If you were going to a party, would you really want to eat or drink from something meant to hold garbage?
Is it OK to use brown paper grocery bags to prepare snacks? I’d like to use one to shake powdered sugar on a cereal snack. I’ve heard you can cook in them, too. Is that right?”
“Is it safe to make omelettes by boiling the egg mixture in a Ziploc bag? I want to make them for a camping trip.”
“Is it safe to use terra cotta flowerpots for baking bread and cakes? The cakes look so cute in these containers!”
“I have a brand new galvanized garbage can. It has never held trash. Can I use it to serve punch?”
I could go on and on with the questions I’ve received through the years about various unusual containers used to prepare, cook and serve food. The questions especially seem to pop up in the spring as people plan parties or head out to campsites.
The No. 1 rule for answering any of these questions is to consider the original purpose for the container. Was the container meant to prepare or serve food, with the food in direct contact with the container?
Containers that are “food grade” must meet higher standards for sanitation and safety.
Let’s consider each of the containers mentioned in the previous questions and the potential food safety issues.
Brown paper grocery bags: Yes, brown paper grocery bags are intended to hold food. However, the food typically placed in brown paper bags is in packages or containers. Grocery bags are not a sanitary container for mixing or coating snacks with powdered sugar. Instead, use a bowl or a zip-type plastic bag.
Grocery bags are not recommended for cooking, either. The bag may ignite and cause a fire in the oven. The ink, glue and recycled materials can emit toxic fumes. Use oven cooking bags or a pan instead.
Plastic bags: Boiling omelettes in a Ziploc bag has been something of a fad the last few years. When I first received the question, I directly contacted a staff member at the company’s consumer help line. The company representative
told me that Ziploc-brand bags cannot be used to boil food. The bags are made from polyethylene plastic with a softening point of about 91C (195F). Therefore, they could melt when exposed to 100C (212F).
Some companies produce “boilable” plastic bags that can be used to cook foods. Read the manufacturer’s statement to learn about their suggested use. Don’t push the limits.
Tera cotta flowerpots: Some clay containers are designed for food use. However, clay pots from the gardening centre are not meant to be in direct contact with food. The clay in garden pots may contain heavy metals, such as lead. Some may crack or break in the oven, too. If you completely line a clay pot with food-grade material, such as aluminum foil, you can use it to serve food. Better yet, before serving food in it, line the pot with a smaller container from your kitchen cabinet.
Galvanized trash cans, plastic trash cans or any type of trash can: If you were going to a party, would you really want to eat or drink from something meant to hold garbage? Obviously, trash cans were not meant to serve food, so the plastic or metal used to make them is not food grade. Chemicals from the plastic or metal may leach into the food. Acidic foods, such as punch, can pull harmful chemicals from the container into the beverage.
– Julie Garden-Robinson, PhD, L. R. D., is a North Dakota State University
Extension Service food and nutrition specialist and associate professor in the
department of health, nutrition and exercise sciences.