Regulatory agencies that monitor food and beverage production require the use of food-grade materials at any point that the material may contact food. Packaging is no exception to these rules, leading to the development of food-safe plastics for use in packaging consumable products. Food-grade plastics follow stringent, government-monitored manufacturing processes to ensure they are safe for food contact.
Numerous plastics are approved for food contact, leading to their use as food packaging. This article will discuss the types of food-grade plastics used in the packaging sector.
Polyethylene Terephthalate (PET)
PET is relatively ubiquitous, used in soft drink and single-use water bottles, as well as food-grade containers, bakery trays, snack packs, produce containers, and more. PET resin won’t degrade upon food contact, which makes it a popular choice for food packaging. Some of the other beneficial properties of PET include lightweight, high impact resistance, and corrosion resistance.
Crystallizable Polyethylene Terephthalate (CPET)
CPET has undergone a process to make it more resistant to cracking when it experiences impacts at low temperatures, which is a common drawback of some standard PET plastic containers. CPET is more flexible and can withstand higher temperatures, making it appropriate for producing plastic food trays used with conventional oven, microwavable dinners, oven-proof plastic wrap, microwaveable storage containers, and more. CPET is also commonly used for ready-to-eat meals as well.
Polypropylene is an ideal food-safe plastic for production processes that require high heat. It can be found in products ranging from prescription bottles to garden tools and automotive products. While fairly stiff, polypropylene is not as brittle as other common food packaging plastics. Food items that utilize polypropylene for packaging include yogurt, cream cheese/sour cream containers, ready-to-eat meals and VSP containers. Polypropylene has gained popularity for microwavable containers thanks to its high melting point.
There are many types of plastic films with vastly different qualities based upon the material from which they are made. Some of the most common structures include lidding film, shrink wrap, VSP film, stand-up pouches, and specialty bags. In general, plastic film has many benefits. It is typically lightweight and resistant to contamination. Most plastic films can be printed on, helping to improve brand recognition and aesthetics. Here are some of the most common plastics used to make plastic films:
Low-density polyethylene (LDPE)
LDPE is the most inexpensive material for plastic films. It is flexible, soft, transparent, glossy, and features high resistances to moisture, tearing, and chemicals. It is most commonly found in plastic bags but is also widely used for squeezable food bottles, bread and frozen food packaging, and flexible lids.
Linear Low-Density Polyethylene (LLDPE)
LLDPE is similar to LDPE, but it features higher tensile and impact strengths and improved heat-sealing qualities. LLDPE the highest flexibility of the polyethylene sheeting varieties. In the food and beverage industries, it is largely used in bottle caps and shrink wraps.
Ultra Low-Density Polyethylene (ULDPE)
ULDPE is a soft thermoplastic that has superior low-temperature flexibility and flex crack resistance. ULDPE has high optical clarity and is tear-resistant. It is used for cheese, meat, and coffee packaging.
Medium-density polyethylene (MDPE)
MDPE is not as commonly used as the other forms of polyethylene flexible plastic sheeting. However, it is stronger and more resistant to tears, punctures, and chemicals than LDPE and is oxygen permeable. MDPE is used for packaging baked goods, heavy-duty produce bags, wash bottles, and dispensing bottles.
High-density polyethylene (HDPE)
HDPE is the most widely used polyethylene film for food packaging. It is semi-translucent and highly solvent-resistant. HDPE is the least flexible and strongest of the polyethylene films, making it perfect for applications where it needs to hold its shape. HDPE is found in bottles for storing water, juice, or milk; margarine and butter tubs; cereal box liners; and retail and grocery bags.
Most PP is not transparent like PET, but translucent, letting in light, but not being able to clearly see through it. Polypropylene has high optical clarity high gloss, good tensile strength, and low cost. It also possesses good barrier properties and a high melting point, making it ideal for items that need high temperature sterilization, such as baby bottles. It is commonly used for salad dressing bottles, yogurt containers, margarine tubs, and microwavable kitchenware.
PC is a long-lasting, transparent, heat-resistant, and robust thermoplastic. It has superior impact resistance and optical clarity. PC is used for sterile medical packaging and to protect contents from scratches, chemicals, and weathering. It is also used in commercial reusable water bottles and sterilizable baby bottles.
Polyvinyl Chloride (PVC)
PVC is an inexpensive and highly versatile thermoplastic. It can be formulated as rigid or flexible, has high impact strength, good dimensional stability, is oxygen permeable, and operates as a barrier to oil and grease. PVC is used in tubing for food and beverage applications, as well as blister packaging for breath mints or gum.
Polyethylene Terephthalate (PET)
PET is a high-performance, clear thermoplastic useful for making films. PET film features high tensile strength, low moisture absorption, and excellent dimensional stability throughout a wide range of temperatures. It is used for plastic bottles for carbonated drinks, bags, snack food wrappers, bottles, jars, and tubs. Biaxially-oriented polyethylene terephthalate (BOPET) is a related material made from stretched PET to create polyester film. BOPET is commonly used as faux-foil packaging and protective film on microwavable meals.
Polyvinylidene Chloride (PVDC)
PVDC is a synthetic thermoplastic that creates an outstanding oxygen and moisture barrier. It also resists heat, chemicals, oil, and grease. It is used most often in food and medicine packaging to extend shelf life.
Most commonly known by the popular name nylon, polyamide is strong, has a high melting point, creates a good oxygen barrier, and does not dissolve or absorb grease, oil, or acidic foods. The material also features good scratch, puncture, and flex-crack resistances. This material is used in microwave and conventional cooking applications.
Plastic Food Packaging from Point Five Packaging
As an industry leader in food packaging, Point Five Packaging offers an expansive portfolio of food-safe plastic packaging for use with virtually any type of food or beverage product. We pride ourselves on our extensive network of suppliers and our advanced packaging equipment portfolio. We employ a variety of veterans to the food industry who can suggest design optimizations and help our customers identify the optimal material for their needs.