Do not put MCT oil, perilla oil, etc. in expanded polystyrene container! Such oil can transform and damage the container

An expanded polystyrene container is made of foamed polystyrene. It's light-weighted, tough and cushioned. Due to its low thermal conductivity and high preserving quality, it is often used for containing instant noodles and prepared food.

In about five years from fiscal 2018, PIO-NET¹ received six complaints about expanded polystyrene bowls used for instant noodles with soup. It was reportedly said that the bowl was damaged after pouring hot water on instant noodles and adding oil such as MCT or perilla oil and that hot water leaked from the damaged bowl. One of the consumers was scalded with hot water leaked from the bowl.

Instant noodle bowl products provide precautionary information on its package stating that any other edible oils except for the included oil shall not be added because certain oils can transform and damage the bowl.² Some edible oil products provide precautionary information on its package stating that the oil shall not be put in a polystyrene food container.²

Therefore, NCAC decided to check labeling for some instant noodle bowl products and some oil products (MCT oil, coconut oil, perilla oil, and linseed oil) and to conduct reproduction tests by pouring hot water and putting sample oil in expanded polystyrene bowls in order to issue a consumer alert.

1. ¹ PIO-NET is a database that collects information on inquiries concerning consumer affairs by linking NCAC with local consumer affairs centers and similar organizations across Japan via an online network.
2. ² Although it is not legally required to provide such precautions under the Food Labeling Act, the instant noodle industry provides consumers of the precautions on a voluntary basis.

Cases registered with PIO-NET

• When I was about to eat instant noodles after pouring hot water and adding MCT oil almost at the same time, the bottom fell out of the bowl and hot water fell on my legs. It was hot, but my legs were not scalded.
• When I added MCT oil to two types of instant noodles, each bowl was damaged. The content leaked out of the bowl and I couldn't eat the noodles.
• When I was about to eat instant noodles, hot water oozed out of the bowl and dripped down. The manufacturer examined the cause and found that MCT oil such as coconut oil adhered to the inside of the bowl and the bowl got thinner and weaker, as a result of which the bowl was broken.

Findings

Labeling and representation

Labeling and representation of instant noodles in expanded polystyrene bowls

• All the tested products come with a precautionary label on the main body stating that any other edible oils except for the attached oil shall not be added.
• All the examined manufacturers and sellers provide information on their websites stating that any other edible oils except for the included oil shall not be added.

Labeling and representation of tested edible oil

• Most of the tested edible oil products provide information on the main body that the oil shall not be put in expanded polystyrene containers (e.g. instant noodle bowls, coffee cups, etc.), while the others do not provide such information.
• About half of the edible oil products provide information on websites of manufacturers and sellers that the oil shall not be put in expanded polystyrene containers (e.g. instant noodle bowls, coffee cups, etc.).

Reproduction test on how expanded polystyrene bowls are transformed and damaged

• When tested edible oil was added three minutes after pouring hot water in a bowl, the bowl was damaged or the inner surface was transformed in some cases.
• When hot water was poured in the bowl soon after tested edible oil was put therein, the expanded polystyrene surface was transformed more broadly.

Advice for consumers

• If certain oil such as MCT or perilla oil is put in an expanded polystyrene container (e.g. instant noodle bowl, coffee cup, etc.), the container can be transformed and damaged. Do not add any other edible oils except for the attached oil.

Video

Video: Do not put MCT oil, perilla oil, etc. in expanded polystyrene container! (Japanese version)

Request to busisnesses

Provide precautionary information on the main body in an eye-friendly way to prevent expanded polystyrene containers from being transformed and damaged. Further raise consumer awareness on the risk of putting certain oil in an expanded polystyrene container.