Food-grade material standards for plastic tableware

The food-grade material standards for plastic tableware mainly involve aspects such as material safety, temperature resistance, and chemical stability. The following is a detailed introduction:

Common food-grade plastic materials

PET (Polyethylene terephthalate)

Common uses: mineral water bottles, carbonated beverage bottles, juice bottles, etc.

Characteristics: It can only withstand heat up to 120℃. It is only suitable for cold and warm drinks. If it is used to hold high-temperature liquids or heated, it will deform. Because it can only withstand heat up to 70℃, it may produce carcinogens after being used at minus 20 ℃ for about ten months. Therefore, it should be used up and discarded at one time, and it is not recommended to use it as a water cup to hold water.

HDPE (High-density Polyethylene)

Common uses: Suitable for bottles of food and medicine, cleaning products and bath products, shopping bags, trash cans, etc. Plastic bags marked as food-grade can be used to hold food. Plastic containers for cleaning supplies and bath products can be reused after careful cleaning, but these containers are usually difficult to clean and it is best not to reuse them.

PVC (Polyvinyl chloride)

Characteristics: When exposed to high temperatures or in contact with oils, polyvinyl chloride (PVC) plastics tend to release phthalates and incompletely polymerized toxic vinyl chloride monomers. The cling film made of polyvinyl chloride has good transparency, is not easy to break, has strong adhesion and is low in price. However, it is only suitable for the refrigeration and preservation of vegetables and fruits, and should not be used to store meat, cakes and other foods with high fat content, nor should it be used for heating in a microwave oven.

LDPE (Low-density Polyethylene)

Common uses: Paper milk cartons, beverage boxes and other packaging boxes all use it as the inner film. This material is also commonly used in cling film, plastic film, etc.

Characteristics: It will melt when the temperature exceeds 120℃. If this cling film is used to wrap food and heat it, the oil in the food will dissolve some components in the cling film. Therefore, the cling film should be removed before putting it in the microwave oven. At least, the food should not come into direct contact with the cling film.

PP (Polypropylene)

Common uses: food-specific plastic bags, food plastic boxes, food straws, microwave lunch boxes, etc.

Characteristics: Safe and non-toxic, with excellent low-temperature and high-temperature resistance. It is the only plastic that can be heated in a microwave oven and has high strength and folding resistance. It will not break even after 50,000 drops at -20 ℃ from a height. It has a relatively high operating temperature and can be used to hold hot water or heat rice without deforming. After careful cleaning, it can be reused. However, for some microwave lunch boxes, the box body is made of PP, but the lid is made of other materials that are not heat-resistant. Therefore, they should not be put in the microwave together with the box body. To be on the safe side, the lid should be removed before putting the container in the microwave.

PS (Polystyrene)

Common uses: bowl-shaped instant noodle boxes, fast food boxes, disposable food packaging boxes, etc. Food-grade PS sheets are often used in containers such as yogurt cups.

Characteristics: It has excellent cold resistance, but when the temperature is too high, it will release harmful substances. Therefore, do not heat the bowl of instant noodles in the microwave oven, and try not to use it to hold extremely hot food. At the same time, it should not be used to hold strong acidic substances (such as fruit juice) or strong alkaline substances, otherwise styrene and auxiliary materials will be released.

PC (Polycarbonate)

Common uses: It is often used to make kettles, water cups, baby bottles, etc.

Characteristics: It has excellent impact toughness and mechanical strength, and is highly transparent, earning it the title of "transparent metal". However, during the production of PC, the raw material bisphenol A should completely become A structural component of the plastic and should not be released during use. But in reality, this is often not achieved. A small amount of bisphenol A does not fully convert into the plastic and will be released into food when exposed to heat. Bisphenol A is an endocrine disrupster that is particularly harmful to developing fetuses and children. It may cause miscarriage, congenital intellectual disability and delayed intellectual development in infants and young children. Some studies have also confirmed that bisphenol A can interfere with and antagonize thyroid hormones. Therefore, extra caution should be exercised when using it.

General requirements for food-grade plastic materials

Migration quantity requirements: The test method for the total migration amount of food contact materials is the total amount of all volatile substances that migrate from the food contact materials and products to the food mimics they come into contact with. It is expressed in milligrams (mg/kg) of non-volatile migrating substances per kilogram of food mimics or milligrams (mg/dm²) of non-volatile migrating substances that migrate out per square meter of contact area. Food contact material products specifically for infants and young children are expressed in mg/kg. There are also corresponding regulations on the maximum allowable amounts of all non-volatile substances that can be transferred from food contact materials and articles to food simulants in contact with them. The specific migration quantity test method is the maximum allowable amount of a certain substance or a certain type of substance that can migrate from food contact materials and products to the food or food mimics they come into contact with, and it also has a specific expression. The residue testing method is to determine the amount of a certain or a certain type of residue substance in food contact materials and products. The maximum residue testing method stipulates the maximum allowable amount of a certain or a certain type of residue substance in food contact materials and products.

Requirements for non-intentionally added substances: For food contact materials and products, substances that are not artificially added, including impurities brought in by raw and auxiliary materials, decomposition products, contaminants, and residual intermediate products during production, operation, and use, the production enterprise should control them to ensure that the amount they migrate into the food meets the corresponding standard requirements. For substances that do not come into direct contact with food and have effective barriers between them, and are not included in the corresponding national food safety standards, food contact material and product manufacturers should conduct safety assessment and control on them to ensure that the amount they migrate into food does not exceed 0.01mg/kg. Carcinogenic, mutagenic substances and nanomaterials are not subject to the above principles and should be implemented in accordance with relevant laws and regulations.

Usage requirements: When food contact materials and products come into contact with food under the recommended usage conditions, substances that migrate into the food should not cause changes in the food's composition, structure, or properties such as color, aroma, and taste, nor should they exert technical functions on the food (except where otherwise specified). The substances used in food contact materials and products should be used in as little as possible under the premise of achieving the expected effect, and should meet the corresponding quality specification requirements.

Precautions for the purchase and use of plastic tableware

When making a purchase

Check the packaging labels: Plastic tableware products are subject to license management. When purchasing, first check if there are relevant marks on the outer packaging or label. According to China's national food safety standards, food-related products need to be labeled with the product name, material, name, address and contact information of the manufacturing enterprise, production date and shelf life, etc.

Check the appearance of the product: Choose products with a smooth and flat surface and no obvious defects. Try to select colorless and transparent products without decorative patterns. At the same time, you can first smell to see if there is any strange smell or odor to prevent the product from mixing with food during use and affecting food safety.

When in use

Pay attention to the usage temperature and heating method: The usage temperature of tableware made of different materials varies, and whether it can be heated in a microwave oven also differs. Try to choose tableware made of PP and check the label or instructions before use. For instance, some microwave lunch boxes have their bodies made of PP, but their LIDS are made of other materials that are not heat-resistant. Therefore, they should not be placed in the microwave together with the body. To be on the safe side, the lid should be removed before putting the container in the microwave.

Pay attention to the type of food to be served: Different food components have requirements for lunch boxes. Generally, it is recommended to use plastic tableware to hold food with low oil content. This is because some harmful components in plastic are more likely to leach out under the condition of oil, which may have a chemical reaction with the lunch box, posing a hidden danger to public health and food safety.