Soup bags, or plastic food bags, are widely used in our daily lives due to their convenience and versatility. However, most people might lack an accurate understanding of the proper and safe use of plastics. Hence, it’s crucial that we familiarize ourselves with the types of plastic bags commonly used today.

Clear PP (Polypropylene) Hot Bags or Soup Bags

Clear, shiny, and thin, this plastic type can withstand temperatures up to 100°C and is more resistant to moisture and air permeability than opaque hot bags.

Suitable for hot foods such as hot soymilk, porridge, or noodles, they can also store dry foods for several days due to their adequate moisture resistance.

A word of caution: These bags aren’t suited for freezer use as they are not cold-resistant and may rupture.

HDPE (High-Density Polyethylene) Bags or Opaque Hot Bags

Thick and can withstand temperatures up to 100°C and cold temperatures down to 0°C, this plastic type is a superior choice to clear hot bags for cold resistance. Suitable for general food storage, whether dry or slightly moist, these bags are resistant to acids and chemicals.

Ideal for uses requiring strength, such as plastic bags in convenience stores or for temporary food storage.

A word of caution: They should not be used for long-term food preservation as they do not adequately prevent air permeation, leading to potential odors or oxidation reactions. Avoid using them with hot food as they may melt and deform.

Low-Density Polyethylene (LDPE) Bags or Cold Bags

Clear but not very shiny, they are soft, sticky, flexible, and resilient against twisting and turning. These bags are leak and chemical resistant and are excellent at retaining moisture. Although not heat resistant, they can withstand cold temperatures down to -40°C and be put in the freezer without tearing or cracking.

Ideal for foods requiring cold storage, such as frozen foods, fresh vegetables, fresh fruits, seafood, and raw meats. They are also used in transporting goods that require flexibility, such as plastic bags in packaging raw pharmaceutical materials or goods that require a cool environment when long-distance delivery and product freshness is crucial.

A word of caution: These bags should not be used for hot items.

Management: Separate the food scraps, wash, dry, and store them properly before sending them off for recycling. If the bags are heavily contaminated, they can be sent for Refuse-Derived Fuel (RDF) processing.

Did you know!?

Most soymilk shops commonly use opaque soup bags to put hot brewed drinks and steamed warm foods. Given the properties of plastics, they should consider switching to clear hot PP bags, which have better heat resistance.

Choosing the right plastic bags and using them correctly is crucial. Not only does everyone benefit from the convenience and preservation of food freshness, but it also helps to reduce health impacts and risks. It aids in reducing waste both from the use of plastic bags and food waste. And let’s not forget, proper disposal of used plastic bags is essential for maintaining a sustainable and livable environment.