Is It Safe to Cook With Plastic Bags?

And Other Sous Vide Questions, Explained – Food safety 101.

After we shared a ton of new sous vide recipes recently, one of the most common reader comments was about plastic bag safety. I hear you. I spent a year in college living with a host family in France, and on my first night, I walked to the stove to find a salmon filet in a plastic bag, submerged in a pot of hot water. My first thought was that I’d get cancer, my second was that I’d get botulism. I didn’t know what else to do so I ate the salmon and waited for the poison to set in.

It didn’t, and I lived to tell the tale of sous vide plastic bag safety. The key to sous vide, which is French for “under vacuum,” is putting a protein, often meat, in a plastic bag and removing all the air. This is the part that raises questions for risk-averse home cooks, and we’ll try to answer them below.

Is cooking with plastic safe?

When it comes to cooking, there’s very bad plastic and, uh, not-as-bad plastic. The bad plastic is polycarbonate, which releases the chemical Bisphenol A (BPA). This kind of plastic is found in cling wrap, plastic squeeze bottles, take-out containers, multi-gallon water bottles, and plastic plates. The not-as-bad plastics do not release BPA and count high-density polyethylene, low-density polyethylene, and polypropylene among their ranks. The reason they’re not necessarily “good” plastics is because a 2011 study found that when some were heated, these plastics —in fact, most plastics on the market, including those advertised as BPA free—release non-BPA chemicals that disrupt hormone activity. The amount of chemicals released, however, is unknown.

Read more: What kind of plastic bags are safe for sous vide?