contacting packaging materials. Therefore, the inner packaging and the outer packaging should have strong puncture resistance to ensure that the packaging bag will not be damaged. The sharp puncture breaks the bag. The testing process of the puncture resistance of packaging materials can be based on the standard GB / T 10004-2008 "Plastic composite film for packaging, dry compounding of bags, extrusion compounding". The equipment used is an intelligent electronic tensile testing machine.

3.3 Heat seal strength

The heat seal strength is a performance index that characterizes the sealing fastness of the heat seal of the packaging bag. If the heat seal strength of the packaging bag is poor, and the phenomenon of poor sealing or excessive heat sealing occurs, it will occur slowly during the storage and sale of dumplings Air leakage, problems such as bag swell, mold, and deterioration, or broken bags at the seal when they are dropped or impacted by foreign objects. Whether the heat sealing strength of the dumpling packaging bag is good is related to the heat sealing layer, heat sealing temperature, pressure and time of the inner packaging and outer packaging materials. The test method for the heat sealing strength of the packaging bag is QB / T 2358-1998 " Testing method for the heat sealing strength of plastic film packaging bag", and the testing equipment is an intelligent electronic tensile testing machine .

3.4 High temperature resistance

Zongzi is generally sterilized by high-temperature sterilization, which requires that the composition material and adhesive of the soft plastic composite film used in the inner packaging should have good high-temperature resistance to prevent the packaging bag from breaking after high-temperature heating. Air leakage, delamination, shrinkage and other phenomena. The high temperature resistance of the packaging material can be obtained by simulating the sterilization conditions of the dumplings, observing the surface state of the packaging bag after high temperature treatment and testing the sealing performance. The testing equipment used in the test includes a high pressure cooking pot and a sealing tester.

3.5 Low temperature resistance

Some dumplings need to be stored at low temperature. In order to prevent the performance of the inner packaging bag and the outer packaging bag from deteriorating under low temperature conditions and prone to broken bags and air leakage, the soft plastic composite film material used should have good low temperature resistance. . The test of low temperature resistance of packaging materials can refer to the standard QB / T 1871-1993 "Bidirectional Stretch Nylon (BOPA) , Low Density Polyethylene (LDPE) Composite Film, Bag" method requirements, the test equipment is the film impact test instrument.

4. Hygienic performance index

The hygienic performance indexes of the soft plastic composite film material for packaging dumplings are mainly the residual solvent, total migration, heavy metal, potassium permanganate consumption, toluene diamine in the inner packaging materials that can migrate into the dumplings, and the inner packaging and dumplings During the exposure process, these harmful substances will gradually migrate into the dumplings and affect the health of consumers. Therefore, the content of harmful substances that can be migrated in the inner packaging should be controlled as much as possible. The test process of solvent residues can refer to the standard GB / T 10004-2008 "Plastic composite film for packaging, dry compounding of bags, extrusion compounding", and the remaining indicators are based on the standard GB 31604.8-2016 "National Food Safety Standard Food Contact Materials" Determination of total migration of products and products ", GB 31604.9-2016 " Determination of heavy metals in food contact materials and products of food safety standards ", GB 31604.2-2016 " National food safety standards of food contact materials and products potassium permanganate "Determination of consumption", GB 31604.23-2016 " Determination of diaminotoluene in food contact materials and products composite food contact materials of national food safety standards".

5. Conclusion

Choosing packaging materials with good compatibility with dumplings and monitoring the performance of the materials in a timely manner are effective measures to prevent problems such as bag breakage and deterioration caused by packaging problems. The key monitoring indicators of the inner packaging materials used for packing dumplings include oxygen permeability, tensile properties, impact resistance, puncture resistance, heat seal strength, high temperature resistance, cold resistance, solvent residue, total migration, heavy metals, high Potassium manganate consumption, toluene diamine, etc., the key performance of outer packaging materials include tensile properties, impact resistance, puncture resistance, heat seal strength, cold resistance, etc.