Is Canned Food Still Safe To Eat After Being Left In A Hot Car?

Forgetting a grocery bag in the car on a hot summer day is an easy mistake, but it could cost you more than just your fresh food. Canned food is designed and sold to be shelf-stable, but that stability actually depends on certain conditions. Once temperatures creep past a certain point, things start to change — and not in a good way.

Temperatures over 100 degrees Fahrenheit can be detrimental to canned foods. In fact, according to most food safety guidance, one of the rules for storing canned food is that it should be kept below 85 degrees Fahrenheit and in a cool, dry place. So if you've left your car parked in the sun too long, the temperature inside the vehicle can easily blow past that, especially in the summer. However, don't assume all your food is automatically destined for the trash. This is a contextual risk; you need to consider just how hot the car got and for how long, as prolonged exposure to heat is what increases the chance of spoilage.

Let's assume you've left some canned goods in a hot car and now you want to know if you can still eat them. The tricky thing is, not all spoilage will be obvious at first glance, so you need to know what the warning signs are. A bulging exterior is one of the biggest red flags that canned foods are inedible, so if the lid or sides look puffed out, then you know that gas is present inside the can, which is an indicator that bacteria is growing. 

However, not every type of bacteria will give off gas, so bulging alone is not enough of a sign. Leaks, rust, and dents can signal similar trouble. While minor rust that can be easily wiped off is not necessarily a cause for concern, heavily rusted canned food can be dangerous. And finally, if when you open the can the contents spurt out or smell foul then that's an immediate no as well.

Even if you feel like your food is safe to eat, the heat may have compromised its quality. Exposure to high temperatures can cause food textures and flavors to change and nutrients to break down, even if it doesn't make it dangerous to consume. A can is a tough exterior, but it turns out, it isn't as invincible as it seems -– at least not if heat has anything to say about it.