Packaging materials are an important factor that affects the quality and shelf life of meat products, as well as their distribution channels and sales radius. The packaging of most raw and processed meats is susceptible to contamination from light, moisture, oxygen, and microorganisms during storage and transportation, which can shorten their shelf life and even cause food safety issues. Therefore, maintaining the good quality of meat products, preventing them from spoiling and deteriorating, and creating a more convenient consumption pattern are major challenges faced by meat production enterprises. The emergence of high barrier packaging materials has effectively addressed these issues. With the development of technology, high barrier packaging materials have become widely used in the meat industry, making significant contributions to ensuring the quality of meat products and promoting their development.
1. What is high barrier plastic packaging material?
High barrier plastic packaging material is a type of plastic packaging material that effectively isolates external factors such as air, moisture, light, and odor. It can protect the freshness, nutritional value, and taste of the packaged items to a certain extent and extend their shelf life. High barrier plastic packaging materials are usually composed of various composite materials, such as polyethylene, polyester, polyamide, and aluminum foil. These materials are layered to form a plastic film with high barrier properties, which can be applied to packaging in various fields, including food, medicine, cosmetics, electronics, and industrial products.
2. Application of high barrier packaging in meat products
Packaging fresh and cooked meat products with high barrier packaging materials combined with vacuum or modified atmosphere packaging such as shrink bag can extend the shelf life of products and ensure their quality by combining with sterilization technology. The main indicators for evaluating the effect of high barrier packaging materials on meat products are microbial spoilage and oxidative deterioration of meat products.
2.1 Effectively slowing down meat oxidation
Studies have found that under the same light-avoiding storage conditions, the fresh duck breast meat vacuum packed in PVC packaging bags has a higher TBA value than the product vacuum packed with high barrier packaging. This may be because the oxygen content in the PVC treatment group is higher, and the PVC packaging has lower oxygen barrier properties. Therefore, using high barrier packaging bags to vacuum pack duck meat can effectively slow down fat oxidation.
Research has also found that after 5 days of storage at 0℃~5℃, the degree of oxidation (POV value) of vacuum-packed beef sauce is significantly lower than that of products packaged with a freshness film (P<0.05). In cured meat products, due to the poor blocking properties of ordinary packaging materials, the POV value is higher compared to high barrier packaging. As a control, the high barrier packaging bag selected has high barrier properties and has a small change in POV value.
Studies have found that high barrier Shrink Film containing PVDC can effectively reduce the degree of protein oxidation in meat products and achieve better storage effects. In addition, research has found that PVDC materials with higher barrier properties can effectively suppress the "off-flavor" caused by two types of oxidation compared to PET/PA/CPP materials after storing roast chicken for 6 months.
2.2 Barrier to moisture and oxygen, inhibiting microbial growth
Some scholars have used composite packaging materials mainly composed of high barrier EVOH and four other materials, PET/PA/CPP, PA/modified PE, PA/CPP, and PE/PA/EVOH/PA/LLDPE, to package Taiwan sausages. It was found that EVOH Shrink Bags have significant advantages in reducing total bacterial count and the product has a longer shelf life.
Using high barrier materials containing PVDC, medium barrier materials containing PET, and low barrier materials to package fresh beef, it was found that the total bacterial count of the low barrier group was significantly higher than that of the medium and high barrier groups. The use of medium and high barrier materials extended the shelf life by 14 days compared to the low barrier group. When comparing a high barrier nylon and polyethylene composite steaming bag with a regular polyethylene sterile bag and a thin film preservation bag for fresh chicken breast, it was found that the total bacterial count in the steaming bag was significantly lower than that in other packaging methods (P<0.05). High barrier plastic materials can prolong the storage time of meat products, but they should be combined with the correct packaging methods to be effective. A higher barrier material does not necessarily mean better barrier performance; while a higher barrier material allows less oxygen to enter the package, it may also lead to the growth of anaerobic microorganisms, causing meat products to spoil.
Most safety assessments indicate that harmful substances, such as plasticizers, inks, and vinyl, may migrate from packaging materials used for fresh and processed meat products, but typically do not exceed the prescribed limits. Therefore, future developments in packaging materials should focus on the materials themselves, researching safer materials for food packaging to avoid harmful substances affecting people's safety due to migration, and addressing the degradation and disposal of materials to prevent pollution.
