[LLDPE] Vacuum Bags, the Key Element of Sous Vide Cooking

“Sous-vide” is a popular example of cooking meets science. When food, usually meat, is sealed inside a plastic bag and cooked slowly in a water bath at a steady temperature, it comes out perfectly tender and juicy. The key element of mastering the art of sous vide is the vacuum pack, which needs to transfer heat from water but prevent any moisture from seeping into the packaging.

LG Chem’s Linear Low-Density Polyethylene (LLDPE) is the material used to make these vacuum packs, multi-layered and laminated with nylon. Since LLDPE is a high-performance material with a higher strength than LDPE (Low-Density Polyethylene), it does not tear easily and is resistant to heat.

LLDPE can be applied to a wide range of film and packaging products in food, agriculture, and industries through various processing methods. The most common processing methods are blown and cast film extrusions. In the blown film extrusion, LLDPE grains are melted and extruded into a tube, then blown to generate bubbles. By controlling the amount of air, this process can produce wide-width films for greenhouses and film sheets. The excellent strength of LLDPE is also great for food wraps and heavy-duty shipping sacks. On the other hand, the cast extrusion method compresses the product and cools it on a metal roll. Because the film cools quickly and has good transparency, it is used to make food wraps and stretch film for logistics packaging.

LG Chem’s technology is part of these diverse applications of LLDPE in everyday life.