Work at home, study at home, exercise at home. Cook at home.

As millions of people around the world try to keep a safe distance from one another, they are also cooking, prepping, and eating meals in their homes more than ever. 

Darin Detwiler, an assistant teaching professor of food policy at Northeastern, joined News@Northeastern for a live Facebook interview to offer his insights into how to prioritize food safety at home, and how that contributes to protecting others during the pandemic.

Cooking at home can be one of the best ways to try to help reduce the spread of the coronavirus that causes COVID-19, he says, and to “be respectful to all those who are working extremely hard to protect people.”

People should store and handle food safely to avoid food-borne illnesses, and they should also shop for groceries strategically to ensure a balanced menu and avoid creating food waste, Detwiler says. 

“We want to avoid that,” Detwiler says. “You’re having to go out to the store again, and you’re basically making it such that all the people who put so much effort into making sure you’re able to get that fresh produce, pretty much did it for it to be just thrown away.”

Do you have any go-to dos and don’ts for us when it comes to food?

When we look at the idea of why we’re going to the grocery store, we need to think about trying to balance some of our decisions. If we get food that’s all ready to eat—well, ready-to-eat food only lasts so long. If we get food that is all fresh and perishable, that’s great, except you can only eat so many heads of lettuce from the big box store. And you want to make sure that you have a balance of ready-to-eat food, fresh ingredients, and frozen ingredients that can be spaced out over time.

What are your recommendations within those different categories for what people should be grabbing when they go to the grocery store?

It’s just a good blend. When you look at the idea that you want to have fresh produce, you want to have lots of good fruits and vegetables because those are always good in terms of being healthy. Have a balance of them. The frozen foods can and the canned goods can last longer, but look at that kind of fresh produce and how you can use those, so that nothing’s going bad or to waste.

Can you walk us through how to take care of food when we get home?

While there are some new concerns, some very tried and true practice—as I wrote about in my book on food safety, which looked at 25 years of change in food safety culture—still hold true. This idea of cooking, cleaning, separating, and refrigerating. 

Separating: Using different cutting boards, using one for meat, and even using a color-coded cutting board and knife for your salads, your fresh fruits and produce and vegetables, and a different one for your meats. That way you’re not using the same cutting surface, the same utensils, and cross-contamination from raw meat to a salad kind of a scenario. 

Refrigerating: We sometimes take for granted the fact that our refrigerator has to be kept at a temperature. You want to make sure that your refrigerator is at or below 40 degrees Fahrenheit or four degrees Celsius. The freezer should be at zero degrees Fahrenheit or -18 degrees Celsius. The idea of keeping cold foods cold, so that it’s out of the danger zone. This will make it such that it’s going to prevent spoilage, but more importantly, it will prevent foodborne pathogens, like listeria, e. coli, salmonella, from growing rapidly.

Then we move on to cleaning. We want to make sure that our utensils are clean, our areas clean. I’ve dealt with a certain situation recently, where someone realized that they were using a scale a lot more. And they were sick, and I found out through questioning that they were using the scale to measure out their raw chicken. But if you put raw chicken on that surface, you’re now cross-contaminating that surface. 

And finally, cooking. It’s very important that we’re using thermometers, understanding that there are different temperatures, different minimum temperatures to which we should cook leftovers to. 

A couple of other things are very important here. You should thaw frozen meat in the refrigerator or in the microwave, but you’d never want to leave some frozen chicken or beef out on the counter for 24 hours. It’s going to not be cold enough, and it’s not going to be hot enough. It’s going to be in that danger zone, and it’s not going to be safe. So make sure you’re thawing in the refrigerator overnight, marinating foods in the refrigerator. 

Even with shopping, there’s this idea of the two-hour rule. Food should never be out at room temperature, either after you go to the grocery store, or when you take out leftovers after it’s already been cooked—it should never sit out for more than two hours. You need to keep hot foods hot, and you need to keep cold foods cold.

Let’s say we store something in a big dish. How should we go about taking individual portions from that dish for reheating leftovers?

 You’re going to want to heat it up to at least 140 degrees, and having a smaller portion is going to allow you to do that. You don’t want to heat the whole thing of the remaining leftovers just to take a small amount that easily could have been put into a container.

If we’re heating things up multiple times, are we opening the window for that danger zone?

Yes, and I think we need to take this consideration too, because there are some people that will go and buy that  frozen lasagna we’ve been talking about. There’s a lot of people too who are going to go to their favorite local restaurants. Now you do a lot of takeout. The same kind of rules apply. You wouldn’t want to let that sit out for more than two hours. You want to refrigerate those leftovers, and you want to heat up the leftovers.

Other than paying attention to how we thaw meats, is there anything else that we should keep in mind when we’re loading our fridge with a fresh group of groceries?

Do whatever you can to keep your ready-to-eat away from raw food. That’s why containers are very important. You would never want to put some leftover cooked chicken in the same container as raw chicken. 

So think about where and how you’re separating your food, and even that idea of first in, first out. If you have an old head of lettuce from three days ago and for whatever reason you get a new head of lettuce today, because you weren’t communicating with the other person in the household, you want to use the older  head of lettuce before you use the new head of lettuce. 

The same thing can be said for pretty much anything in your refrigerator.

Can you just dive deeper into this idea of storing food and tell us whether all foods should be stored the same way?

There are so many variables there in terms of the packaging. I do know there are some of the more concerning types of foods.

Rice is something that you don’t want to have a lot of leftovers. Try to cook or order enough rice for you to eat that night. You know, dry uncooked rice can last a lot longer, but cooked rice in the refrigerator doesn’t last as long as a lot of people think that it will.

There are a lot of fruits of concern, but one that concerns me the most is cantaloupe. If you’ve got a large number of people in your house staying at home with you, and you can all eat a cantaloupe at once, great. But if it’s just one or two people in the household, and you’re buying a cantaloupe, you cannot properly clean the outside of that. And the longer you have it, once you take the knife through that cantaloupe, you are now opening up the opportunity for any kind of pathogens on the outside that can’t be really cleaned to go into the center of that cantaloupe, which has a pH that kind of supports rapid growth of pathogens. So there are some things like that, where once you cut it up, you want to eat it right away. 

Don’t assume that all meats and all dry goods, beans, and even fruits and vegetables are as safe and shelf stable as others.

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