1. Polyethylene terephthalate (PET), which is made of ethylene. It is often used as a mineral water bottle, cola bottle, juice bottle, etc. Because it can only withstand heat of 120¡ãC, it is only suitable for cold and warm drinks. If it is filled with high-temperature liquids or heated, it will deform.

Introduction

According to its composition, plastic tableware can be divided into the following types:

1. High-density polyethylene (HDPE), suitable for bottles for food and medicine, cleaning supplies and bath products, shopping bags, and trash cans.

2. Polyvinyl chloride (PVC), which is polymerized from vinyl chloride. Polyvinyl chloride plastics are prone to release phthalates and incompletely polymerized toxic vinyl chloride monomers at high temperatures and in contact with grease. The cling film made of polyvinyl chloride has good transparency, is not easy to break, has strong adhesion, and is low in price. The film that sticks firmly to the boxes we see in supermarkets and hypermarkets is it. According to its characteristics, it is only suitable for the refrigeration and preservation of vegetables and fruits. It is not suitable for meat, cakes and other foods containing more fat, nor for microwave heating.

3. Low-density polyethylene (LDPE) plastic film and cling film have good water barrier properties, so paper milk cartons, beverage cartons and other packaging boxes use it as the inner film. Because low-density polyethylene cling film will melt when it exceeds 120¡ãC, if the cling film is used to wrap food and heat it, the fat in the food will melt some components in the cling film. Therefore, the cling film must be removed before entering the microwave oven, at least the food cannot be directly in contact with the cling film. Low-density polyethylene itself does not have degradable properties, and the current "plastic restriction order" mainly restricts it.

4. Polypropylene (PP), which is made of propylene polymerization, has better transparency than polyethylene and is harder than polyethylene. Most of the boxes used for packaging in restaurants are made of it, and the plastic boxes made of it can be heated in the microwave.

5. Polystyrene (PS), which is made of styrene polymerization, is often used in bowl instant noodle boxes and fast food boxes. It is heat-resistant and cold-resistant, but harmful substances will be released when the temperature is too high, so do not put the bowl instant noodles in the microwave to heat them, and try not to use it to hold hot food. At the same time, it cannot hold strong acidic (such as juice) and strong alkaline substances, otherwise styrene and auxiliary materials will be released.

6. Polycarbonate (PC), which is synthesized with bisphenol A and diphenyl carbonate as raw materials, has excellent impact toughness and mechanical strength, and has good transparency, so it is known as "transparent metal". It is often used to make kettles, water cups, baby bottles, etc. In the process of making PC, the raw material bisphenol A should completely become a plastic structural component and should not be released during use, but in fact it is often not possible. A small part of bisphenol A cannot be completely converted into plastic and will be released into food when heated. Bisphenol A is an endocrine disruptor, which is particularly harmful to developing fetuses and children, and may cause miscarriage, congenital intellectual disabilities and intellectual retardation in infants and young children. Some studies have also confirmed that bisphenol A can interfere with and antagonize thyroid hormone and inhibit the secretion of testosterone, affect the sexual development of boys, hinder the formation of sperm, and thus may affect fertility. Therefore, special care should be taken when using it, including milk bottles made of polycarbonate, so as not to harm the sexual development of infants.

In addition, melamine plastic, which is not included in the above 7 types of plastics, is also a common tableware used by residents, restaurants, and unit canteens. It is a thermosetting plastic that is often used to make tableware such as bowls, plates, chopsticks, and spoons. It is made of melamine and formaldehyde resin as the main raw materials, with an appropriate amount of cellulose filler and auxiliary materials such as colorants. Its appearance and feel are like porcelain, acid and alkali resistance, high surface hardness and impact resistance, long service life, and it can be cleaned and disinfected in a dishwasher below 120¡ãC. For tableware of the same size and thickness, melamine tableware is lighter than porcelain tableware, but not as easy to break as porcelain, so it is especially popular with parents of infants and young children. Due to the particularity of the molecular structure of melamine plastic, it is not suitable for use in microwave ovens, otherwise it is easy to crack. If the melamine in melamine tableware is not completely polymerized, some of it will melt into the food. "Melamine tableware" made of urea-formaldehyde resin or phenolic resin has been seized on the market. Its appearance is very similar to authentic melamine tableware, and it is not easy for ordinary people to identify it, but it contains high formaldehyde, especially after heating or storing "boiling" food. It is more likely to precipitate, so you should go to a regular store to buy melamine tableware produced by an authentic factory.

Purchase Identification

Only those with complete label instructions can be trusted

When purchasing plastic tableware, first check whether the label is complete, and then look at the product. The surface of the product should be smooth, without stains, impurities, scratches, cracks, etc., and there should be no discoloration or fading. You can also smell it to see if there is any irritating smell or other odors. The most important thing is to look at the product label. The standard stipulates that the product must indicate the manufacturer's name or trademark, material, use temperature and other instructions. If the product has requirements such as not resistant to hot water, not suitable for microwave ovens, and cannot contact oil, it should also be marked. "This standard is clear, if it is not marked, it will be considered usable."

Current situation: The label is not fully standardized and the quality is uneven

There are many varieties of microwave tableware, but the labels are different. Some indicate the use temperature and method of use, some only indicate the use temperature, and some do not mark the use temperature or any instructions for use. Guangdong is a region where thermoplastic tableware manufacturers are concentrated and a major distribution center, but due to the lack of unified standards, the quality of products on the market varies greatly, and some companies use low-quality and low-priced products to seize the market.

