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.
But most backpackers are doing more than just slightly heating a Ziploc. What happens if you add near-boiling water to one? “There is the possibility of polypropylene breakdown at these temperatures, with more leaching of plastic byproducts… into foods, particularly fatty foods. We don’t know what the long term effects of these compounds are in humans,” said Lonky.
If you dehydrate your own backpacking food, you probably package individual servings in quart-size freezer bags. Not only are Ziplocs a lightweight, low-bulk way to pack food, but they also make for mess-free cooking. Just add hot water directly to the bag and wait for your food to soften.
Kirkconnell isn’t personally concerned about the safety of cooking in a freezer bag. “Even when I was backpacking constantly, I was only eating one meal a day out of a bag, and that was for, say 2-3 weekends a month or a five-day trip here and there. People drink and eat out of plastic nearly daily, not realizing it,” such as the plastic linings in disposable coffee cups and many canned foods and beverages.
Kirkconnell hoped to develop a cheaper, tastier, more convenient alternative to commercial backpacking food. “I wanted to be able to hike long miles and not be cleaning up pots in the dark, or wasting fuel… I wanted to be able to eat meals I liked and not go broke.”
Companies like SC Johnson, the makers of Ziploc bags, don’t have to disclose every ingredient in their products. For that reason, we can’t know exactly how all components in a freezer bag might react to hot water, even though the EPA considers polypropylene generally safe. Further complicating matters, some studies indicate that polypropylene toxicity can vary based on the manufacturing process.
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 theyre 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.
Survival Tip – Boiling water in a plastic bag
Can you put boiling water in a ziploc bag?
You should not pour boiling water into a Ziploc bag. The high temperature can cause the material to break down and leech microscopic plastic particles into the food. While Ziploc bags are dioxin free, chlorine-free, and do not contain BPA, it’s safer to avoid ingesting plastic particles on a regular basis.
Can You boil food in a ziploc bag?
Yes, it is safe to boil food in a Ziploc bag, as long as you make sure that you choose a freezer bag, as they are the strongest and less likely to tear or leak when used for boiling. Are Ziploc bags safe for sous vide?
Can You boil eggs in a ziploc bag?
Kindly don’t place the bags in boiling water; it can damage their structure and make them more susceptible to growing bacteria. If you boil the bag, it will expand, causing it to burst and leak. It may even expose your food to dangerous chemicals used in making plastics.
Why do you need a ziploc bag for cooking?
The Ziploc bag keeps the food and all the ingredients in one place while it’s cooked in boiling water. Cooking times will vary depending on cooking, but most meats will need to cook for several hours. Putting your food inside a Ziploc bag ensures that your food will be cooked evenly throughout with all the flavours sealed in.