Among the many materials we use in the kitchen, and which come into contact with our food every day, there are plastic containers. We use them practically always, due to various needs: bringing lunch to the office, storing food in the fridge or the freezer, storing dry ingredients (such as garlic, salt or pepper). Among the plastic box for food (กล่อง พลาสติก ใส่ อาหาร, which is the term in Thai), however, some are suitable for anything concerning food, so they have a wider use.
With PET (polyethene terephthalate, number 1) transparent bottles and containers are made for water, soft drinks and food. This type of food-grade plastic is safe when used to contain cold products. Heat favours degradation which can release harmful substances with antimony and acetaldehyde. These containers are designed to be essentially disposable, therefore, they should not be reused for long.
The PE (high-density polyethene or HDPE, number 2) is a plastic food-safe and resistant, used for non-transparent objects such as corks, yoghurt pots, containers for milk and also for detergents. It resists hot food quite well and is always preferable to PET.
The PVC (polyvinyl or V, Number 3) is potentially dangerous because it releases phthalates. If you burn free dioxin, also for this you are trying to replace it with other materials. Due to its resistance, it is generally used to make advertising banners, banners and outdoor coverings. It can also be present in transparent films to wrap food, even if its presence in food materials is increasingly rare.
The plastic LDPE (low-density polyethene, number 4) is used to manufacture bags to freeze and disposable gloves, such as those for handling the vegetables in supermarkets.
PP (polypropylene, number 5) is a plastic considered safe. It is used for non-transparent bottles, lunch box (กล่อง ข้าว, which is the term in Thai) and trays with lids. To reuse these containers, it is good to follow the manufacturer’s instructions, even if in general the lighter and cheaper items are to be intended as disposable.
PS (polystyrene or polystyrene, number 6), an excellent thermal insulator, is used above all for takeaway containers. The harmfulness of polystyrene is not universally recognized since it is not certain whether the harmful substances are released from the material. The PS, however, cannot be considered a completely safe food plastic.