Unwrapped a New Lunch Box? How to Get Started With Stainless Steel

Congratulations on your new stainless steel lunch box. Whether it came from a thoughtful friend, a family member or yourself, it is the kind of gift that gets used every day for years. The first week is when good habits start, so it is worth a few minutes to learn how it all works.

Stainless steel is simple to use, but it is a little different from the plastic containers most of us grew up with. Here is how to give it a first wash, check the clips, choose the right container for each food, avoid the one big mistake, plan your first week of lunches and store everything so it stays organized.

Start with a first wash

Before you pack food, give everything a good wash in warm, soapy water or run it through the dishwasher. Every ECOlunchbox piece is dishwasher safe. If your set has silicone lids or a removable gasket, wash those too and let every part dry completely before putting it back together.

While you are at it, take a close look at how the pieces fit. Notice which lid goes with which base, how the layers of a bento stack and whether there is a small inner container that nests inside. Knowing the parts now makes packing much faster on a busy morning.

Get to know the clips

Stacking bentos like the Three-in-One Classic use steel side clips to hold the layers together. They are designed to be snug so the box does not pop open in a backpack. The first few times, they may feel a little stiff. Press the clip over the lip of the lid with your thumb, and release it by lifting from the bottom edge.

If a clip feels too loose or too tight after some use, a very gentle adjustment with your fingers usually brings it back. Go slowly and make small changes. Containers with soft-close hinged clips, like the Bento Wet Boxes, should simply be snapped shut and opened, never bent.

Match the container to the food

This is the most important thing to learn. Some stainless containers are leak-proof and some are not. Containers with a silicone lid or gasket, like the Splash Box, Seal Cups and Bento Wet Boxes, are leak-proof and made for soups, yogurt, dressings, cut juicy fruit and saucy leftovers.

All-steel containers with steel lids are not leak-proof. Use them for dry and damp foods like sandwiches, wraps, crackers, cut vegetables, cheese, whole fruit and baked goods. A roomy box like the Solo Rectangle is perfect for a sandwich and sides. If you want a dip with a non-leak-proof bento, nest a small leak-proof Seal Cup Mini inside for hummus or ranch.

What not to do, and your first week of lunches

One rule to remember: never put stainless steel in the microwave. To warm food at work, transfer it to a ceramic or glass bowl first. Pack perishable food chilled with an ice pack in an insulated lunch bag.

For your first week, keep it simple and learn which containers you reach for most:

• Monday: turkey and cheese sandwich, grapes and cucumber slices in an all-steel bento
• Tuesday: pasta salad with a Seal Cup of cherry tomatoes
• Wednesday: hummus, pita, carrots and olives with a leak-proof dip cup
• Thursday: leftover stir-fry and rice in a leak-proof box, to warm in a bowl at work
• Friday: yogurt with granola packed separately and berries

Store it nested and know where to find parts

One of the best things about stainless steel is how little space it takes when it is not in use. Smaller containers nest inside larger ones, so a whole set can live in one drawer or on one shelf. Store lids right alongside their bases, and leave silicone lids resting on top rather than pressed on tightly so everything airs out between uses.

With care, the steel should last a very long time. Silicone lids and gaskets are the parts that eventually wear, and a lost lid happens to everyone. When that day comes, you do not need a new container, just the part. Bookmark the Lids & Parts collection so you know where to find replacements later.

Frequently asked questions

Do I need to wash my new lunch box before using it?

Yes. Give every piece a wash in warm, soapy water or the dishwasher and let it dry completely before packing food.

Which containers can hold soup or yogurt?

Only the ones with a silicone lid or gasket, such as the Seal Cups, Splash Box and Bento Wet Boxes. All-steel lids are for dry and damp foods.

Can I heat food in my stainless steel lunch box?

Not in the microwave. Transfer food to a ceramic or glass bowl to warm it at work.

How do I keep my lunch cold?

Pack food chilled from the fridge and add an ice pack in an insulated lunch bag. Perishable food should not sit at room temperature for more than about two hours.

What if I lose a lid or a gasket wears out?

Replacement lids and parts are available for many containers, so you can keep using the steel base instead of replacing the whole thing.