Plastic containers are made from different polymers, the combination of which results in a product that is or is not of food grade quality, as defined by the U.S. Food & Drug Administration (FDA). All plastic containers used to store food must be of food grade quality (pharmaceuticals are stored in containers with even higher requirements), and may not have any dyes or recycled plastics that have been determined to be harmful to humans. The type of plastic must also be suitable for the application since foods that are highly acidic, or that contain alcohol or fats, can leach plastic additives from the packaging or container into the food. Finally, any plastic container that is made of food grade plastic but has been used to store non-food items, in particular chemicals or detergents, is no longer considered food grade.
Note that not all HDPE plastic is of food grade quality. Check that it is marked “Food Grade” before purchasing it. If you cannot confirm that the plastic used is food grade, then assume it is not and look for something else.
Other types of plastic containers to avoid:
Laundry detergent or kitty litter buckets
Dry pet food buckets
Household storage containers
In the United States, the following codes, known as the Resin Identification Codes, are stamped on all containers used for food. They identify the seven categories of plastic used in nearly all plastic containers and product packaging:
PET or PETE (polyethylene terephthalate) is a clear, tough polymer with exceptional gas and moisture barrier properties. PET’s ability to contain carbon dioxide (carbonation) makes it ideal for use in soft drink bottles.Examples: Soft drink bottles, detergent bottles
HDPE (high density polyethylene) is used in milk, juice and water containers in order to take advantage of its excellent protective barrier properties. Its chemical resistance properties also make it well suited for items such as containers for household chemicals and detergents. Most five gallon food buckets are made from HDPE.Examples: Milk bottles, shopping bags
Vinyl (polyvinyl chloride, or PVC) provides excellent clarity, puncture resistance and cling. As a film, vinyl can breathe just the right amount, making it ideal for packaging fresh meats that require oxygen to ensure a bright red surface while maintaining an acceptable shelf life.Examples: Plastic food wrap, shrink wrap, garden hoses, shoe soles
LDPE (low density polyethylene) offers clarity and flexibility. It is used to make bottles that require flexibility. To take advantage of its strength and toughness in film form, it is used to produce grocery bags and garbage bags, shrink and stretch film, and coating for milk cartons.Examples: Squeeze bottles, dry cleaning bags
PP (polypropylene) has high tensile strength, making it ideal for use in caps and lids that have to hold tightly on to threaded openings. Because of its high melting point, polypropylene can be hot-filled with products designed to cool in bottles, including ketchup and syrup. It is also used for products that need to be incubated, such as yogurt. Many Cambo, Tupperware and Rubbermaid food storage containers are made from PP.Examples: Bottle caps, take-out food containers, drinking straws
PS (polystyrene), in its crystalline form, is a colorless plastic that can be clear and hard. It can also be foamed to provide exceptional insulation properties. Foamed or expanded polystyrene (EPS) is used for products such as meat trays, egg cartons and coffee cups. It is also used for packaging and protecting appliances, electronics and other sensitive products.Examples: Plastic foam, packing peanuts, coat hangers
Other denotes plastics made from other types of resin or from several resins mixed together. These usually cannot be recycled.
Removing Odors And Stains From HDPE Buckets
Wash the bucket inside and out with warm, soapy water, then rinse.
Pour 1 cup of baking soda into the bucket and fill with warm water all the way to the top. Stir to dissolve and let it sit for a couple of days in a warm location.
Empty the bucket, then pour in 1 cup of bleach and fill with warm water all the way to the top. Stir to mix, then let it sit for a couple of days in a warm location.
Rinse thoroughly multiple times, replace the lid and let it sit for a few days. Carefully remove the lid and take a whiff. If you can still smell the remnants of what was in there, the bucket is probably of no use as a fermenter.