Use: Only short-time heating below 700W is recommended

Generally speaking, products on the market with a temperature of 140¡æ are relatively safe. However, even microwave plastic tableware that has passed the standard test is only recommended for use under short-time heating conditions below 700W, unless the product is marked for cooking or has obtained other international certifications with higher requirements, it can be used under more stringent conditions.

700W is roughly equivalent to the mid-range firepower of a microwave oven. Generally, the instruction manual contains output power instructions corresponding to each level of firepower. Short-time heating refers to heating for 2 to 3 minutes and cannot be used for cooking cooked food. Internationally, utensils used for short-time heating and cooking are different. Plastic tableware made of two materials can be used for cooking in Europe and the United States, but they are rare in the Chinese market.

Safety distinction

There is a triangle with an arrow at the bottom of each plastic product, which is the "recycled" sign. There are Arabic numerals from 1 to 7 inside. The different Arabic numerals represent the different properties and uses of this plastic material. It is like the identity certificate of plastic products.

The number "1" means that the material of the plastic is PET, that is, polyethylene terephthalate, which is commonly found in mineral water bottles, carbonated beverage bottles, etc. It is heat-resistant up to 70¡ãC, easy to deform, and has substances that are harmful to the human body dissolved; after 10 months of use, it may release the carcinogen DEHP; it cannot be placed in the sun in the car, and cannot be used to hold substances such as wine and oil. Bottles with this logo cannot continue to hold water after use. Please throw them in the recyclable trash can and let them be recycled.

The number "2" means that the material of the plastic is HDPE, which is commonly found in packaging bottles for cleaning products and shower products. It is not used for food packaging.

The number "3" means that the material of the plastic is PVC. This material is prone to produce harmful substances at high temperatures, and it will even be released during the manufacturing process. After the toxic substances enter the human body with food, they may cause breast cancer, congenital defects in newborns and other diseases. Containers of this material are rarely used to package food. If used, never let it heat up.

The number "4" means that the material of the plastic is LDPE. The general products are plastic wrap, plastic film, etc. The heat resistance is not strong. Usually, qualified PE plastic wrap will melt when the temperature exceeds 110¡æ, leaving some plastic preparations that cannot be decomposed by the human body. In addition, when the food is wrapped in plastic wrap and heated, the fat in the food can easily dissolve the harmful substances in the plastic wrap. Therefore, before putting the food into the microwave, the plastic wrap wrapped around it should be removed first.

The number "5" means that the material of the plastic is PP. High temperature resistant, often seen in microwave lunch boxes. It can be reused after careful cleaning. It is necessary to pay special attention to the fact that some microwave lunch boxes are indeed made of No. 5 PP, but the lid is made of No. 1 PE. Since PE cannot withstand high temperatures, it cannot be put into the microwave together with the box body. To be on the safe side, remove the lid before putting the container into the microwave.

The number "6" means that the material of the plastic is PS. It is often seen in bowl-shaped instant noodle boxes and fast food boxes. It is heat-resistant and cold-resistant, but it cannot be put into a microwave oven to avoid releasing chemicals due to excessive temperature. It cannot be used to hold strong acids (such as orange juice) and strong alkaline substances, because it will decompose polystyrene, which is not good for the human body and is easy to cause cancer. Therefore, you should try to avoid using fast food boxes to pack hot food.

The number "7" represents the material of the plastic other than PVC and polystyrene or a synthetic material of multiple plastic materials. It is more common in kettles, water cups, and baby bottles. It is resistant to high temperatures and can be used repeatedly, but it cannot be heated in a microwave oven.

After distinguishing the different materials and uses of plastics, you might as well conduct a major inspection of your plastic tableware and remove those plastic tableware that are harmful to health. In daily life, when buying cooked food, snacks and other foods that are eaten directly, it is best to bring your own tableware or standard plastic food bags. Disposable plastic lunch boxes or plastic bags outside will penetrate toxic substances into the food. Refrigerated and frozen foods in the refrigerator should also be wrapped with plastic wrap or fresh-keeping bags, and do not use ordinary plastic bags instead. It is best to use porcelain cups, porcelain bowls or glass cups and glass bowls for daily drinking and eating.

Cleaning method

1. Milk deodorization method: First clean it with detergent, then pour two tablespoons of fresh milk into the plastic tableware, cover it, shake it, so that every corner of the cup is in contact with the milk, for about one minute, and finally pour out the milk and clean the plastic tableware.

2. Orange peel deodorization method: First clean it with detergent, then put fresh orange peel into it, cover it, and rinse it for about 3 to 4 hours.

3. Use waste tea leaves to deodorize. If there is a fishy smell in the plastic tableware, first scrub it with waste tea leaves, then rinse it with clean water, and the fishy smell will be removed.

4. Soak it in salt water for 30 minutes.

If the above methods cannot remove the odor of plastic tableware, and the plastic tableware emits a strong pungent odor when it is rinsed with hot water, consider not using this plastic tableware to drink water. The plastic material of the plastic tableware may be poor, and drinking water with it may be harmful to your health. It is safer to give up and replace it with a plastic tableware.

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