High temperature resistant retort bags have the properties of long-lasting packaging, stable storage, anti-bacteria, high-temperature sterilization treatment, etc., and are good packaging composite materials. So, what matters should be paid attention to in terms of structure, material selection, and craftsmanship? Professional flexible packaging manufacturer PACK MIC will tell you.
Structure and material selection of high temperature resistant retort bag
In order to meet the performance requirements of high-temperature resistant retort bags, the outer layer of the structure is made of high-strength polyester film, the middle layer is made of aluminum foil with light-shielding and airtight properties, and the inner layer is made of polypropylene film. The three-layer structure includes PET/AL/CPP and PPET/PA/CPP, and the four-layer structure includes PET/AL/PA/CPP. The performance characteristics of different types of films are as follows:
1. Mylar film
Polyester film has high mechanical strength, heat resistance, cold resistance, oil resistance, chemical resistance, gas barrier and other properties. Its thickness is 12um /12microns and can be used.
2. Aluminum foil
Aluminum foil has excellent gas barrier and moisture resistance, so it is very important to preserve the original taste of food. Strong protection, making the package less susceptible to bacteria and mold; stable shape at high and low temperatures; good shading performance, strong reflection ability to heat and light. It can be used with a thickness of 7 μm, with as few pinholes as possible, and as small a hole as possible. In addition, its flatness must be good, and the surface must be free of oil spots. Generally, domestic aluminum foils cannot meet the requirements. Many manufacturers choose Korean and Japanese aluminum foils product.
3. Nylon
Nylon not only has good barrier properties, but also is odorless, tasteless, non-toxic, and is particularly puncture resistant. It has a weakness that it is not resistant to moisture, so it should be stored in a dry environment. Once it absorbs water, its various performance indicators will decline. The thickness of nylon is 15um(15microns) It can be used immediately. When laminating, it is best to use a double-sided treated film. If it is not a double-sided treated film, its untreated side should be laminated with aluminum foil to ensure the composite fastness.
4.Polypropylene
Polypropylene film, the inner layer material of high temperature resistant retort bags, not only requires good flatness, but also has strict requirements on its tensile strength, heat sealing strength, impact strength and elongation at break. Only a few domestic products can meet the requirements. It is used, but the effect is not as good as imported raw materials, its thickness is 60-90microns, and the surface treatment value is above 40dyn.
In order to better ensure food safety in high-temperature retort bags, PACK MIC packaging introduces 5 packaging inspection methods for you here:
1. Packaging bag airtightness test
By using compressed air blowing and underwater extrusion to test the sealing performance of materials, the sealing performance of packaging bags can be effectively compared and evaluated through testing, which provides a basis for determining relevant production technical indicators.
2. Packaging bag pressure resistance, drop resistance performance test.
By testing the pressure resistance and drop resistance performance of the high temperature resistant retort bag, the rupture resistance performance and ratio during the turnover process can be controlled. Due to the ever-changing situation in the turnover process, the pressure test for a single package and the drop test for the whole box of products are carried out, and multiple tests are carried out in different directions, in order to comprehensively analyze the pressure and drop performance of the packaged products and solve the problem of product failure. Problems caused by damaged packaging during transportation or transit.
3. Mechanical strength test of high temperature retort bags
The mechanical strength of the packaging material includes the composite peeling strength of the material, the sealing heat sealing strength, the tensile strength, etc. If the detection index cannot meet the standard, it is easy to break or break during the packaging and transportation process. The universal tensile tester can be used according to the relevant national and industry standards. and standard methods to detect and determine whether it is qualified or not.
4. Barrier performance test
High-temperature resistant retort bags are generally packed with highly nutritious contents such as meat products, which are easily oxidized and deteriorated. Even within the shelf life, their taste will vary with different dates. For quality, barrier materials must be used, and therefore strict oxygen and moisture permeability tests must be carried out on the packaging materials.
5. Residual solvent detection
Since printing and compounding are two very important processes in the high-temperature cooking production process, the use of solvent is necessary in the process of printing and compounding. The solvent is a polymer chemical with a certain pungent smell and is harmful to the human body. Materials, foreign laws and regulations have very strict control indicators for some of the solvents such as toluene butanone, so solvent residues must be detected during the production process of printing semi-finished products, composite semi-finished products and finished products to ensure that the products are healthy and safe.
Post time: Aug-02-2023
