The Difference Between Supermarket-Grade Food Storage Bags and Household-Grade Food Storage Bags

[Household Food Storage Bags]

PE and PVDC food storage bags are relatively safe. PE is primarily used for packaging fruits and vegetables, while PVDC is mainly used for packaging deli meats, ham, and similar items. Although PVC food storage bags are widely used for packaging food and vegetables, they pose certain potential health risks. These risks stem primarily from two sources: first, the residual levels of vinyl chloride monomer in the product (the safety limit for vinyl chloride in humans is less than 1 mg/kg); and second, the types and concentrations of processing aids used during manufacturing. Two substances in PVC are potentially carcinogenic: VCM (vinyl chloride monomer) and DEHA (a plasticizer). While VCM is non-toxic at concentrations within 1 ppm (parts per million), levels exceeding this threshold may pose a carcinogenic risk. Additionally, plasticizers can leach out at high temperatures and be harmful to human health. Consequently, in 2005, the General Administration of Quality Supervision, Inspection and Quarantine strictly prohibited PVC manufacturers from using plasticizers and banned the use of PVC food storage bags for packaging meat, deli meats, tofu, and other ready-to-eat foods.

When selecting food storage bags, pay attention to the following points:　　1. Check the material listed on the product label: Polyethylene (PE) bags are now widely used for food packaging; polypropylene (PP) bags, which are highly transparent, are mainly used for packaging bread and snacks; polyvinyl chloride (PVC) bags can also be used for packaging perishable foods such as vegetables and fruits, but they must not be used for oily foods or for heating in a microwave oven.

2. When heating food in the microwave, use food storage bags labeled “microwave-safe.”　　3. For refrigerated and frozen foods in the refrigerator, use food storage bags instead of ordinary plastic bags. The special manufacturing processes and materials of food storage bags or wraps provide good breathability and preservation properties, whereas ordinary plastic bags cause food to spoil and deteriorate after a short period of use, failing to achieve the purpose of preservation. 　　4. It is best to use clear, transparent food storage bags.

【Food Storage Bags Used in Supermarkets】

These are not called food storage bags but rather tear-open bags, also known as continuous-roll bags. Commonly found in supermarkets, they are used to package fresh foods such as deli meats, fruits, rice, and flour.

Tear-open bags are divided into two categories based on material. Those used for packaged deli meats must meet national food safety standards, while those for non-food items (such as groceries) are typically supplied by the manufacturers themselves. It is understood that most non-food tear-open bags are made of PE material with added calcium carbonate (industrial lime powder), which is low-cost and inexpensive. However, if such continuous-roll bags are used for food packaging, they can be harmful to human health.