Food plastic blister boxes are plastic blister trays for vegetables and fruits. Sometimes they need to be refrigerated,  and sometimes heated in microwave ovens. Usually PP or PET materials are used to make this kind of blister boxes.

So what are the differences between PP and PET?

In color, the common color of PP is white, black or natural color (milky white). In thin sheet plastic absorption, PP is not transparent.
PET materials are usually transparent, rarely to make it black or white.

In physical properties, PP melting point reaches 167 ℃, and PP tray can be put into the microwave oven , but it also can withstand the low temperature of -35 ℃. So PP plastic tray is very suitable for cooked food, cold meat, seafood and other foods that need to be heated or refrigerated.
The PET material is easy to deform when heated to 70 ℃, and will have harmful substances when at this temperature. Therefore, the PET plastic blister box is only suitable for fruit, vegetable salad and other things that can be used without heating.

Therefore, as a food-grade material, PP can not only be heated in microwave oven, but also be refrigerated in cold storage. It can withstand both high temperature and low temperature. It is a good choice for packaging food.